UNPKG

@mhg/blog

Version:
5 lines 241 kB
<!DOCTYPE html><html lang="zh-Hans"><head hexo-theme="https://github.com/volantis-x/hexo-theme-volantis/#6.0.3"><meta name="generator" content="Hexo 8.1.2"><meta name="Volantis" content="6.0.3"><meta charset="utf-8"><meta name="robots" content="index,follow,max-image-preview:large"><link rel="canonical" href="https://blog.mhuig.top/notes/person/14"><meta http-equiv="x-dns-prefetch-control" content="on"><link rel="dns-prefetch" href="https://static.mhuig.top"><link rel="preconnect" href="https://static.mhuig.top" crossorigin=""><meta name="renderer" content="webkit"><meta name="force-rendering" content="webkit"><meta http-equiv="X-UA-Compatible" content="IE=Edge,chrome=1"><meta name="HandheldFriendly" content="True"><meta name="mobile-web-app-capable" content="yes"><meta name="viewport" content="width=device-width,initial-scale=1,maximum-scale=5"><meta content="black-translucent" name="apple-mobile-web-app-status-bar-style"><meta content="telephone=no" name="format-detection"><script>function registerServiceWorker(e){"localhost"!=window.location.hostname&&"serviceWorker"in navigator&&navigator.serviceWorker.register(`${e}`).then((function(e){"localhost"==window.location.hostname&&(e.onupdatefound=function(){var r=e.installing;r.onstatechange=function(){switch(r.state){case"installed":navigator.serviceWorker.controller?console.log("Updated Service Worker."):console.log("Service Worker Sucess!");break;case"redundant":console.log("The installing service worker became redundant.")}}})})).catch((function(e){console.error("Error during service worker registration:",e),"undefined"==typeof swinstallretry&&(swinstallretry=1,registerServiceWorker("/jquery.js"))}))}registerServiceWorker("/jquery.js")</script><link rel="apple-touch-icon" sizes="180x180" href="/lib/favicon/apple-touch-icon.png"><link rel="icon" type="image/png" sizes="32x32" href="/lib/favicon/favicon-32x32.png"><link rel="icon" type="image/png" sizes="192x192" href="/lib/favicon/android-chrome-192x192.png"><link rel="icon" type="image/png" sizes="144x144" href="/lib/favicon/android-chrome-144x144.png"><link rel="icon" type="image/png" sizes="16x16" href="/lib/favicon/favicon-16x16.png"><link rel="manifest" href="/lib/favicon/site.webmanifest"><link rel="mask-icon" href="/lib/favicon/safari-pinned-tab.svg" color="#5bbad5"><meta name="apple-mobile-web-app-title" content="MHuiG Magicland"><meta name="apple-mobile-web-app-status-bar-style" content="black"><meta name="application-name" content="MHuiG Magicland"><meta name="msapplication-TileColor" content="#87ceeb"><meta name="msapplication-TileImage" content="/lib/favicon/mstile-144x144.png"><meta name="theme-color" content="#87ceeb" media="(prefers-color-scheme: light)"><meta name="theme-color" content="#21232f" media="(prefers-color-scheme: dark)"><link href="/opensearch.xml" rel="search" title="MHuiG Magicland" type="application/opensearchdescription+xml"><link rel="sitemap" type="application/xml" title="MHuiG Blog Site Map" href="https://blog.mhuig.top/sitemap.xml"><link rel="author" href="https://mhuig.top"><meta name="author" content="MHuiG"><meta name="creator" content="MHuiG"><link rel="archives" href="https://blog.mhuig.top/archives/"><link rel="preload" href="/css/style.css" as="style"><link rel="preload" href="https://static.mhuig.top/npm/volantis-static@0.0.1660614606622/media/fonts/VarelaRound/VarelaRound-Regular.ttf" as="font" type="font/ttf" crossorigin="anonymous"><link rel="preload" href="https://static.mhuig.top/npm/volantis-static@0.0.1660614606622/media/fonts/VarelaRound/VarelaRound-Regular.ttf" as="font" type="font/ttf" crossorigin="anonymous"><link rel="alternate" href="/atom.xml" title="Magicland" type="application/atom+xml"><link rel="alternate" href="/rss2.xml" title="Magicland" type="application/rss+xml"><title>History of mathematics: von Neumann约翰·冯·诺依曼在数学与博弈论的多领域奠基性贡献 - Magicland</title><meta name="keywords" content="历史,Person, History,人物,冯·诺伊曼,算子代数,博弈论,遍历理论,MHuiG, @MHuiG, Blog, 博客, Magicland, 魔法世界"><meta desc="" name="description" content="约翰·冯·诺依曼在数学领域贡献卓著,奠定了量子力学的数学基础,并与默里合作建立了冯·诺依曼代数。他在博弈论方面证明了极小极大定理,并与摩根斯坦合著了《博弈论与经济行为》。此外,他还严格证明了遍历定理。 - MHuiG - Magicland"><meta property="og:type" content="website"><meta property="og:title" content="Magicland"><meta property="og:url" content="https://blog.mhuig.top/notes/person/14"><meta property="og:site_name" content="Magicland"><meta property="og:description" content="约翰·冯·诺依曼在数学领域贡献卓著,奠定了量子力学的数学基础,并与默里合作建立了冯·诺依曼代数。他在博弈论方面证明了极小极大定理,并与摩根斯坦合著了《博弈论与经济行为》。此外,他还严格证明了遍历定理。"><meta property="og:locale"><meta property="og:image" content="https://blog.mhuig.top/lib/favicon/android-chrome-192x192.png"><meta property="article:published_time" content="2026-05-10T00:07:00.000Z"><meta property="article:modified_time" content="2026-05-10T00:10:00.000Z"><meta property="article:author" content="MHuiG"><meta property="article:tag" content="History"><meta property="article:tag" content="人物"><meta property="article:tag" content="冯·诺伊曼"><meta property="article:tag" content="博弈论"><meta property="article:tag" content="算子代数"><meta property="article:tag" content="遍历理论"><meta name="twitter:card" content="summary"><meta name="twitter:image" content="https://blog.mhuig.top/lib/favicon/android-chrome-192x192.png"><meta name="twitter:creator" content="@iMHuiG"><meta name="twitter:site" content="@iMHuiG"><style>#safearea{display:none}.post-story+.post-story{content-visibility:auto;contain-intrinsic-size:10px 500px}:root{--color-site-body:#87ceeb;--color-site-bg:#87ceeb;--color-site-inner:#555;--color-site-footer:#666;--color-card:#fff;--color-text:#444;--color-block:#f6f6f6;--color-inlinecode:#d56d28;--color-codeblock:#fff7ea;--color-h1:#3a3a3a;--color-h2:#3a3a3a;--color-h3:#333;--color-h4:#444;--color-h5:#555;--color-h6:#666;--color-p:#444;--color-list:#666;--color-list-hl:#1a78c2;--color-meta:#888;--color-read-bkg:#e0d8c8;--color-read-post:#f8f1e2;--color-copyright-bkg:#f5f5f5}*{box-sizing:border-box;-webkit-box-sizing:border-box;-moz-box-sizing:border-box;outline:0;margin:0;padding:0}::-webkit-scrollbar{height:4px;width:4px}::-webkit-scrollbar-track-piece{background:0 0}::-webkit-scrollbar-thumb{background:#2196f3;cursor:pointer;border-radius:2px;-webkit-border-radius:2px}::-webkit-scrollbar-thumb:hover{background:#ff5722}html{color:var(--color-text);width:100%;height:100%;font-family:"Varela Round","PingFang SC","Microsoft YaHei",Helvetica,Arial,Menlo,Monaco,monospace,sans-serif;font-size:16px}html>::-webkit-scrollbar{height:4px;width:4px}html>::-webkit-scrollbar-track-piece{background:0 0}html>::-webkit-scrollbar-thumb{background:#2196f3;cursor:pointer;border-radius:2px;-webkit-border-radius:2px}html>::-webkit-scrollbar-thumb:hover{background:#ff5722}body{background-color:var(--color-site-body);text-rendering:optimizelegibility;-webkit-tap-highlight-color:transparent;line-height:1.6;-webkit-text-size-adjust:100%;-ms-text-size-adjust:100%}body.modal-active{overflow:hidden}@media screen and (max-width:680px){body.modal-active{position:fixed;top:0;right:0;bottom:0;left:0}}a{color:#2196f3;cursor:pointer;text-decoration:none;transition:all .28s ease;-webkit-transition:all .28s ease;-khtml-transition:all 0.28s ease;-moz-transition:all .28s ease;-o-transition:all .28s ease;-ms-transition:all .28s ease}a:hover{color:#ff5722}a:active,a:hover{outline:0}ol,ul{padding-left:0}ol li,ul li{list-style:none}header{display:-webkit-box;display:-moz-box;display:block}img{border:0;background:0 0;max-width:100%}svg:not(:root){overflow:hidden}hr{-moz-box-sizing:content-box;box-sizing:content-box;-webkit-box-sizing:content-box;-moz-box-sizing:content-box;height:0;border:0;border-radius:1px;-webkit-border-radius:1px;border-bottom:1px solid rgba(68,68,68,.1)}button,input{color:inherit;font:inherit;margin:0}button{overflow:visible;text-transform:none;-webkit-appearance:button;cursor:pointer}@supports (backdrop-filter:blur(20px)){.blur{background:rgba(255,255,255,.9)!important;backdrop-filter:saturate(200%) blur(20px)}}.shadow{box-shadow:0 1px 2px 0 rgba(0,0,0,.1);-webkit-box-shadow:0 1px 2px 0 rgba(0,0,0,.1)}.shadow.floatable{transition:all .28s ease;-webkit-transition:all .28s ease;-khtml-transition:all 0.28s ease;-moz-transition:all .28s ease;-o-transition:all .28s ease;-ms-transition:all .28s ease}.shadow.floatable:hover{box-shadow:0 2px 4px 0 rgba(0,0,0,.1),0 4px 8px 0 rgba(0,0,0,.1),0 8px 16px 0 rgba(0,0,0,.1);-webkit-box-shadow:0 2px 4px 0 rgba(0,0,0,.1),0 4px 8px 0 rgba(0,0,0,.1),0 8px 16px 0 rgba(0,0,0,.1)}#l_cover{min-height:64px}.cover-wrapper{top:0;left:0;max-width:100%;height:100vh;display:-webkit-box;display:-moz-box;display:-ms-flexbox;display:-webkit-flex;display:flex;display:flex;flex-wrap:nowrap;-webkit-flex-wrap:nowrap;-khtml-flex-wrap:nowrap;-moz-flex-wrap:nowrap;-o-flex-wrap:nowrap;-ms-flex-wrap:nowrap;-webkit-box-direction:normal;-moz-box-direction:normal;-webkit-box-orient:vertical;-moz-box-orient:vertical;-webkit-flex-direction:column;-ms-flex-direction:column;flex-direction:column;align-items:center;align-self:center;align-content:center;color:var(--color-site-inner);padding:0 16px;user-select:none;-webkit-user-select:none;-moz-user-select:none;-ms-user-select:none;position:relative;overflow:hidden;margin-bottom:-100px}.cover-wrapper .cover-bg{position:absolute;width:100%;height:100%;background-position:center;background-size:cover;-webkit-background-size:cover;-moz-background-size:cover}.cover-wrapper .cover-bg.lazyload:not(.loaded){opacity:0;-webkit-opacity:0;-moz-opacity:0}.cover-wrapper .cover-bg.lazyload.loaded{animation-delay:0s;animation-duration:.5s;animation-fill-mode:forwards;animation-timing-function:ease-out;animation-name:fadeIn}@-moz-keyframes fadeIn{0%{opacity:0;-webkit-opacity:0;-moz-opacity:0;filter:blur(12px);transform:scale(1.02);-webkit-transform:scale(1.02);-khtml-transform:scale(1.02);-moz-transform:scale(1.02);-o-transform:scale(1.02);-ms-transform:scale(1.02)}100%{opacity:1;-webkit-opacity:1;-moz-opacity:1}}@-webkit-keyframes fadeIn{0%{opacity:0;-webkit-opacity:0;-moz-opacity:0;filter:blur(12px);transform:scale(1.02);-webkit-transform:scale(1.02);-khtml-transform:scale(1.02);-moz-transform:scale(1.02);-o-transform:scale(1.02);-ms-transform:scale(1.02)}100%{opacity:1;-webkit-opacity:1;-moz-opacity:1}}@-o-keyframes fadeIn{0%{opacity:0;-webkit-opacity:0;-moz-opacity:0;filter:blur(12px);transform:scale(1.02);-webkit-transform:scale(1.02);-khtml-transform:scale(1.02);-moz-transform:scale(1.02);-o-transform:scale(1.02);-ms-transform:scale(1.02)}100%{opacity:1;-webkit-opacity:1;-moz-opacity:1}}@keyframes fadeIn{0%{opacity:0;-webkit-opacity:0;-moz-opacity:0;filter:blur(12px);transform:scale(1.02);-webkit-transform:scale(1.02);-khtml-transform:scale(1.02);-moz-transform:scale(1.02);-o-transform:scale(1.02);-ms-transform:scale(1.02)}100%{opacity:1;-webkit-opacity:1;-moz-opacity:1}}.cover-wrapper .cover-body{z-index:1;position:relative;width:100%;height:100%}.cover-wrapper#full{height:calc(100vh + 100px);padding-bottom:100px}.cover-wrapper#half{max-height:640px;min-height:400px;height:calc(36vh - 64px + 200px)}.cover-wrapper #scroll-down{width:100%;height:64px;position:absolute;bottom:100px;text-align:center;cursor:pointer}.cover-wrapper #scroll-down .scroll-down-effects{color:#fff;font-size:24px;line-height:64px;position:absolute;width:24px;left:calc(50% - 12px);text-shadow:0 1px 2px rgba(0,0,0,.1);animation:scroll-down-effect 1.5s infinite;-webkit-animation:scroll-down-effect 1.5s infinite;-khtml-animation:scroll-down-effect 1.5s infinite;-moz-animation:scroll-down-effect 1.5s infinite;-o-animation:scroll-down-effect 1.5s infinite;-ms-animation:scroll-down-effect 1.5s infinite}@-moz-keyframes scroll-down-effect{0%{top:0;opacity:1;-webkit-opacity:1;-moz-opacity:1}50%{top:-16px;opacity:.4;-webkit-opacity:0.4;-moz-opacity:0.4}100%{top:0;opacity:1;-webkit-opacity:1;-moz-opacity:1}}@-webkit-keyframes scroll-down-effect{0%{top:0;opacity:1;-webkit-opacity:1;-moz-opacity:1}50%{top:-16px;opacity:.4;-webkit-opacity:0.4;-moz-opacity:0.4}100%{top:0;opacity:1;-webkit-opacity:1;-moz-opacity:1}}@-o-keyframes scroll-down-effect{0%{top:0;opacity:1;-webkit-opacity:1;-moz-opacity:1}50%{top:-16px;opacity:.4;-webkit-opacity:0.4;-moz-opacity:0.4}100%{top:0;opacity:1;-webkit-opacity:1;-moz-opacity:1}}@keyframes scroll-down-effect{0%{top:0;opacity:1;-webkit-opacity:1;-moz-opacity:1}50%{top:-16px;opacity:.4;-webkit-opacity:0.4;-moz-opacity:0.4}100%{top:0;opacity:1;-webkit-opacity:1;-moz-opacity:1}}.cover-wrapper .cover-body{margin-top:64px;margin-bottom:100px}.cover-wrapper .cover-body,.cover-wrapper .cover-body .bottom,.cover-wrapper .cover-body .top{display:-webkit-box;display:-moz-box;display:-ms-flexbox;display:-webkit-flex;display:flex;display:flex;-webkit-box-direction:normal;-moz-box-direction:normal;-webkit-box-orient:vertical;-moz-box-orient:vertical;-webkit-flex-direction:column;-ms-flex-direction:column;flex-direction:column;align-items:center;justify-content:center;-webkit-justify-content:center;-khtml-justify-content:center;-moz-justify-content:center;-o-justify-content:center;-ms-justify-content:center;max-width:100%}.cover-wrapper .cover-body .bottom{margin-top:32px}.cover-wrapper .cover-body .title{font-family:"Varela Round","PingFang SC","Microsoft YaHei",Helvetica,Arial,Helvetica,monospace;font-size:3.125rem;line-height:1.2;text-shadow:0 1px 2px rgba(0,0,0,.1)}.cover-wrapper .cover-body .subtitle{font-size:20px}.cover-wrapper .cover-body .logo{max-height:120px;max-width:calc(100% - 4 * 16px)}@media screen and (min-height:1024px){.cover-wrapper .cover-body .title{font-size:3rem}.cover-wrapper .cover-body .subtitle{font-size:1.05rem}.cover-wrapper .cover-body .logo{max-height:150px}}.cover-wrapper .cover-body .m_search{position:relative;max-width:calc(100% - 16px);width:320px;vertical-align:middle}.cover-wrapper .cover-body .m_search .form{position:relative;display:-webkit-box;display:-moz-box;display:block;width:100%}.cover-wrapper .cover-body .m_search .icon,.cover-wrapper .cover-body .m_search .input{transition:all .28s ease;-webkit-transition:all .28s ease;-khtml-transition:all 0.28s ease;-moz-transition:all .28s ease;-o-transition:all .28s ease;-ms-transition:all .28s ease}.cover-wrapper .cover-body .m_search .icon{position:absolute;display:-webkit-box;display:-moz-box;display:block;line-height:2.5rem;width:32px;top:0;left:5px;color:rgba(68,68,68,.75)}.cover-wrapper .cover-body .m_search .input{display:-webkit-box;display:-moz-box;display:block;height:2.5rem;width:100%;box-shadow:none;-webkit-box-shadow:none;box-sizing:border-box;-webkit-box-sizing:border-box;-moz-box-sizing:border-box;font-size:.875rem;-webkit-appearance:none;padding-left:36px;border-radius:1.4rem;-webkit-border-radius:1.4rem;background:rgba(255,255,255,.6);backdrop-filter:blur(10px);border:none;color:var(--color-text)}@media screen and (max-width:500px){.cover-wrapper .cover-body .m_search .input{padding-left:36px}}.cover-wrapper .cover-body .m_search .input:hover{background:rgba(255,255,255,.8)}.cover-wrapper .cover-body .m_search .input:focus{background:#fff}.cover-wrapper .list-h{display:-webkit-box;display:-moz-box;display:-ms-flexbox;display:-webkit-flex;display:flex;display:flex;-webkit-box-direction:normal;-moz-box-direction:normal;-webkit-box-orient:horizontal;-moz-box-orient:horizontal;-webkit-flex-direction:row;-ms-flex-direction:row;flex-direction:row;flex-wrap:wrap;-webkit-flex-wrap:wrap;-khtml-flex-wrap:wrap;-moz-flex-wrap:wrap;-o-flex-wrap:wrap;-ms-flex-wrap:wrap;align-items:stretch;border-radius:4px;-webkit-border-radius:4px;user-select:none;-webkit-user-select:none;-moz-user-select:none;-ms-user-select:none}.cover-wrapper .list-h a{-webkit-box-flex:1;-moz-box-flex:1;-webkit-flex:1 0;-ms-flex:1 0;flex:1 0;display:-webkit-box;display:-moz-box;display:-ms-flexbox;display:-webkit-flex;display:flex;display:flex;font-weight:600}.cover-wrapper .list-h a img{display:-webkit-box;display:-moz-box;display:block;border-radius:2px;-webkit-border-radius:2px;margin:4px;min-width:40px;max-width:44px}@media screen and (max-width:768px){.cover-wrapper .list-h a img{min-width:36px;max-width:40px}}@media screen and (max-width:500px){.cover-wrapper .list-h a img{margin:2px 4px;min-width:32px;max-width:36px}}@media screen and (max-width:375px){.cover-wrapper .list-h a img{min-width:28px;max-width:32px}}.cover-wrapper{max-width:100%}.cover-wrapper.search .bottom .menu{margin-top:16px}.cover-wrapper.search .bottom .menu .list-h a{white-space:nowrap;-webkit-box-direction:normal;-moz-box-direction:normal;-webkit-box-orient:horizontal;-moz-box-orient:horizontal;-webkit-flex-direction:row;-ms-flex-direction:row;flex-direction:row;align-items:baseline;padding:2px;margin:4px;color:var(--color-site-inner);opacity:.75;-webkit-opacity:0.75;-moz-opacity:0.75;text-shadow:0 1px 2px rgba(0,0,0,.05);border-bottom:2px solid transparent}.cover-wrapper.search .bottom .menu .list-h a i{margin-right:4px}.cover-wrapper.search .bottom .menu .list-h a p{font-size:.9375rem}.cover-wrapper.search .bottom .menu .list-h a.active,.cover-wrapper.search .bottom .menu .list-h a:active,.cover-wrapper.search .bottom .menu .list-h a:hover{opacity:1;-webkit-opacity:1;-moz-opacity:1;border-bottom:2px solid var(--color-site-inner)}.cover-wrapper.dock .menu,.cover-wrapper.featured .menu,.cover-wrapper.focus .menu{border-radius:6px;-webkit-border-radius:6px}.cover-wrapper.dock .menu .list-h a,.cover-wrapper.featured .menu .list-h a,.cover-wrapper.focus .menu .list-h a{-webkit-box-direction:normal;-moz-box-direction:normal;-webkit-box-orient:vertical;-moz-box-orient:vertical;-webkit-flex-direction:column;-ms-flex-direction:column;flex-direction:column;align-items:center;padding:12px;line-height:24px;border-radius:4px;-webkit-border-radius:4px;border-bottom:none;text-align:center;align-content:flex-end;color:rgba(68,68,68,.7);font-size:1.5rem}@media screen and (max-width:500px){.cover-wrapper.dock .menu .list-h a,.cover-wrapper.featured .menu .list-h a,.cover-wrapper.focus .menu .list-h a{padding:12px 8px}}.cover-wrapper.dock .menu .list-h a i,.cover-wrapper.featured .menu .list-h a i,.cover-wrapper.focus .menu .list-h a i{margin:8px}.cover-wrapper.dock .menu .list-h a p,.cover-wrapper.featured .menu .list-h a p,.cover-wrapper.focus .menu .list-h a p{font-size:.875rem}.cover-wrapper.dock .menu .list-h a.active,.cover-wrapper.featured .menu .list-h a.active,.cover-wrapper.focus .menu .list-h a.active{background:var(--color-card);backdrop-filter:none}.cover-wrapper.dock .menu .list-h a.active i,.cover-wrapper.dock .menu .list-h a.active i+p,.cover-wrapper.featured .menu .list-h a.active i,.cover-wrapper.featured .menu .list-h a.active i+p,.cover-wrapper.focus .menu .list-h a.active i,.cover-wrapper.focus .menu .list-h a.active i+p{color:#2196f3}.cover-wrapper.dock .menu .list-h a.active img+p,.cover-wrapper.featured .menu .list-h a.active img+p,.cover-wrapper.focus .menu .list-h a.active img+p{color:var(--color-text)}.cover-wrapper.dock .menu .list-h a:hover,.cover-wrapper.featured .menu .list-h a:hover,.cover-wrapper.focus .menu .list-h a:hover{background:var(--color-card)}.cover-wrapper.featured .menu .list-h{margin:-2px}.cover-wrapper.featured .menu .list-h a{margin:2px;background:rgba(255,255,255,.5)}@supports (backdrop-filter:blur(20px)){.cover-wrapper.featured .menu .list-h a{background:rgba(255,255,255,.5);backdrop-filter:saturate(200%) blur(20px)}}@media (prefers-color-scheme:dark){:root{--color-mode:'dark'}:root:not([color-scheme]){--color-site-body:#121212;--color-read-bkg:#21232f;--color-read-post:#252d38;--color-site-bg:#21232f;--color-site-inner:#efefef;--color-site-footer:#666;--color-card:#252d38;--color-text:rgba(238,238,238,0.871);--color-block:rgba(68,68,68,0.65);--color-codeblock:#444;--color-inlinecode:#d56d28;--color-h1:rgba(255,255,255,0.871);--color-h2:rgba(255,255,255,0.871);--color-h3:rgba(255,255,255,0.6);--color-h4:rgba(255,255,255,0.6);--color-h5:rgba(255,255,255,0.6);--color-h6:rgba(255,255,255,0.6);--color-p:rgba(217,217,217,0.871);--color-list:rgba(217,217,217,0.871);--color-list-hl:#4dabf5;--color-meta:rgba(191,191,191,0.871);--color-link:rgba(191,191,191,0.871);--color-copyright-bkg:#21252b}:root:not([color-scheme]) img{filter:brightness(70%)!important}:root:not([color-scheme]) .blur{background:rgba(33,35,47,.9)!important}:root:not([color-scheme]) .white-box.blur{background:rgba(37,45,56,.9)!important}:root:not([color-scheme]) .nav-main .u-search-input{background:var(--color-card)!important}:root:not([color-scheme]) #l_main .article .prev-next>a{background:var(--color-block)!important}:root:not([color-scheme]) #l_main .article .prev-next>a:hover{background:var(--color-site-bg)!important}:root:not([color-scheme]) .article blockquote{background:var(--color-block)!important}:root:not([color-scheme]) .article-title a{color:var(--color-h1)!important}:root:not([color-scheme]) details>summary{color:var(--color-p)!important;background:var(--color-site-bg)!important}:root:not([color-scheme]) details{border:1px solid var(--color-site-bg)!important;background:var(--color-site-bg)!important}:root:not([color-scheme]) #u-search .modal,:root:not([color-scheme]) #u-search .modal-body,:root:not([color-scheme]) #u-search .modal-header{background:var(--color-card)!important}:root:not([color-scheme]) #u-search .modal-body .modal-results .result:hover{background:var(--color-block)!important}:root:not([color-scheme]) .u-search-input:hover{background:var(--color-block)!important}:root:not([color-scheme]) .u-search-input:focus{background:var(--color-site-body)!important}}[color-scheme=dark]{--color-site-body:#121212;--color-read-bkg:#21232f;--color-read-post:#252d38;--color-site-bg:#21232f;--color-site-inner:#efefef;--color-site-footer:#666;--color-card:#252d38;--color-text:rgba(238,238,238,0.871);--color-block:rgba(68,68,68,0.65);--color-codeblock:#444;--color-inlinecode:#d56d28;--color-h1:rgba(255,255,255,0.871);--color-h2:rgba(255,255,255,0.871);--color-h3:rgba(255,255,255,0.6);--color-h4:rgba(255,255,255,0.6);--color-h5:rgba(255,255,255,0.6);--color-h6:rgba(255,255,255,0.6);--color-p:rgba(217,217,217,0.871);--color-list:rgba(217,217,217,0.871);--color-list-hl:#4dabf5;--color-meta:rgba(191,191,191,0.871);--color-link:rgba(191,191,191,0.871);--color-copyright-bkg:#21252b}[color-scheme=dark] img{filter:brightness(70%)!important}[color-scheme=dark] .blur{background:rgba(33,35,47,.9)!important}[color-scheme=dark] .white-box.blur{background:rgba(37,45,56,.9)!important}[color-scheme=dark] .nav-main .u-search-input{background:var(--color-card)!important}[color-scheme=dark] #l_main .article .prev-next>a{background:var(--color-block)!important}[color-scheme=dark] #l_main .article .prev-next>a:hover{background:var(--color-site-bg)!important}[color-scheme=dark] .article blockquote{background:var(--color-block)!important}[color-scheme=dark] .article-title a{color:var(--color-h1)!important}[color-scheme=dark] details>summary{color:var(--color-p)!important;background:var(--color-site-bg)!important}[color-scheme=dark] details{border:1px solid var(--color-site-bg)!important;background:var(--color-site-bg)!important}[color-scheme=dark] #u-search .modal,[color-scheme=dark] #u-search .modal-body,[color-scheme=dark] #u-search .modal-header{background:var(--color-card)!important}[color-scheme=dark] #u-search .modal-body .modal-results .result:hover{background:var(--color-block)!important}[color-scheme=dark] .u-search-input:hover{background:var(--color-block)!important}[color-scheme=dark] .u-search-input:focus{background:var(--color-site-body)!important}@media screen and (max-width:500px){[color-scheme=dark] .l_header .m_search{background:var(--color-site-bg)!important}}@font-face{font-family:'Varela Round';src:url("https://static.mhuig.top/npm/volantis-static@0.0.1660614606622/media/fonts/VarelaRound/VarelaRound-Regular.ttf");font-weight:'normal';font-style:'normal';font-display:swap}@font-face{font-family:'Varela Round';src:url("https://static.mhuig.top/npm/volantis-static@0.0.1660614606622/media/fonts/VarelaRound/VarelaRound-Regular.ttf");font-weight:'normal';font-style:'normal';font-display:swap}.l_header{position:fixed;z-index:1000;top:0;width:100%;height:64px;background:var(--color-card);box-shadow:0 1px 2px 0 rgba(0,0,0,.1);-webkit-box-shadow:0 1px 2px 0 rgba(0,0,0,.1)}.l_header.auto{transition:opacity .4s ease;-webkit-transition:opacity .4s ease;-khtml-transition:opacity 0.4s ease;-moz-transition:opacity .4s ease;-o-transition:opacity .4s ease;-ms-transition:opacity .4s ease;visibility:hidden}.l_header.auto.show{opacity:1!important;-webkit-opacity:1!important;-moz-opacity:1!important;visibility:visible}.l_header .container{margin-left:16px;margin-right:16px}.l_header #wrapper{height:100%;user-select:none;-webkit-user-select:none;-moz-user-select:none;-ms-user-select:none}.l_header #wrapper .nav-main,.l_header #wrapper .nav-sub{display:-webkit-box;display:-moz-box;display:-ms-flexbox;display:-webkit-flex;display:flex;display:flex;flex-wrap:nowrap;-webkit-flex-wrap:nowrap;-khtml-flex-wrap:nowrap;-moz-flex-wrap:nowrap;-o-flex-wrap:nowrap;-ms-flex-wrap:nowrap;justify-content:space-between;-webkit-justify-content:space-between;-khtml-justify-content:space-between;-moz-justify-content:space-between;-o-justify-content:space-between;-ms-justify-content:space-between;align-items:center}.l_header #wrapper .nav-main{transition:all .28s ease;-webkit-transition:all .28s ease;-khtml-transition:all 0.28s ease;-moz-transition:all .28s ease;-o-transition:all .28s ease;-ms-transition:all .28s ease}.l_header #wrapper.sub .nav-main{transform:translateY(-64px);-webkit-transform:translateY(-64px);-khtml-transform:translateY(-64px);-moz-transform:translateY(-64px);-o-transform:translateY(-64px);-ms-transform:translateY(-64px)}.l_header #wrapper .nav-sub{transition:all .28s ease;-webkit-transition:all .28s ease;-khtml-transition:all 0.28s ease;-moz-transition:all .28s ease;-o-transition:all .28s ease;-ms-transition:all .28s ease;opacity:0;-webkit-opacity:0;-moz-opacity:0;height:64px;width:calc(100% - 2 * 16px);position:absolute}.l_header #wrapper .nav-sub ::-webkit-scrollbar{display:-webkit-box;display:-moz-box;display:none}@media screen and (min-width:2048px){.l_header #wrapper .nav-sub{max-width:55vw;margin:auto}}.l_header #wrapper.sub .nav-sub{opacity:1;-webkit-opacity:1;-moz-opacity:1}.l_header #wrapper .title{position:relative;color:var(--color-text);padding-left:24px;max-height:64px}.l_header #wrapper .nav-main .title{white-space:nowrap;overflow:hidden;text-overflow:ellipsis;flex-shrink:0;line-height:64px;padding:0 24px;font-size:1.25rem;font-family:"Varela Round","PingFang SC","Microsoft YaHei",Helvetica,Arial,Helvetica,monospace}.l_header #wrapper .nav-main .title img{height:64px}.l_header .nav-sub{max-width:1080px;margin:auto}.l_header .nav-sub .title{font-weight:700;font-family:"Varela Round","PingFang SC","Microsoft YaHei",Helvetica,Arial,Menlo,Monaco,monospace,sans-serif;line-height:1.2;max-height:64px;white-space:normal;flex-shrink:1}.l_header .switcher{display:-webkit-box;display:-moz-box;display:none;line-height:64px;align-items:center}.l_header .switcher .s-toc{display:-webkit-box;display:-moz-box;display:none}@media screen and (max-width:768px){.l_header .switcher .s-toc{display:-webkit-box;display:-moz-box;display:-ms-flexbox;display:-webkit-flex;display:flex;display:flex}}.l_header .switcher>li{height:48px;transition:all .28s ease;-webkit-transition:all .28s ease;-khtml-transition:all 0.28s ease;-moz-transition:all .28s ease;-o-transition:all .28s ease;-ms-transition:all .28s ease;margin:2px}@media screen and (max-width:500px){.l_header .switcher>li{margin:0 1px;height:48px}}.l_header .switcher>li>a{display:-webkit-box;display:-moz-box;display:-ms-flexbox;display:-webkit-flex;display:flex;display:flex;justify-content:center;-webkit-justify-content:center;-khtml-justify-content:center;-moz-justify-content:center;-o-justify-content:center;-ms-justify-content:center;align-items:center;width:48px;height:48px;padding:.85em 1.1em;border-radius:100px;-webkit-border-radius:100px;border:none;transition:all .28s ease;-webkit-transition:all .28s ease;-khtml-transition:all 0.28s ease;-moz-transition:all .28s ease;-o-transition:all .28s ease;-ms-transition:all .28s ease;color:#2196f3}.l_header .switcher>li>a:hover{border:none}.l_header .switcher>li>a.active,.l_header .switcher>li>a:active{border:none;background:var(--color-site-bg)}@media screen and (max-width:500px){.l_header .switcher>li>a{width:36px;height:48px}}.l_header .nav-sub .switcher{display:-webkit-box;display:-moz-box;display:-ms-flexbox;display:-webkit-flex;display:flex;display:flex}.l_header .m_search{display:-webkit-box;display:-moz-box;display:-ms-flexbox;display:-webkit-flex;display:flex;display:flex;height:64px;width:240px;transition:all .28s ease;-webkit-transition:all .28s ease;-khtml-transition:all 0.28s ease;-moz-transition:all .28s ease;-o-transition:all .28s ease;-ms-transition:all .28s ease}@media screen and (max-width:1024px){.l_header .m_search{width:44px;min-width:44px}.l_header .m_search input::placeholder{opacity:0;-webkit-opacity:0;-moz-opacity:0}.l_header .m_search:hover{width:240px}.l_header .m_search:hover input::placeholder{opacity:1;-webkit-opacity:1;-moz-opacity:1}}@media screen and (min-width:500px){.l_header .m_search:hover .input{width:100%}.l_header .m_search:hover .input::placeholder{opacity:1;-webkit-opacity:1;-moz-opacity:1}}@media screen and (max-width:500px){.l_header .m_search{min-width:0}.l_header .m_search input::placeholder{opacity:1;-webkit-opacity:1;-moz-opacity:1}}.l_header .m_search .form{position:relative;display:-webkit-box;display:-moz-box;display:-ms-flexbox;display:-webkit-flex;display:flex;display:flex;width:100%;align-items:center}.l_header .m_search .icon{position:absolute;width:36px;left:5px;color:var(--color-meta)}@media screen and (max-width:500px){.l_header .m_search .icon{display:-webkit-box;display:-moz-box;display:none}}.l_header .m_search .input{display:-webkit-box;display:-moz-box;display:block;padding-top:8px;padding-bottom:8px;line-height:1.3;width:100%;color:var(--color-text);background:#fafafa;box-shadow:none;-webkit-box-shadow:none;box-sizing:border-box;-webkit-box-sizing:border-box;-moz-box-sizing:border-box;padding-left:40px;font-size:.875rem;border-radius:8px;-webkit-border-radius:8px;border:none;transition:all .28s ease;-webkit-transition:all .28s ease;-khtml-transition:all 0.28s ease;-moz-transition:all .28s ease;-o-transition:all .28s ease;-ms-transition:all .28s ease}@media screen and (min-width:500px){.l_header .m_search .input:focus{box-shadow:0 4px 8px 0 rgba(0,0,0,.1);-webkit-box-shadow:0 4px 8px 0 rgba(0,0,0,.1)}}@media screen and (max-width:500px){.l_header .m_search .input{background:var(--color-block);padding-left:8px;border:none}.l_header .m_search .input:focus,.l_header .m_search .input:hover{border:none}}@media (max-width:500px){.l_header .m_search{left:0;width:0;overflow:hidden;position:absolute;background:#fff;transition:all .28s ease;-webkit-transition:all .28s ease;-khtml-transition:all 0.28s ease;-moz-transition:all .28s ease;-o-transition:all .28s ease;-ms-transition:all .28s ease}.l_header .m_search .input{border-radius:32px;-webkit-border-radius:32px;margin-left:16px;padding-left:16px}.l_header.z_search-open .m_search{width:100%}.l_header.z_search-open .m_search .input{width:calc(100% - 120px)}}ul.m-pc>li>a{color:inherit;border-bottom:2px solid transparent}ul.m-pc>li>a.active,ul.m-pc>li>a:active{border-bottom:2px solid #2196f3}ul.list-v li:hover>ul.list-v,ul.m-pc li:hover>ul.list-v{display:-webkit-box;display:-moz-box;display:block}ul.nav-list-h{display:-webkit-box;display:-moz-box;display:-ms-flexbox;display:-webkit-flex;display:flex;display:flex;align-items:stretch}ul.nav-list-h>li{position:relative;justify-content:center;-webkit-justify-content:center;-khtml-justify-content:center;-moz-justify-content:center;-o-justify-content:center;-ms-justify-content:center;height:100%;line-height:2.4;border-radius:4px;-webkit-border-radius:4px}ul.nav-list-h>li>a{-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;font-weight:600}ul.list-v{z-index:1;display:-webkit-box;display:-moz-box;display:none;position:absolute;background:var(--color-card);box-shadow:0 2px 4px 0 rgba(0,0,0,.08),0 4px 8px 0 rgba(0,0,0,.08),0 8px 16px 0 rgba(0,0,0,.08);-webkit-box-shadow:0 2px 4px 0 rgba(0,0,0,.08),0 4px 8px 0 rgba(0,0,0,.08),0 8px 16px 0 rgba(0,0,0,.08);margin-top:-6px;border-radius:4px;-webkit-border-radius:4px;padding:8px 0}ul.list-v.show{display:-webkit-box;display:-moz-box;display:block}ul.list-v hr{margin-top:8px;margin-bottom:8px}ul.list-v>li{white-space:nowrap;word-break:keep-all}ul.list-v>li.header{font-size:.78125rem;font-weight:700;line-height:2em;color:var(--color-meta);margin:8px 16px 4px}ul.list-v>li.header i{margin-right:8px}ul.list-v>li ul{margin-left:0;display:-webkit-box;display:-moz-box;display:none;margin-top:-40px}ul.list-v .aplayer-container{min-height:64px;padding:6px 16px}ul.list-v>li>a{transition:all .28s ease;-webkit-transition:all .28s ease;-khtml-transition:all 0.28s ease;-moz-transition:all .28s ease;-o-transition:all .28s ease;-ms-transition:all .28s ease;display:-webkit-box;display:-moz-box;display:block;color:var(--color-list);font-size:.875rem;font-weight:700;line-height:36px;padding:0 20px 0 16px;text-overflow:ellipsis;margin:0 4px;border-radius:4px;-webkit-border-radius:4px}@media screen and (max-width:1024px){ul.list-v>li>a{line-height:40px}}ul.list-v>li>a>i{margin-right:8px}ul.list-v>li>a.active,ul.list-v>li>a:active{color:var(--color-list-hl)}ul.list-v>li>a:hover{color:var(--color-list-hl);background:var(--color-site-bg)}.l_header .menu>ul>li>a{display:-webkit-box;display:-moz-box;display:block;padding:0 8px}.l_header .menu>ul>li>a>i{margin-right:4px}.l_header ul.nav-list-h>li{color:var(--color-list);line-height:64px}.l_header ul.nav-list-h>li>a{max-height:64px;overflow:hidden;color:inherit}.l_header ul.nav-list-h>li>a.active,.l_header ul.nav-list-h>li>a:active{color:#2196f3}.l_header ul.nav-list-h>li:hover>a{color:var(--color-list-hl)}.l_header ul.nav-list-h>li i.music{animation:rotate-effect 1.5s linear infinite;-webkit-animation:rotate-effect 1.5s linear infinite;-khtml-animation:rotate-effect 1.5s linear infinite;-moz-animation:rotate-effect 1.5s linear infinite;-o-animation:rotate-effect 1.5s linear infinite;-ms-animation:rotate-effect 1.5s linear infinite}@-moz-keyframes rotate-effect{0%{transform:rotate(0);-webkit-transform:rotate(0);-khtml-transform:rotate(0);-moz-transform:rotate(0);-o-transform:rotate(0);-ms-transform:rotate(0)}25%{transform:rotate(90deg);-webkit-transform:rotate(90deg);-khtml-transform:rotate(90deg);-moz-transform:rotate(90deg);-o-transform:rotate(90deg);-ms-transform:rotate(90deg)}50%{transform:rotate(180deg);-webkit-transform:rotate(180deg);-khtml-transform:rotate(180deg);-moz-transform:rotate(180deg);-o-transform:rotate(180deg);-ms-transform:rotate(180deg)}75%{transform:rotate(270deg);-webkit-transform:rotate(270deg);-khtml-transform:rotate(270deg);-moz-transform:rotate(270deg);-o-transform:rotate(270deg);-ms-transform:rotate(270deg)}100%{transform:rotate(360deg);-webkit-transform:rotate(360deg);-khtml-transform:rotate(360deg);-moz-transform:rotate(360deg);-o-transform:rotate(360deg);-ms-transform:rotate(360deg)}}@-webkit-keyframes rotate-effect{0%{transform:rotate(0);-webkit-transform:rotate(0);-khtml-transform:rotate(0);-moz-transform:rotate(0);-o-transform:rotate(0);-ms-transform:rotate(0)}25%{transform:rotate(90deg);-webkit-transform:rotate(90deg);-khtml-transform:rotate(90deg);-moz-transform:rotate(90deg);-o-transform:rotate(90deg);-ms-transform:rotate(90deg)}50%{transform:rotate(180deg);-webkit-transform:rotate(180deg);-khtml-transform:rotate(180deg);-moz-transform:rotate(180deg);-o-transform:rotate(180deg);-ms-transform:rotate(180deg)}75%{transform:rotate(270deg);-webkit-transform:rotate(270deg);-khtml-transform:rotate(270deg);-moz-transform:rotate(270deg);-o-transform:rotate(270deg);-ms-transform:rotate(270deg)}100%{transform:rotate(360deg);-webkit-transform:rotate(360deg);-khtml-transform:rotate(360deg);-moz-transform:rotate(360deg);-o-transform:rotate(360deg);-ms-transform:rotate(360deg)}}@-o-keyframes rotate-effect{0%{transform:rotate(0);-webkit-transform:rotate(0);-khtml-transform:rotate(0);-moz-transform:rotate(0);-o-transform:rotate(0);-ms-transform:rotate(0)}25%{transform:rotate(90deg);-webkit-transform:rotate(90deg);-khtml-transform:rotate(90deg);-moz-transform:rotate(90deg);-o-transform:rotate(90deg);-ms-transform:rotate(90deg)}50%{transform:rotate(180deg);-webkit-transform:rotate(180deg);-khtml-transform:rotate(180deg);-moz-transform:rotate(180deg);-o-transform:rotate(180deg);-ms-transform:rotate(180deg)}75%{transform:rotate(270deg);-webkit-transform:rotate(270deg);-khtml-transform:rotate(270deg);-moz-transform:rotate(270deg);-o-transform:rotate(270deg);-ms-transform:rotate(270deg)}100%{transform:rotate(360deg);-webkit-transform:rotate(360deg);-khtml-transform:rotate(360deg);-moz-transform:rotate(360deg);-o-transform:rotate(360deg);-ms-transform:rotate(360deg)}}@keyframes rotate-effect{0%{transform:rotate(0);-webkit-transform:rotate(0);-khtml-transform:rotate(0);-moz-transform:rotate(0);-o-transform:rotate(0);-ms-transform:rotate(0)}25%{transform:rotate(90deg);-webkit-transform:rotate(90deg);-khtml-transform:rotate(90deg);-moz-transform:rotate(90deg);-o-transform:rotate(90deg);-ms-transform:rotate(90deg)}50%{transform:rotate(180deg);-webkit-transform:rotate(180deg);-khtml-transform:rotate(180deg);-moz-transform:rotate(180deg);-o-transform:rotate(180deg);-ms-transform:rotate(180deg)}75%{transform:rotate(270deg);-webkit-transform:rotate(270deg);-khtml-transform:rotate(270deg);-moz-transform:rotate(270deg);-o-transform:rotate(270deg);-ms-transform:rotate(270deg)}100%{transform:rotate(360deg);-webkit-transform:rotate(360deg);-khtml-transform:rotate(360deg);-moz-transform:rotate(360deg);-o-transform:rotate(360deg);-ms-transform:rotate(360deg)}}.menu-phone li ul.list-v{right:calc(100% - .5 * 16px)}.menu-phone li ul.list-v ul{right:calc(100% - .5 * 16px)}#wrapper{max-width:1080px;margin:auto}@media screen and (min-width:2048px){#wrapper{max-width:55vw}}#wrapper .menu{-webkit-box-flex:1;-moz-box-flex:1;-webkit-flex:1 1;-ms-flex:1 1;flex:1 1;margin:0 16px 0 0}#wrapper .menu .list-v ul{left:calc(100% - .5 * 16px)}.menu-phone{display:-webkit-box;display:-moz-box;display:none;margin-top:16px;right:8px;transition:all .28s ease;-webkit-transition:all .28s ease;-khtml-transition:all 0.28s ease;-moz-transition:all .28s ease;-o-transition:all .28s ease;-ms-transition:all .28s ease}.menu-phone ul{right:calc(100% - .5 * 16px)}@media screen and (max-width:500px){.menu-phone{display:-webkit-box;display:-moz-box;display:block}}.l_header{max-width:65vw;left:calc((100% - 65vw) * .5);border-bottom-left-radius:8px;border-bottom-right-radius:8px}@media screen and (max-width:2048px){.l_header{max-width:1112px;left:calc((100% - 1112px) * .5)}}@media screen and (max-width:1112px){.l_header{left:0;border-radius:0;-webkit-border-radius:0;max-width:100%}}@media screen and (max-width:500px){.l_header .container{margin-left:0;margin-right:0}.l_header #wrapper .nav-main .title{padding-left:16px;padding-right:16px}.l_header #wrapper .nav-sub{width:100%}.l_header #wrapper .nav-sub .title{overflow-y:scroll;margin-top:2px;padding:8px 16px}.l_header #wrapper .switcher{display:-webkit-box;display:-moz-box;display:-ms-flexbox;display:-webkit-flex;display:flex;display:flex;margin-right:8px}.l_header .menu{display:-webkit-box;display:-moz-box;display:none}}@media screen and (max-width:500px){.list-v li{max-width:270px}}#u-search{display:-webkit-box;display:-moz-box;display:none;position:fixed;top:0;left:0;width:100%;height:100%;padding:60px 20px;z-index:1001}@media screen and (max-width:680px){#u-search{padding:0}}@media screen and (prefers-color-scheme:dark) and (max-width:500px){.l_header .m_search{background:var(--color-site-bg)!important}}.cover-wrapper .cover-body .subtitle{font-size:.875rem}.fa-brands.color-github,.fa-duotone.color-github,.fa-light.color-github,.fa-regular.color-github,.fa-solid.color-github,.fa-thin.color-github,.fa.color-github,.fad.color-github,.fal.color-github,.far.color-github,.fas.color-github,.iziToast>.iziToast-body .iziToast-icon.color-github{color:#000}.fa-brands.color-friends,.fa-duotone.color-friends,.fa-light.color-friends,.fa-regular.color-friends,.fa-solid.color-friends,.fa-thin.color-friends,.fa.color-friends,.fad.color-friends,.fal.color-friends,.far.color-friends,.fas.color-friends,.iziToast>.iziToast-body .iziToast-icon.color-friends{color:#d31ee9}.fa-brands.color-about,.fa-duotone.color-about,.fa-light.color-about,.fa-regular.color-about,.fa-solid.color-about,.fa-thin.color-about,.fa.color-about,.fad.color-about,.fal.color-about,.far.color-about,.fas.color-about,.iziToast>.iziToast-body .iziToast-icon.color-about{color:#0095ff}.fa-brands.color-travellings,.fa-duotone.color-travellings,.fa-light.color-travellings,.fa-regular.color-travellings,.fa-solid.color-travellings,.fa-thin.color-travellings,.fa.color-travellings,.fad.color-travellings,.fal.color-travellings,.far.color-travellings,.fas.color-travellings,.iziToast>.iziToast-body .iziToast-icon.color-travellings{color:#734ae6}mjx-container{padding:0 0!important}mjx-container:not([display=true]){padding:4px 2px 4px 6px!important}mjx-container[jax=SVG]{direction:ltr}mjx-container[jax=SVG]>svg{overflow:visible}mjx-container[jax=SVG][display=true]{display:-webkit-box;display:-moz-box;display:block;text-align:center;margin:1em 0}mjx-container[jax=SVG][justify=left]{text-align:left}mjx-container[jax=SVG][justify=right]{text-align:right}g[data-mml-node=merror]>g{fill:#f00;stroke:#f00}g[data-mml-node=merror]>rect[data-background]{fill:#ff0;stroke:none}g[data-mml-node=mtable]>line[data-line]{stroke-width:70px;fill:none}g[data-mml-node=mtable]>rect[data-frame]{stroke-width:70px;fill:none}g[data-mml-node=mtable]>.mjx-dashed{stroke-dasharray:140}g[data-mml-node=mtable]>.mjx-dotted{stroke-linecap:round;stroke-dasharray:0,140}g[data-mml-node=mtable]>svg{overflow:visible}[jax=SVG] mjx-tool{display:-webkit-box;display:-moz-box;display:inline-block;position:relative;width:0;height:0}[jax=SVG] mjx-tool>mjx-tip{position:absolute;top:0;left:0}mjx-tool>mjx-tip{display:-webkit-box;display:-moz-box;display:inline-block;padding:.2em;border:1px solid #888;font-size:70%;background-color:#f8f8f8;color:#000;box-shadow:2px 2px 5px #aaa;-webkit-box-shadow:2px 2px 5px #aaa}g[data-mml-node=maction][data-toggle]{cursor:pointer}mjx-status{display:-webkit-box;display:-moz-box;display:block;position:fixed;left:1em;bottom:1em;min-width:25%;padding:.2em .4em;border:1px solid #888;font-size:90%;background-color:#f8f8f8;color:#000}foreignObject[data-mjx-xml]{font-family:initial;line-height:normal;overflow:visible}.MathJax path{stroke-width:3}mjx-container[display=true]{overflow:auto hidden}mjx-container[display=true]+br{display:-webkit-box;display:-moz-box;display:none}</style><link rel="stylesheet" href="/css/style.css" media="print" onload='this.media="all",this.onload=null'><noscript><link rel="stylesheet" href="/css/style.css"></noscript><script>let userColorScheme=localStorage.getItem("color-scheme");userColorScheme&&document.documentElement.setAttribute("color-scheme",userColorScheme)</script><script>window.MSInputMethodContext&&document.documentMode&&document.write('<style>html{overflow-x: hidden !important;overflow-y: hidden !important;}.kill-ie{text-align:center;height: 100%;margin-top: 15%;margin-bottom: 5500%;}.kill-t{font-size: 2rem;}.kill-c{font-size: 1.2rem;}#l_header,#l_body{display: none;}</style><div class="kill-ie"><span class="kill-t"><b>抱歉,您的浏览器无法访问本站</b></span><br/><span class="kill-c">微软已经于2016年终止了对 Internet Explorer (IE) 10 及更早版本的支持,<br/>继续使用存在极大的安全隐患,请使用当代主流的浏览器进行访问。</span><br/><a target="_blank" rel="noopener" href="https://blogs.windows.com/windowsexperience/2021/05/19/the-future-of-internet-explorer-on-windows-10-is-in-microsoft-edge/"><strong>了解详情 ></strong></a></div>')</script><noscript><style>html{overflow-x:hidden!important;overflow-y:hidden!important}.kill-noscript{text-align:center;height:100%;margin-top:15%;margin-bottom:5500%}.kill-t{font-size:2rem}.kill-c{font-size:1.2rem}#l_body,#l_header{display:none}</style><div class="kill-noscript"> <span class="kill-t"><b>抱歉,您的浏览器无法访问本站</b></span><br> <span class="kill-c">本页面需要浏览器支持(启用)JavaScript</span><br> <a target="_blank" rel="external nofollow noopener noreferrer" href="https://www.baidu.com/s?wd=启用JavaScript"><strong>了解详情 ></strong></a></div></noscript><script>function volantisEventListener(e,t,n){this.type=e,this.f=t,this.ele=n}function volantisDom(e){return e||(e=document.createElement("div")),this.ele=e,this.ele.find=e=>{let t=this.ele.querySelector(e);if(t)return new volantisDom(t)},this.ele.hasClass=e=>this.ele.className.match(new RegExp("(\\s|^)"+e+"(\\s|$)")),this.ele.addClass=e=>(this.ele.classList.add(e),this.ele),this.ele.removeClass=e=>(this.ele.classList.remove(e),this.ele),this.ele.toggleClass=e=>(this.ele.hasClass(e)?this.ele.removeClass(e):this.ele.addClass(e),this.ele),this.ele.on=(e,t,n=1)=>(this.ele.addEventListener(e,t,!1),n&&volantis.EventListener.list.push(new volantisEventListener(e,t,this.ele)),this.ele),this.ele.click=(e,t)=>(this.ele.on("click",e,t),this.ele),this.ele.scroll=(e,t)=>(this.ele.on("scroll",e,t),this.ele),this.ele.html=e=>(this.ele.innerHTML=e,this.ele),this.ele.hide=e=>(this.ele.style.display="none",this.ele),this.ele.show=e=>(this.ele.style.display="block",this.ele),this.ele}function RunItem(){function e(e,t){this.name=t||volantis.getFunctionHash(e),this.run=()=>{try{e()}catch(e){console.log(e)}}}this.list=[],this.start=()=>{for(var e=0;e<this.list.length;e++)this.list[e].run()},this.push=(t,n,o=!0)=>{if("function"!=typeof t)return;let l=t;o&&(l=()=>{volantis.requestAnimationFrame(t)}),n=n||volantis.getFunctionHash(t);const i=this.list.findIndex((e=>e.name===n));-1===i?this.list.push(new e(l,n)):this.list[i]=new e(l,n)},this.remove=e=>{for(let t=0;t<this.list.length;t++){this.list[t].name==e&&this.list.splice(t,1)}}}function errorImgAvatar(e){e.src="https://static.mhuig.top/npm/volantis-static@0.0.1660614606622/media/placeholder/avatar/round/3442075.svg",e.onerror=null}function errorImgCover(e){e.src="https://static.mhuig.top/npm/volantis-static@0.0.1660614606622/media/placeholder/cover/76b86c0226ffd.svg",e.onerror=null}!function(){const e=new WeakMap,t=new Proxy({},{get(n,o){const l=e.get(t);return l?.[o]},set(n,o,l){e.has(t)||e.set(t,Object.create(null));return e.get(t)[o]=l,!0},deleteProperty(n,o){const l=e.get(t);return!(!l||!Object.prototype.hasOwnProperty.call(l,o))&&(delete l[o],0===Object.keys(l).length&&e.delete(t),!0)},ownKeys(n){const o=e.get(t);return o?Object.keys(o):[]},getOwnPropertyDescriptor(n,o){const l=e.get(t);if(l&&Object.prototype.hasOwnProperty.call(l,o))return{value:l[o],writable:!0,enumerable:!0,configurable:!0}}});Object.defineProperty(window,"volantis",{value:t,writable:!0,configurable:!0,enumerable:!0})}(),volantis.debug="false",volantis.dom={},volantis.simpleTextHash=e=>{let t=5381;for(let n=0;n<e.length;n++)t=(t<<5)+t+e.charCodeAt(n),t&=t;return t.toString(16).padStart(8,"0")},volantis.getFunctionHash=e=>{const t=e.toString();return volantis.simpleTextHash(t)},volantis.EventListener={},volantis.EventListener.list=[],volantis.EventListener.remove=()=>{volantis.EventListener.list.forEach((function(e){e.ele.removeEventListener(e.type,e.f,!1)})),volantis.EventListener.list=[]},volantis.dom.$=e=>e?new volantisDom(e):null,volantis.pjax={},volantis.pjax.method={complete:new RunItem,error:new RunItem,send:new RunItem},volantis.pjax=Object.assign(volantis.pjax,{push:volantis.pjax.method.complete.push,error:volantis.pjax.method.error.push,send:volantis.pjax.method.send.push}),volantis.rightmenu={},volantis.rightmenu.method={handle:new RunItem},volantis.rightmenu=Object.assign(volantis.rightmenu,{handle:volantis.rightmenu.method.handle.push}),volantis.dark={},volantis.dark.method={toggle:new RunItem},volantis.dark=Object.assign(volantis.dark,{push:volantis.dark.method.toggle.push}),volantis.js=(e,t)=>new Promise((n=>{setTimeout((function(){var o=document.getElementsByTagName("head")[0]||document.documentElement,l=document.createElement("script");if(l.setAttribute("type","text/javascript"),t)if(JSON.stringify(t))for(let e in t)"onload"==e?l[e]=()=>{t[e](),n()}:(l[e]=t[e],l.onload=n);else l.onload=()=>{t(),n()};else l.onload=n;l.setAttribute("src",e),o.appendChild(l)}))})),volantis.css=e=>new Promise((t=>{setTimeout((function(){var n=document.createElement("link");n.rel="stylesheet",n.href=e,n.onload=t,document.getElementsByTagName("head")[0].appendChild(n)}))})),volantis.import={jQuery:()=>"undefined"==typeof jQuery?volantis.js("https://cdn.bootcdn.net/ajax/libs/jquery/3.6.0/jquery.min.js"):new Promise((e=>{e()}))},volantis.throttle=(e,t=200)=>{let n=0;return function(...o){const l=Date.now();l-n>=t&&(e.apply(this,o),n=l)}},volantis.debounce=(e,t=200)=>{let n=null;return function(){n&&clearTimeout(n),n=setTimeout((()=>{e.apply(this,arguments),n=null}),t)}},volantis.requestAnimationFrame=e=>(window.requestAnimationFrame||(window.requestAnimationFrame=window.requestAnimationFrame||window.mozRequestAnimationFrame||window.webkitRequestAnimationFrame||function(e){return window.setTimeout(e,1e3/60)}),window.requestAnimationFrame(e)),volantis.layoutHelper=(e,t,n)=>{function o(e,t,n){volantis.tempDiv=document.createElement("div"),volantis.tempDiv.innerHTML=t;let o=document.querySelector("#layoutHelper-"+e);o&&(n&&(o.innerHTML=""),o.append(volantis.tempDiv))}n=Object.assign({clean:!1,pjax:!0},n),o(e,t,n.clean),n.pjax&&volantis.pjax.push((()=>{o(e,t,n.clean)}),"layoutHelper-"+e)},volantis.scroll={engine:new RunItem,unengine:new RunItem},volantis.scroll=Object.assign(volantis.scroll,{push:volantis.scroll.engine.push}),volantis.scroll.getScrollTop=()=>{let e;return window.pageYOffset?e=window.pageYOffset:document.compatMode&&"BackCompat"!=document.compatMode?e=document.documentElement.scrollTop:document.body&&(e=document.body.scrollTop),e},volantis.scroll.scrollHeight=function(){return Math.max(document.body.scrollHeight,document.documentElement.scrollHeight)},volantis.scroll.offsetHeight=function(){return Math.min(document.body.offsetHeight,document.documentElement.offsetHeight,document.body.clientHeight,document.documentElement.clientHeight)},volantis.scroll.progress=function(){return volantis.scroll.getScrollTop()/(volantis.scroll.scrollHeight()-volantis.scroll.offsetHeight())},volantis.scroll.handleScrollEvents=()=>{volantis.scroll.lastScrollTop=volantis.scroll.getScrollTop(),volantis.requestAnimationFrame((function e(){const t=volantis.scroll.getScrollTop();volantis.scroll.lastScrollTop!==t?(volantis.scroll.del=t-volantis.scroll.lastScrollTop,volantis.scroll.lastScrollTop=t,volantis.scroll.unengine.list=[],volantis.scroll.engine.start()):volantis.scroll.unengine.start(),volantis.requestAnimationFrame(e)}))},volantis.scroll.handleScrollEvents(),volantis.scroll.ele=null,volantis.scroll.to=(e,t={})=>{e&&(volantis.scroll.ele=e,opt={top:e.getBoundingClientRect().top+document.documentElement.scrollTop,behavior:"smooth"},"top"in t&&(opt.top=t.top),"behavior"in t&&(opt.behavior=t.behavior),"addTop"in t&&(opt.top+=t.addTop),"observerDic"in t||(t.observerDic=100),window.scrollTo(opt),t.observer&&setTimeout((()=>{volantis.scroll.ele==e&&volantis.scroll.unengine.push((()=>{let n=e.getBoundingClientRect().top;n>=-t.observerDic&&n<=t.observerDic||volantis.scroll.to(e,t),volantis.scroll.unengine.remove("unengineObserver")}),"unengineObserver")}),1e3))},volantis.cleanContentVisibility=()=>{document.querySelector(".post-story")&&(console.log("cleanContentVisibility"),document.querySelectorAll(".post-story").forEach((e=>{e.classList.remove("post-story")})))};const nativeSetTimeout=window.setTimeout,nativeSetInterval=window.setInterval,nativeClearTimeout=window.clearTimeout,nativeClearInterval=window.clearInterval;volantis.activeTimeout=[],volantis.activeInterval=[],window.setTimeout=function(e,t,...n){const o=nativeSetTimeout((function(...t){try{return e.apply(this,t)}finally{const e=volantis.activeTimeout.indexOf(o);-1!==e&&volantis.activeTimeout.splice(e,1)}}),t,...n);return volantis.activeTimeout.push(o),o},window.setInterval=function(e,t,...n){const o=nativeSetInterval(e,t,...n);return volantis.activeInterval.push(o),o},window.clearTimeout=function(e){nativeClearTimeout(e);const t=volantis.activeTimeout.indexOf(e);-1!==t&&volantis.activeTimeout.splice(t,1)},window.clearInterval=function(e){nativeClearInterval(e);const t=volantis.activeInterval.indexOf(e);-1!==t&&volantis.activeInterval.splice(t,1)},volantis.getActiveInterval=function(){return[...volantis.activeInterval]},volantis.getActiveTimeout=function(){return[...volantis.activeTimeout]},volantis.clearAllTimers=function(){volantis.getActiveInterval().forEach((function(e){clearInterval(e)})),volantis.getActiveTimeout().forEach((function(e){clearTimeout(e)}))},volantis.pjax.send(volantis.clearAllTimers,"clearAllTimers")</script><script>volantis.GLOBAL_CONFIG={root:"/",debug:!1,default:{avatar:"https://static.mhuig.top/npm/volantis-static@0.0.1660614606622/media/placeholder/avatar/round/3442075.svg",link:"https://static.mhuig.top/npm/volantis-static@0.0.1660614606622/media/placeholder/link/8f277b4ee0ecd.svg",cover:"https://static.mhuig.top/npm/volantis-static@0.0.1660614606622/media/placeholder/cover/76b86c0226ffd.svg",image:"https://static.mhuig.top/npm/volantis-static@0.0.1660614606622/media/placeholder/image/2659360.svg"},lastupdate:new Date(1779510804521),cdn:{izitoast_css:"https://cdn.bootcdn.net/ajax/libs/izitoast/1.4.0/css/iziToast.min.css",izitoast_js:"https://cdn.bootcdn.net/ajax/libs/izitoast/1.4.0/js/iziToast.min.js",fancybox_css:"https://cdn.bootcdn.net/ajax/libs/fancyapps-ui/4.0.31/fancybox.min.css",fancybox_js:"https://cdn.bootcdn.net/ajax/libs/fancyapps-ui/4.0.31/fancybox.umd.min.js"},sidebar:{for_page:["blogger","navigation","webinfo"],for_post:["toc"],webinfo:{lastupd:{enable:!1,friendlyShow:!0},runtime:{data:"2019/08/19",unit:"天"}}},plugins:{message:{enable:!1,icon:{default:"fa-solid fa-info-circle light-blue",quection:"fa-solid fa-question-circle light-blue"},time:{default:5e3,quection:2e4},position:"topRight",transitionIn:"bounceInLeft",transitionOut:"fadeOutRight",titleColor:"var(--color-text)",messageColor:"var(--color-text)",backgroundColor:"var(--color-card)",zindex:2147483647,copyright:{enable:!0,title:"知识共享许可协议",message:"请遵守 CC BY-NC-SA 4.0 协议。",icon:"far fa-copyright light-blue"},aplayer:{enable:!0,play:"fa-solid fa-play",pause:"fa-solid fa-pause"},rightmenu:{enable:!0,notice:!0}},aplayer:{id:1480000098,enable:!0}},search:{dataPath:("/".endsWith("/")?"/":"//")+"content.json"},languages:{search:{hits_empty:"找不到您查询的内容:${query}",hits_stats:"找到 ${hits} 条结果,用时 ${time} 毫秒"}}}</script><script type="application/ld+json">[{"@context":"http://schema.org","@type":"Organization","name":"MHuiG Magicland","url":"https://blog.mhuig.top/","logo":{"@type":"ImageObject","url":"/lib/favicon/android-chrome-192x192.png","width":192,"height":192}},{"@context":"http://schema.org","@type":"Person","name":"MHuiG","image":{"@type":"ImageObject","url":"/lib/favicon/android-chrome-192x192.png"},"url":"https://blog.mhuig.top/","sameAs":["https://github.com/MHuiG","https://twitter.com/iMHuiG","https://t.me/MHuiG","https://keybase.io/MHuiG"],"description":"「Be Yourself, Make a Difference.」"},{"@context":"http://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"item":{"@id":"https://blog.mhuig.top/","name":"Magicland"}},{"@type":"ListItem","position":2,"item":{"@id":"https://blog.mhuig.top/categories/历史/","name":"历史"}},{"@type":"ListItem","position":2,"item":{"@id":"https://blog.mhuig.top/categories/历史/Person/","name":"Person"}},{"@type":"ListItem","position":3,"item":{"@id":"https://blog.mhuig.top/notes/person/14.html","name":"von Neumann约翰·冯·诺依曼在数学与博弈论的多领域奠基性贡献"}}]},{"@context":"http://schema.org","@type":"WebSite","name":"MHuiG Magicland","url":"https://blog.mhuig.top/","keywords":"MHuiG, @MHuiG, Blog, 博客, Magicland, 魔法世界","description":"宠辱不惊,看庭前花开花落;去留无意,望天上云卷云舒。「Be Yourself, Make a Difference.」 - Magic Island","author":{"@type":"Person","name":"MHuiG","image":{"@type":"ImageObject","url":"/lib/favicon/android-chrome-192x192.png"},"url":"https://blog.mhuig.top/","description":"「Be Yourself, Make a Difference.」"},"publisher":{"@type":"Organization","name":"MHuiG Magicland","url":"https://blog.mhuig.top/","logo":{"@type":"ImageObject","url":"/lib/favicon/android-chrome-192x192.png","width":192,"height":192}},"potentialAction":{"@type":"SearchAction","name":"Coco | The Cat of MHuiG","target":{"@type":"EntryPoint","urlTemplate":"https://blog.mhuig.top/havefun/Coco/?s={search_term_string}"},"query-input":"required name=search_term_string"}},{"@context":"http://schema.org","@type":"BlogPosting","headline":"von Neumann约翰·冯·诺依曼在数学与博弈论的多领域奠基性贡献","description":"约翰·冯·诺依曼在数学领域贡献卓著,奠定了量子力学的数学基础,并与默里合作建立了冯·诺依曼代数。他在博弈论方面证明了极小极大定理,并与摩根斯坦合著了《博弈论与经济行为》。此外,他还严格证明了遍历定理。","inLanguage":"zh-Hans","mainEntityOfPage":{"@type":"WebPage","@id":"https://blog.mhuig.top/notes/person/14"},"author":{"@type":"Person","name":"MHuiG","image":{"@type":"ImageObject","url":"/lib/favicon/android-chrome-192x192.png"},"url":"https://blog.mhuig.top/"},"publisher":{"@type":"Organization","name":"MHuiG Magicland","logo":{"@type":"ImageObject","url":"/lib/favicon/android-chrome-192x192.png","width":192,"height":192}},"url":"https://blog.mhuig.top/notes/person/14","wordCount":0,"datePublished":"2026-05-10T00:07:00.000Z","dateModified":"2026-05-10T00:10:00.000Z","articleSection":"历史","keywords":"History,人物,冯·诺伊曼,算子代数,博弈论,遍历理论","image":{"@type":"ImageObject","url":"/lib/favicon/android-chrome-192x192.png","width":192,"height":192}}]</script></head><body itemscope="" itemtype="http://schema.org/WebPage"><pjax></pjax><header itemscope="" itemtype="http://schema.org/WPHeader" id="l_header" class="l_header auto shadow floatable blur show" style="opacity:0"><div class="container"><div id="wrapper"><div class="nav-sub"><p class="title"></p><ul class="switcher nav-list-h m-phone" id="pjax-header-nav-list"><li><a id="s-comment" class="fa-solid fa-comments fa-fw" target="_self" title="comment"></a></li><li><a id="s-toc" class="s-toc fa-solid fa-list fa-fw" target="_self" title="toc"></a></li></ul></div><div class="nav-main"> <a class="title flat-box" target="_self" href="/">MHuiG</a><div class="menu navigation"><ul class="nav-list-h m-pc"><li><a class="menuitem flat-box faa-parent animated-hover" title="索引"><i class="fa-duotone fa-list-alt fa-fw"></i> 索引</a><ul class="list-v"><li><a class="menuitem flat-box faa-parent animated-hover" href="/notes/" title="便签" active-action="action-notes"><i class="fa-duotone fa-books fa-fw"></i> 便签</a></li><li><a class="menuitem flat-box faa-parent animated-hover" href="/categories/" title="分类" active-action="action-categories"><i class="fa-duotone fa-folder-open fa-fw"></i> 分类</a></li><li><a class="menuitem flat-box faa-parent animated-hover" href="/tags/" title="标签" active-action="action-tags"><i class="fa-duotone fa-tags fa-fw"></i> 标签</a></li><li><a class="menuitem flat-box faa-parent animated-hover" href="/archives/" title="归档" active-action="action-archives"><i class="fa-duotone fa-archive fa-fw"></i> 归档</a></li></ul></li><li><a class="menuitem flat-box faa-parent animated-hover" href="/pages/friends/" title="友链" active-action="action-pagesfriends"><i class="fa-duotone fa-link fa-fw"></i> 友链</a><ul class="list-v"><li><a class="menuitem flat-box faa-parent animated-hover" href="https://www.travellings.cn/go-by-clouds.html" title="Travelling" target="_blank" active-action="action-https:wwwtravellingscngo-by-cloudshtml" rel="external nofollow noopener noreferrer"><i class="fa-duotone fa-subway fa-fw"></i> Travelling</a></li></ul></li><li><a class="menuitem flat-box faa-parent animated-hover" href="/pages/about/" title="关于" active-action="action-pagesabout"><i class="fa-duotone fa-user-tie fa-fw"></i> 关于</a><ul class="list-v"><li><a class="menuitem flat-box faa-parent animated-hover" href="/pages/time-machine/" title="时光机" active-action="action-pagestime-machine"><i class="fa-duotone fa-clock fa-fw"></i> 时光机</a></li><li><a class="menuitem flat-box faa-parent animated-hover" target="_blank" rel="noopener" href="https://mhuig.top/privacy-policy/" title="隐私政策" active-action="action-https:mhuigtopprivacy-policy"><i class="fa-duotone fa-user-secret fa-fw"></i> 隐私政策</a></li></ul></li><li><a class="menuitem flat-box faa-parent animated-hover" title="更多"><i class="fa-duotone fa-fan fa-spin fa-fw"></i> 更多</a><ul class="list-v"><li><a class="menuitem flat-box faa-parent animated-hover" href="/pages/beer/" title="Sponsor" active-action="action-pagesbeer"><i class="fa-duotone fa-heart-square fa-fw"></i> Sponsor</a></li><hr><li><a class="menuitem flat-box faa-parent animated-hover" title="博客管理"><i class="fa-duotone fa-user-shield fa-fw"></i> 博客管理</a><ul class="list-v"><li><a class="menuitem flat-box header toggle-mode-btn"><i class="fa-duotone fa-bat fa-fw"></i> 暗黑模式</a></li><li></li><li><a class="menuitem flat-box faa-parent animated-hover" href="/pages/rss/" title="RSS订阅" active-action="action-pagesrss"><i class="fa-duotone fa-rss fa-fw"></i> RSS订阅</a></li><li><a class="menuitem flat-box faa-parent animated-hover" href="/sitemap.xml" title="站点地图" active-action="action-sitemapxml"><i class="fa-duotone fa-sitemap fa-fw"></i> 站点地图</a></li><li><a class="menuitem flat-box faa-parent animated-hover" target="_blank" rel="external nofollow noopener noreferrer" href="https://mhuig.instatus.com/" title="Monitors" active-action="action-https:mhuiginstatuscom"><i class="fa-duotone fa-telescope fa-fw"></i> Monitors</a></li><li><a class="menuitem flat-box faa-parent animated-hover" target="_blank" rel="external nofollow noopener noreferrer" href="https://ssl.mhuig.top/" title="SSL Status" active-action="action-https:sslmhuigtop"><i class="fa-brands fa-expeditedssl fa-fw"></i> SSL Status</a></li></ul></li><hr><li><a class="menuitem flat-box faa-parent animated-hover" title="工具箱"><i class="fa-duotone fa-tools fa-fw"></i> 工具箱</a><ul class="list-v"><li><a class="menuitem flat-box faa-parent animated-hover" target="_blank" rel="external nofollow noopener noreferrer" href="https://rssbox.mhuig.top/" title="RSS Box" active-action="action-https:rssboxmhuigtop"><i class="fa-duotone fa-conveyor-belt-boxes fa-fw"></i> RSS Box</a></li><li><a class="menuitem flat-box faa-parent animated-hover" href="/havefun/Coco/" title="My Cat" active-action="action-havefunCoco"><i class="fa-duotone fa-cat fa-fw"></i> My Cat</a></li><li><a class="menuitem flat-box"><i class="fa-duotone fa-compact-disc fa-spin fa-fw music"></i> Music</a><ul class="list-v"><li><div class="aplayer-container"><div class="aplayer-local"></div></div></li></ul></li><li></li><li><a class="menuitem flat-box faa-parent animated-hover" href="/pages/talk/" title="碎言碎语" active-action="action-pagestalk"><i class="fa-duotone fa-comments fa-fw"></i> 碎言碎语</a></li></ul></li><hr><li><a class="menuitem flat-box faa-parent animated-hover" target="_blank" rel="external nofollow noopener noreferrer" href="https://github.com/MHuiG" title="GitHub" active-action="action-https:githubcomMHuiG"><i class="fa-brands fa-github fa-fw"></i> GitHub</a></li></ul></li></ul></div><div class="m_search"><form name="searchform" class="form u-search-form"><i class="icon fa-solid fa-search fa-fw"></i> <input type="text" class="input u-search-input" placeholder="Search..."></form></div><ul class="switcher nav-list-h m-phone"><li><a class="s-search fa-solid fa-search fa-fw" target="_self" title="search"></a></li><li><a class="s-menu fa-solid fa-bars fa-fw" target="_self" title="menu"></a><ul class="menu-phone list-v navigation white-box"><li><a class="menuitem flat-box faa-parent animated-hover" title="索引"><i class="fa-duotone fa-list-alt fa-fw"></i> 索引</a><ul class="list-v"><li><a class="menuitem flat-box faa-parent animated-hover" href="/notes/" title="便签" active-action="action-notes"><i class="fa-duotone fa-books fa-fw"></i> 便签</a></li><li><a class="menuitem flat-box faa-parent animated-hover" href="/categories/" title="分类" active-action="action-categories"><i class="fa-duotone fa-folder-open fa-fw"></i> 分类</a></li><li><a class="menuitem flat-box faa-parent animated-hover" href="/tags/" title="标签" active-action="action-tags"><i class="fa-duotone fa-tags fa-fw"></i> 标签</a></li><li><a class="menuitem flat-box faa-parent animated-hover" href="/archives/" title="归档" active-action="action-archives"><i class="fa-duotone fa-archive fa-fw"></i> 归档</a></li></ul></li><li><a class="menuitem flat-box faa-parent animated-hover" href="/pages/friends/" title="友链" active-action="action-pagesfriends"><i class="fa-duotone fa-link fa-fw"></i> 友链</a><ul class="list-v"><li><a class="menuitem flat-box faa-parent animated-hover" href="https://www.travellings.cn/go-by-clouds.html" title="Travelling" target="_blank" active-action="action-https:wwwtravellingscngo-by-cloudshtml" rel="external nofollow noopener noreferrer"><i class="fa-duotone fa-subway fa-fw"></i> Travelling</a></li></ul></li><li><a class="menuitem flat-box faa-parent animated-hover" href="/pages/about/" title="关于" active-action="action-pagesabout"><i class="fa-duotone fa-user-tie fa-fw"></i> 关于</a><ul class="list-v"><li><a class="menuitem flat-box faa-parent animated-hover" href="/pages/time-machine/" title="时光机" active-action="action-pagestime-machine"><i class="fa-duotone fa-clock fa-fw"></i> 时光机</a></li><li><a class="menuitem flat-box faa-parent animated-hover" target="_blank" rel="noopener" href="https://mhuig.top/privacy-policy/" title="隐私政策" active-action="action-https:mhuigtopprivacy-policy"><i class="fa-duotone fa-user-secret fa-fw"></i> 隐私政策</a></li></ul></li><li><a class="menuitem flat-box faa-parent animated-hover" title="更多"><i class="fa-duotone fa-fan fa-spin fa-fw"></i> 更多</a><ul class="list-v"><li><a class="menuitem flat-box faa-parent animated-hover" href="/pages/beer/" title="Sponsor" active-action="action-pagesbeer"><i class="fa-duotone fa-heart-square fa-fw"></i> Sponsor</a></li><hr><li><a class="menuitem flat-box faa-parent animated-hover" title="博客管理"><i class="fa-duotone fa-user-shield fa-fw"></i> 博客管理</a><ul class="list-v"><li><a class="menuitem flat-box header toggle-mode-btn"><i class="fa-duotone fa-bat fa-fw"></i> 暗黑模式</a></li><li></li><li><a class="menuitem flat-box faa-parent animated-hover" href="/pages/rss/" title="RSS订阅" active-action="action-pagesrss"><i class="fa-duotone fa-rss fa-fw"></i> RSS订阅</a></li><li><a class="menuitem flat-box faa-parent animated-hover" href="/sitemap.xml" title="站点地图" active-action="action-sitemapxml"><i class="fa-duotone fa-sitemap fa-fw"></i> 站点地图</a></li><li><a class="menuitem flat-box faa-parent animated-hover" target="_blank" rel="external nofollow noopener noreferrer" href="https://mhuig.instatus.com/" title="Monitors" active-action="action-https:mhuiginstatuscom"><i class="fa-duotone fa-telescope fa-fw"></i> Monitors</a></li><li><a class="menuitem flat-box faa-parent animated-hover" target="_blank" rel="external nofollow noopener noreferrer" href="https://ssl.mhuig.top/" title="SSL Status" active-action="action-https:sslmhuigtop"><i class="fa-brands fa-expeditedssl fa-fw"></i> SSL Status</a></li></ul></li><hr><li><a class="menuitem flat-box faa-parent animated-hover" title="工具箱"><i class="fa-duotone fa-tools fa-fw"></i> 工具箱</a><ul class="list-v"><li><a class="menuitem flat-box faa-parent animated-hover" target="_blank" rel="external nofollow noopener noreferrer" href="https://rssbox.mhuig.top/" title="RSS Box" active-action="action-https:rssboxmhuigtop"><i class="fa-duotone fa-conveyor-belt-boxes fa-fw"></i> RSS Box</a></li><li><a class="menuitem flat-box faa-parent animated-hover" href="/havefun/Coco/" title="My Cat" active-action="action-havefunCoco"><i class="fa-duotone fa-cat fa-fw"></i> My Cat</a></li><li><a class="menuitem flat-box faa-parent animated-hover" href="/pages/talk/" title="碎言碎语" active-action="action-pagestalk"><i class="fa-duotone fa-comments fa-fw"></i> 碎言碎语</a></li></ul></li><hr><li><a class="menuitem flat-box faa-parent animated-hover" target="_blank" rel="external nofollow noopener noreferrer" href="https://github.com/MHuiG" title="GitHub" active-action="action-https:githubcomMHuiG"><i class="fa-brands fa-github fa-fw"></i> GitHub</a></li></ul></li></ul></li></ul></div></div></div></header><div id="l_body"><div id="l_cover"><div id="none" class="cover-wrapper docs featured" style="display:none"><div class="cover-bg lazyload placeholder" data-bg=""></div><div class="cover-body"><div class="top"><p class="title">Magicland</p><p class="subtitle">「看庭前花开花落,望天上云卷云舒」</p></div><div class="bottom"><div class="menu navigation"><div class="list-h"><a target="_blank" rel="external nofollow noopener noreferrer" href="https://github.com/MHuiG" active-action="action-https:githubcomMHuiG"><i class="fa-brands fa-github color-github fa-fw"></i><p>Github</p></a><a href="/pages/friends/" active-action="action-pagesfriends"><i class="fa-duotone fa-link color-friends fa-fw"></i><p>友链</p></a><a href="/pages/about/" active-action="action-pagesabout"><i class="fa-duotone fa-user-tie color-about fa-fw"></i><p>关于</p></a><a href="https://www.travellings.cn/go-by-clouds.html" target="_blank" active-action="action-https:wwwtravellingscngo-by-cloudshtml" rel="external nofollow noopener noreferrer"><i class="fa-duotone fa-subway color-travellings fa-fw"></i><p>Travelling</p></a></div></div></div></div><div id="scroll-down" style="display:none"><i class="fa fa-chevron-down scroll-down-effects"></i></div></div></div><div id="safearea"><div class="body-wrapper"><div id="l_main" class=""><article itemscope="" itemtype="http://schema.org/Article" class="article post white-box reveal md shadow floatable blur article-type-docs" id="docs" itemprop="blogPost"><link itemprop="mainEntityOfPage" href="https://blog.mhuig.top/notes/person/14"><span hidden="" itemprop="publisher" itemscope="" itemtype="http://schema.org/Organization"><meta itemprop="name" content="Magicland"></span><span hidden="" itemprop="post" itemscope="" itemtype="http://schema.org/CreativeWork"><meta itemprop="name" content="von Neumann约翰·冯·诺依曼在数学与博弈论的多领域奠基性贡献"><meta itemprop="description" content="约翰·冯·诺依曼在数学领域贡献卓著,奠定了量子力学的数学基础,并与默里合作建立了冯·诺依曼代数。他在博弈论方面证明了极小极大定理,并与摩根斯坦合著了《博弈论与经济行为》。此外,他还严格证明了遍历定理。"></span><span hidden=""><meta itemprop="image" content="/lib/favicon/android-chrome-192x192.png"></span><div class="article-meta" id="top"><span hidden="" itemprop="name headline"></span></div><div id="layoutHelper-page-plugins"></div><div id="post-body" itemprop="articleBody"><p> <span class="p logo center large">von Neumann</span></p><br><h1 hidden="">von Neumann</h1><div class="story post-story"><h2 id="生平"><a href="#生平" class="headerlink" title="生平"></a>生平</h2><p>约翰・冯・诺伊曼(John von Neumann,1903-1957)出生时名为 “Neumann János Lajos”,后来在美国,他被称为 Johnny。</p><p>von Neumann 的父亲马克思・诺伊曼(Max von Neumann)是一位顶尖的银行家,他在一个大家庭中长大,居住在匈牙利布达佩斯。小时候,他跟随家中聘请的德国和法国女家庭教师学习语言。</p><p>尽管这个家庭是犹太人,但 Max Neumann 并不遵守严格的宗教习俗,家中似乎融合了犹太和基督教的传统。</p><p>由于对当时繁荣的匈牙利经济作出了贡献,Max Neumann 有资格申请世袭头衔,并于 1913 年获得了 “Margittai” 的世袭称号,但他并未更改自己的姓氏。后来,他的儿子在名字中使用了德语形式 von Neumann,其中 “von” 表示这个头衔。</p><p>孩童时期的 von Neumann 展现出了惊人的记忆力。</p><p>Poundstone 在回忆中写道:“在六岁时,他就能够用古典希腊语和父亲开玩笑。Neumann 家有时会让 Johnny 展示他记忆电话簿的能力来招待客人。一位客人会随意选择电话簿中的某一页和某一栏,年幼的 Johnny 会看上几遍,然后把电话簿还给客人。他能够回答任何与此相关的问题(‘某某号码是谁的?’),或者按照顺序背出姓名、地址和电话号码。”</p><p>1914 年,von Neumann 进入路德的中学 Fasori Evangélikus Gimnázium 就读。Eugene Wigner 比 von Neumann 高一年级,很快就与他成为朋友。</p><p>虽然 von Neumann 的父亲坚持让他按照同龄人的年级正常上学,但也同意聘请私人教师对他进行高阶辅导。</p><p>十五岁时,von Neumann 开始在分析学家 Gábor Szegő 的指导下学习高等微积分。据 Szegő 的妻子回忆,俩人第一次见面时,von Neumann 展现出的数学天赋与思维速度令 Szegő 震惊不已,他回到家后甚至感动得热泪盈眶。</p><p>到了十九岁,von Neumann 已发表了两篇重要的数学论文。他的第一篇数学论文《关于某些最小多项式的零点位置》(On the position of zeroes of certain minimum polynomials)是与布达佩斯大学的助教费克特(Michael Fekete,1886-1957)共同撰写的,该论文于 1922 年发表。<br>第二篇给出了序数(ordinal numbers)的现代定义,取代了 Georg Cantor 的旧定义。完成中学学业后,他申请并获得了匈牙利全国性的数学奖 ——Eötvös Prize。</p><p>然而,Max Neumann 不希望儿子投身一个无法带来财富的学科,于是请冯・卡门(Theodore von Kármán,1881-1963)出面,与 von Neumann 交谈,劝他从商。<br>或许 von Kármán 并不是最合适的人选,不过最终他们达成妥协,让 von Neumann 在大学主修化学。</p><p>由于种种原因,对于犹太裔而言,匈牙利并不是一个友善的国家,而且布达佩斯大学对犹太学生人数有严格限制。即使有配额,von Neumann 的成绩依然足以在 1921 年赢得一个数学专业的名额,但他并没有去听课。相反,他在同一年还进入了柏林大学(University of Berlin)学习化学。von Neumann 在柏林大学学习化学至 1923 年,随后前往苏黎世(Zürich)。尽管他没有参加任何课程,仍在布达佩斯大学的数学考试中取得了优异成绩。</p><p>1926 年,von Neumann 在苏黎世高等工业学院(Technische Hochschule in Zürich)获得化学工程文凭。在苏黎世期间,他尽管主修化学,但依旧对数学抱有极大兴趣,并与当时在苏黎世的外尔(Hermann Weyl, 1885-1955)和波利亚(George Pólya, 1887-1985)保持学术交流。</p><p>某段时间,当 Weyl 离开苏黎世时,von Neumann 甚至代为讲授了他的课程。</p><p>Pólya 在采访中曾说道:“Johnny 是我唯一惧怕过的学生。如果我在课堂上提出了一个尚未解决的问题,通常一等下课,他就能拿着在纸片上匆匆写下的完整解答来找我。”</p><p>1926 年,von Neumann 在布达佩斯大学也获得了数学博士学位,他的博士论文是对康托尔集合论(Cantor's set theory)进行公理化研究。</p><p>20 岁时,他发表了一个对序数(ordinal numbers)的定义,至今仍在使用。</p><p>von Neumann 于 1926 年至 1929 年在柏林(Berlin)授课,1929 年至 1930 年在汉堡(Hamburg)授课。</p><p>他还获得了洛克菲勒基金会(Rockefeller Fellowship)的资助,得以在哥廷根大学(University of Göttingen)从事博士后研究,在希尔伯特(David Hilbert, 1862-1943)门下研究数学。</p><p>到了这个时候,von Neumann 已经在数学界声名鹊起:“二十多岁时,von Neumann 在数学界已是名声远播。学术会议上,人们会指着他称其为年轻天才。”</p><p>Hermann Weyl 回忆说,在 1926 至 1927 年的冬季学期,von Neumann、艾米・诺特(Emmy Noether, 1882-1935)和他常常在 “哥廷根寒冷潮湿的街道上” 边走边讨论超复数(hypercomplex numbers)体系及其表示。</p><p>维布伦(Oswald Veblen, 1880-1960)于 1929 年邀请 John von Neumann 前往普林斯顿(Princeton)讲授量子理论。von Neumann 回复说他会先处理一些个人事务,然后再动身前往普林斯顿;于是他先回到布达佩斯,与未婚妻玛丽埃塔・科韦西(Marietta Kovesi)成婚后,才前往美国。</p><p>1930 年,von Neumann 成为普林斯顿大学的客座讲师,并于 1931 年被任命为教授。</p><p>在 1930 至 1933 年间,von Neumann 在普林斯顿任教,但教学并不是他的强项之一:“他奔放的思维对天赋没那么高的学生而言实在难以跟上。他在仅占黑板一小部分的地方飞快地写下推导,然后在学生还没来得及抄写前就把它们擦掉了,这在当时很出名。”</p><p>然而,与之形成对比的是,他在解释物理中的复杂概念时却拥有出众的能力:“对于一个能够轻松应对复杂数学的人,他向外行解释结论时却能展现出惊人的清晰度。和他交谈后,人们常会觉得原来的问题其实简单而透明。”</p><p>If people do not believe that mathematics is simple, it is only because they do not realize how complicated life is.<br>— John von Neumann</p><p>1933 年,他成为新成立的普林斯顿高等研究院(IAS)最初六位数学教授(亚历山大(James Waddell Alexander, 1888-1971)、爱因斯坦(Albert Einstein, 1879-1955)、莫尔斯(Marston Morse, 1892-1977)、Veblen、von Neumann 和 Weyl)之一,并一直在该研究院任职直到去世。</p><p>在刚到美国的头几年里,von Neumann 夏天仍会回到欧洲。1933 年之前,他依然在德国有学术职位,但纳粹上台后他就辞去了这些职位。</p><p>与许多政治难民不同,von Neumann 来到美国主要是因为他认为美国的学术职位前景比德国更好。</p><p>1935 年,von Neumann 和 Marietta 育有一个女儿 Marina,但他们的婚姻于 1937 年以离婚告终。第二年,他与同样来自布达佩斯的 Klára Dán 结婚。von Neumann 是在一次回欧洲时与她相识的。婚后,两人乘船前往美国,并在普林斯顿定居。在那里,von Neumann 过着与其他顶尖数学家不太一样的生活方式。他一直热衷于社交聚会:“von Neumann 对聚会和夜生活有种特别的喜好。早在德国任教时,他便是柏林歌舞表演(Cabaret)时代夜生活圈子中的常客。”</p><p>乌拉姆(Stanisław Marcin Ulam, 1909-1984)对 von Neumann 的研究工作作了总结。他写道:“在他早期的研究中,他不仅关注数学逻辑和集合论的公理化,同时也研究集合论本身,在测度论和实变函数论中取得了有趣的成果。正是在这段时期,他开始了关于量子理论的经典研究,尤其是量子理论的测量理论以及新的统计力学的数学基础。”</p><p>他的著作《量子力学的数学基础》(Mathematische Grundlagen der Quantenmechanik, 1932 年)为新的量子力学奠定了坚实的框架。</p><p>1929 年,von Neumann 在发表于《Mathematische Annalen》的一篇论文中引入了在弱算子拓扑下闭的、作用于 Hilbert 空间的有界线性算子自伴代数(self-adjoint algebras)。</p><p>卡迪森(Richard Vincent Kadison, 1925-2018)解释道:<br>“他对遍历理论(ergodic theory)、群表示以及量子力学的兴趣,为他认识到算子代数理论(operator algebras)是这一数学领域下一重要发展阶段起到了显著作用。”</p><p>当时他使用的术语是 “rings of operators”,而之后有些数学家称它们为<mjx-container class="MathJax" jax="SVG" overflow="overflow"><svg style="vertical-align:-.05ex" xmlns="http://www.w3.org/2000/svg" width="3.484ex" height="1.61ex" role="img" focusable="false" viewBox="0 -689.7 1539.8 711.7"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(1,-1)"><g data-mml-node="math" data-latex="W^*"><g data-mml-node="msup" data-latex="W^*"><g data-mml-node="mi" data-latex="W"><path data-c="1D44A" d="M956 680C937 680 872 683 853 683 838 683 830 675 830 660 830 650 836 645 848 644 885 643 903 632 903 610 903 604 899 594 891 579L629 125 594 602C590 638 614 644 659 644 680 644 690 652 690 668 690 678 684 683 671 683 649 683 572 680 550 680 531 680 465 683 446 683 431 683 423 675 423 659 423 649 432 644 451 644 482 644 498 637 499 623L505 548 261 125 225 613C222 638 264 644 296 644 313 644 321 652 321 668 321 678 315 683 303 683 281 683 203 680 181 680 162 680 96 683 77 683 62 683 55 675 55 660 55 649 65 644 84 644 126 644 130 642 132 612L177 7C178-12 185-22 197-22 210-20 215-17 223-2 224-1 224 0 224 1L509 494 545 7C546-12 553-22 565-22 575-22 584-15 592-1L918 562C945 611 964 639 1025 644 1043 646 1048 651 1048 668 1048 678 1043 683 1032 683 1018 683 970 680 956 680Z"></path></g><g data-mml-node="mo" transform="translate(1136.2,363) scale(0.707)" data-latex="*"><path data-c="2217" d="M404 372C397 372 390 370 385 366L267 279 282 425C285 445 269 462 250 462 231 462 215 445 218 425L233 279 115 366C110 370 103 372 96 372 78 372 63 357 63 339 63 325 70 315 83 309L217 250 83 191C70 185 63 175 63 161 63 143 78 128 96 128 103 128 110 130 115 134L233 221 218 75C215 55 231 39 250 39 269 39 285 55 282 75L267 221 385 134C390 130 397 128 404 128 415 128 424 133 431 142 446 162 435 183 417 191L283 250 417 309C430 315 437 325 437 339 437 357 422 372 404 372Z"></path></g></g></g></g></svg></mjx-container> - 代数。1957 年,J Dixmier 在他著作《Algebras of operators in Hilbert space》中将它们称为 “von Neumann algebras”。</p><p>在 20 世纪 30 年代后期至 40 年代初,John von Neumann 与合作者 F J Murray 合作,奠定了研究 von Neumann 代数的基础,并在一系列具有重大影响的论文中系统展开了这一领域。</p><p>然而,人们更熟知的是 von Neumann 在各个不同科学领域都作出了多样化的研究成果。</p><p>正如 Ulam 在回忆中写的,他是这样走向博弈论的:</p><p>“von Neumann 对其他数学家已有成果的了解,以及他能从中看出的潜在可能性,着实令人惊叹。他的早期工作中,波莱尔(Félix Édouard Justin Émile Borel, 1871-1956)关于极小极大性质的一篇论文启发他发展…… 一些想法,最终在他的最具原创性的工作之一 —— 博弈论 —— 中结出了硕果。”</p><p>在博弈论中,von Neumann 证明了<br>极小极大定理(minimax theorem)。</p><p>他逐渐扩展在博弈论方面的研究,并与合作者摩根斯特恩(Oskar Morgenstern, 1902-1977)合著了经典著作《博弈论与经济行为》(Theory of games and Economic Behaviour)(1944)。</p><p>Ulam 继续写道:“库普曼(Bernard Osgood Koopman, 1900-1981)针对如何利用作用于函数空间的算子来处理经典力学问题的一些想法,激发了 von Neumann 给出第一个严格数学意义上的遍历定理证明。哈尔(Alfréd Haar, 1885-1933)在群上构造测度的方法,又激发了他对希尔伯特第五问题的出色部分解:在这一工作中,他证明了在紧群上引入解析参数的可能性。”</p><p>1930 年代中期,von Neumann 转向了应用数学的研究:</p><p>“30 年代中期,他对流体力学湍流问题产生了浓厚兴趣。当时他已经意识到,非线性偏微分方程背后隐藏着无数神秘之处。从二战开始,他致力流体力学方程与激波理论的研究。这些非线性方程所描述的现象在解析上极其困难,用现有方法连定性理解都很难实现。进行数值计算在他看来是获得对此类系统行为认识的最有前景的途径。这也促使他进一步研究如何借助电子设备进行全新的计算……”</p><p>John von Neumann 是计算机科学的先驱之一,为逻辑设计的发展作出了重大贡献。香农(Claude Shannon, 1916-2001)写道:“在他生命的最后几年里,von Neumann 相当大一部分时间都致力于研究自动机理论(automata theory)。对他而言,这个领域可以视为他早年对逻辑和证明论兴趣,与他在二战期间及战后对大型电子计算机的研究之间的一种综合。自动机理论本身融合了纯数学、应用数学以及其他科学门类,正好契合 von Neumann 博大精深的智慧。他带来了许多全新的洞见,并开辟了至少两个新的研究方向。”</p><p>他推动了元胞自动机(cellular automata)的理论研究,倡导使用 “比特” 作为计算机内存的度量单位,并在如何让不可靠的计算机元件输出可靠结果方面取得了突破。</p><p>二战期间以及战后,von Neumann 担任了多项与军方相关的顾问工作。他的贡献包括提出使用内爆法(implosion method)来使核燃料产生爆炸,并参与了氢弹的研制。</p><p>自 1940 年起,他一直是位于马里兰州阿伯丁试验场的弹道研究实验室(Ballistic Research Laboratories)科学顾问委员会的成员;1941 年至 1955 年,他是美国海军军械局(Navy Bureau of Ordnance)的成员;1943 年至 1955 年,他是洛斯阿拉莫斯科学实验室(Los Alamos Scientific Laboratory)的顾问;1950 年至 1955 年,他担任华盛顿特区武装部队特种武器项目(Armed Forces Special Weapons Project)的成员。</p><p>1955 年,艾森豪威尔(Dwight David Eisenhower, 1890-1969)总统任命他进入美国原子能委员会(Atomic Energy Commission),1956 年,当他已确诊患上无法治愈的癌症时,他依旧获得了该委员会的恩里科・费米奖(Enrico Fermi Award)。</p><p>Eugene Wigner 在回忆中写道 von Neumann 的去世:</p><p>“当 von Neumann 意识到自己不治之症时,他的逻辑让他不得不面对自己将不复存在、因而再也无法思考的事实…… 看着他在没有任何希望的情况下与自己认为不可避免但又无法接受的命运抗争,令人心碎。”</p><p>诺伊曼 1957 年因患癌症去世,年仅 53 岁。死后葬于新泽西州普林斯顿公墓</p><p>von Neumann 获得过两枚总统颁发的奖章:1947 年的功绩勋章(Medal for Merit)以及 1956 年的自由勋章(Medal for Freedom)。同样在 1956 年,他还获得了阿尔伯特・爱因斯坦纪念奖(Albert Einstein Commemorative Award)以及前文提到的恩里科・费米奖。</p><p>在数学、信息学有多个领域的国际奖项以 von Neumann 命名。月球背面的一个陨石坑和一颗小行星 22824 以纪念 von Neumann 而命名。</p></div><div class="story post-story"><h2 id="贡献"><a href="#贡献" class="headerlink" title="贡献"></a>贡献</h2><h3 id="一、集合论"><a href="#一、集合论" class="headerlink" title="一、集合论"></a>一、集合论</h3><p>在 1925 年的博士论文中,John von Neumann 针对朴素集合论(Naive set theory)中 “自包含” 集合问题(Russell's paradox)提出了两项关键方案:<br>其一是,基础公理(axiom of foundation),<br>其二是,“类”(class)的概念。</p><p>von Neumann 通过基础公理提出了任何集合可以用一类方法构造(The axiom of foundation proposed that every set can be constructed from the bottom up in an ordered succession of steps by way of the Zermelo–Fraenkel principles),进而排除了 “集合属于自身” 的可能性,同时为了证明新引入的公理不会和已有公理产生矛盾, von Neumann 引入了 inner models 的概念作为证明工具。</p><p>在严格集合的公理化体系的同时,von Neumann 确立了序数(ordinal)与基数(cardinal)理论的优雅架构,并首次严格地阐述了运用超限归纳(transfinite induction)进行定义的原则,对现代集合论的发展影响深远。</p><h3 id="二、冯·诺伊曼悖论(von-Neumann-paradox)"><a href="#二、冯·诺伊曼悖论(von-Neumann-paradox)" class="headerlink" title="二、冯·诺伊曼悖论(von Neumann paradox)"></a>二、冯・诺伊曼悖论(von Neumann paradox)</h3><p>在 Hausdorff 悖论的基础上,巴拿赫(Stefan Banach, 1892-1945)与塔斯基(Alfred Tarski, 1901-1983)于 1924 年基于选择公理证明了著名的巴拿赫 - 塔斯基悖论(Banach-Tarski paradox)。</p><p>这个悖论是说,对于三维空间中的单位球<mjx-container class="MathJax" jax="SVG" overflow="overflow"><svg style="vertical-align:0" xmlns="http://www.w3.org/2000/svg" width="1.717ex" height="1.545ex" role="img" focusable="false" viewBox="0 -683 759 683"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(1,-1)"><g data-mml-node="math" data-latex="B"><g data-mml-node="mi" data-latex="B"><path data-c="1D435" d="M756 543C756 634 666 683 568 683L236 683C213 683 203 682 203 659 203 643 223 644 235 644 265 643 283 641 288 640 293 639 295 636 295 631 295 629 294 623 291 613L159 82C154 60 144 47 129 42 122 40 104 39 73 39 52 39 42 31 42 15 42 5 52 0 73 0L426 0C491 0 551 20 608 59 671 102 703 155 703 217 703 296 638 344 567 358 655 379 756 446 756 543M554 644C623 644 658 612 658 547 658 496 638 454 596 420 554 386 507 370 456 370L317 370 377 610C385 644 385 644 427 644M582 299C596 276 603 253 603 228 603 176 583 131 542 94 501 57 455 39 402 39L267 39C257 39 250 39 246 40 240 40 237 42 237 45 237 46 237 49 238 53 269 180 293 276 309 340L493 340C536 340 565 326 582 299Z"></path></g></g></g></svg></mjx-container> ,我们将它分割成有限的若干部分<mjx-container class="MathJax" jax="SVG" overflow="overflow"><svg style="vertical-align:-.339ex" xmlns="http://www.w3.org/2000/svg" width="2.685ex" height="1.959ex" role="img" focusable="false" viewBox="0 -716 1186.6 866"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(1,-1)"><g data-mml-node="math" data-latex="A_1"><g data-mml-node="msub" data-latex="A_1 "><g data-mml-node="mi" data-latex="A"><path data-c="1D434" d="M137 3C155 3 217 0 236 0 251 0 258 8 258 23 258 32 252 38 239 39 210 40 196 50 196 69 196 78 205 98 224 128 251 173 270 206 283 228L526 228C526 221 527 207 530 185 537 112 541 72 541 67 541 48 519 39 474 39 455 39 446 31 446 15 446 5 452 0 464 0 488 0 564 3 588 3 608 3 679 0 699 0 714 0 721 8 721 24 721 34 712 39 694 39 666 39 649 41 644 44 639 47 635 56 634 71L574 689C571 708 572 716 551 716 539 716 529 710 522 697L178 120C148 70 108 43 59 39 43 38 35 30 35 15 35 5 41 0 52 0 68 0 121 3 137 3M492 577 522 267 307 267Z"></path></g><g data-mml-node="mn" transform="translate(783,-150) scale(0.707)" data-latex="1"><path data-c="31" d="M269 666C228 624 168 603 89 603L89 564C141 564 184 572 217 588L217 82C217 64 213 52 204 47 195 42 170 39 130 39L95 39 95 0C120 2 174 3 257 3 340 3 394 2 419 0L419 39 384 39C343 39 318 42 310 47 302 52 297 64 297 82L297 636C297 660 295 666 269 666Z"></path></g></g></g></g></svg></mjx-container>、…、<mjx-container class="MathJax" jax="SVG" overflow="overflow"><svg style="vertical-align:-.357ex" xmlns="http://www.w3.org/2000/svg" width="2.844ex" height="1.977ex" role="img" focusable="false" viewBox="0 -716 1257.3 873.8"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(1,-1)"><g data-mml-node="math" data-latex="A_n"><g data-mml-node="msub" data-latex="A_n"><g data-mml-node="mi" data-latex="A"><path data-c="1D434" d="M137 3C155 3 217 0 236 0 251 0 258 8 258 23 258 32 252 38 239 39 210 40 196 50 196 69 196 78 205 98 224 128 251 173 270 206 283 228L526 228C526 221 527 207 530 185 537 112 541 72 541 67 541 48 519 39 474 39 455 39 446 31 446 15 446 5 452 0 464 0 488 0 564 3 588 3 608 3 679 0 699 0 714 0 721 8 721 24 721 34 712 39 694 39 666 39 649 41 644 44 639 47 635 56 634 71L574 689C571 708 572 716 551 716 539 716 529 710 522 697L178 120C148 70 108 43 59 39 43 38 35 30 35 15 35 5 41 0 52 0 68 0 121 3 137 3M492 577 522 267 307 267Z"></path></g><g data-mml-node="mi" transform="translate(783,-150) scale(0.707)" data-latex="n"><path data-c="1D45B" d="M537 137C514 58 481 18 440 18 427 18 420 28 420 47 420 61 426 84 438 115 478 224 498 296 498 333 498 403 451 442 381 442 322 442 271 416 230 363 222 407 187 442 136 442 80 442 58 390 44 345 34 313 29 294 29 287 29 278 34 273 45 273 50 273 53 274 56 276 61 285 64 292 65 299 83 375 106 413 133 413 151 413 160 399 160 371 160 358 155 331 144 290L87 63C84 50 78 24 78 19 78-1 89-11 111-11 130-11 144-1 151 19 153 24 159 49 170 92L191 181 221 295C232 318 249 341 270 365 299 397 335 413 378 413 411 413 427 391 427 348 427 310 406 234 363 120 356 102 353 87 353 74 353 25 390-11 438-11 482-11 517 14 542 64 561 104 571 131 571 144 571 153 566 158 555 158 552 158 537 149 537 137Z"></path></g></g></g></g></svg></mjx-container> ,然后对每个<mjx-container class="MathJax" jax="SVG" overflow="overflow"><svg style="vertical-align:-.357ex" xmlns="http://www.w3.org/2000/svg" width="2.437ex" height="1.977ex" role="img" focusable="false" viewBox="0 -716 1077 873.8"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(1,-1)"><g data-mml-node="math" data-latex="A_i"><g data-mml-node="msub" data-latex="A_i"><g data-mml-node="mi" data-latex="A"><path data-c="1D434" d="M137 3C155 3 217 0 236 0 251 0 258 8 258 23 258 32 252 38 239 39 210 40 196 50 196 69 196 78 205 98 224 128 251 173 270 206 283 228L526 228C526 221 527 207 530 185 537 112 541 72 541 67 541 48 519 39 474 39 455 39 446 31 446 15 446 5 452 0 464 0 488 0 564 3 588 3 608 3 679 0 699 0 714 0 721 8 721 24 721 34 712 39 694 39 666 39 649 41 644 44 639 47 635 56 634 71L574 689C571 708 572 716 551 716 539 716 529 710 522 697L178 120C148 70 108 43 59 39 43 38 35 30 35 15 35 5 41 0 52 0 68 0 121 3 137 3M492 577 522 267 307 267Z"></path></g><g data-mml-node="mi" transform="translate(783,-150) scale(0.707)" data-latex="i"><path data-c="1D456" d="M284 621C284 648 271 661 244 661 216 661 188 633 188 605 188 578 202 565 229 565 257 565 284 593 284 621M259 138C237 59 205 19 164 19 151 19 144 28 144 47 144 64 173 150 232 306 240 329 244 347 244 360 244 409 210 445 161 445 118 445 84 420 59 369 39 328 29 301 29 288 29 279 34 275 45 275 58 275 60 281 64 295 87 375 118 415 158 415 171 415 178 406 178 387 178 373 175 357 168 338 145 275 121 208 101 155 86 115 78 88 78 74 78 25 114-11 162-11 205-11 239 14 264 64 283 103 293 130 293 145 293 154 288 159 277 159 274 159 259 150 259 138Z"></path></g></g></g></g></svg></mjx-container> 运用刚体变换(旋转和平移)进行重新排列,最终可以组合成两个单位球。特别地,这里构造的每一个<mjx-container class="MathJax" jax="SVG" overflow="overflow"><svg style="vertical-align:-.357ex" xmlns="http://www.w3.org/2000/svg" width="2.437ex" height="1.977ex" role="img" focusable="false" viewBox="0 -716 1077 873.8"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(1,-1)"><g data-mml-node="math" data-latex="A_i"><g data-mml-node="msub" data-latex="A_i"><g data-mml-node="mi" data-latex="A"><path data-c="1D434" d="M137 3C155 3 217 0 236 0 251 0 258 8 258 23 258 32 252 38 239 39 210 40 196 50 196 69 196 78 205 98 224 128 251 173 270 206 283 228L526 228C526 221 527 207 530 185 537 112 541 72 541 67 541 48 519 39 474 39 455 39 446 31 446 15 446 5 452 0 464 0 488 0 564 3 588 3 608 3 679 0 699 0 714 0 721 8 721 24 721 34 712 39 694 39 666 39 649 41 644 44 639 47 635 56 634 71L574 689C571 708 572 716 551 716 539 716 529 710 522 697L178 120C148 70 108 43 59 39 43 38 35 30 35 15 35 5 41 0 52 0 68 0 121 3 137 3M492 577 522 267 307 267Z"></path></g><g data-mml-node="mi" transform="translate(783,-150) scale(0.707)" data-latex="i"><path data-c="1D456" d="M284 621C284 648 271 661 244 661 216 661 188 633 188 605 188 578 202 565 229 565 257 565 284 593 284 621M259 138C237 59 205 19 164 19 151 19 144 28 144 47 144 64 173 150 232 306 240 329 244 347 244 360 244 409 210 445 161 445 118 445 84 420 59 369 39 328 29 301 29 288 29 279 34 275 45 275 58 275 60 281 64 295 87 375 118 415 158 415 171 415 178 406 178 387 178 373 175 357 168 338 145 275 121 208 101 155 86 115 78 88 78 74 78 25 114-11 162-11 205-11 239 14 264 64 283 103 293 130 293 145 293 154 288 159 277 159 274 159 259 150 259 138Z"></path></g></g></g></g></svg></mjx-container> 都是根据选择公理构造的不可测集。</p><p>巴拿赫 - 塔斯基 “悖论”:一个球可以分解和重新组合成两个大小和原来一样的球。</p><p>具体来说,我们选取一个由 2 个生成元生成的 “自由群”(free groups),并取一个十分特殊的分割(decomposition)。</p><p>我们将这个自由群对应于三维空间中有 2 个生成元的旋转群,然后通过选择公理,利用群的特殊分割对单位球进行分割。最终通过这一技巧得到这些不可测集经过重新组合后得到两个单位球。</p><p>上述技巧和悖论对于三维以上的情形都成立。但对于欧几里得平面(或者说圆盘)不成立。</p><p>von Neumann 在研究这个悖论时,提出了可均群(Amenable group)的概念,他发现三维以上情形之所以产生悖论,和这些空间的旋转群的非可均性(non-amenable)有关。</p><p>而对于圆盘的情形,在 1929 年,von Neumann 以有限块方式将圆盘分割后(成有限个不可测集),再用保面积的仿射变换(affine transformation)(不仅仅是平移或旋转)将这些不可测碎块重新组合成两个圆盘。</p><p>这主要基于在仿射变换群中寻找自由群的技巧。这一结果被称为冯・诺伊曼悖论(von Neumann paradox)。</p><h3 id="三、证明论(Proof-theory)"><a href="#三、证明论(Proof-theory)" class="headerlink" title="三、证明论(Proof theory)"></a>三、证明论(Proof theory)</h3><p>1927 年,von Neumann 在哥廷根已开始参与有关 “皮亚诺公理(Peano axioms)是否可推出初等算术” 的讨论(whether elementary arithmetic followed from Peano axioms)。</p><p>他在 Ackermann 的工作基础上,试图运用希尔伯特学派的 “有限主义(finistic)” 方法证明所谓的一阶算术的一致性(consistency of first-order arithmetic)。利用这一思想,他可以得到一部分的关于自然数算术的一致性。</p><p>1927 年后,von Neumann 仍然在试图利用证明论(proof theory)的方法来证明经典数学体系的一致性。</p><p>然而 1930 年 9 月,在第二届精确科学认识论会议(Second Conference on the Epistemology of the Exact Sciences)上,哥德尔(Kurt Friedrich Gödel, 1906-1978)公布了他的第一不完全性定理(First theorem of incompleteness)。</p><p>在此次会议上,von Neumann 建议 Gödel 将这一结果应用于 “不可判定的整数命题”(undecidable propositions about integers)。</p><p>不到一个月后,von Neumann 便致函 Gödel,指出了他定理的一个重要推论:一般的公理系统无法证明自身的一致性(the usual axiomatic systems are unable to demonstrate their own consistency)。</p><p>Gödel 回信称,他早已意识到这一结果(即后来称为 “第二不完全性定理”),并表示会寄去包含这两个定理的文章预印本,但最终并未发生。</p><p>von Neumann 在后续信件中明确承认了 Gödel 的优先发现权。</p><p>The first incompleteness theorem states that no consistent system of axioms whose theorems can be listed by an effective procedure (i.e. an algorithm) is capable of proving all truths about the arithmetic of natural numbers. For any such consistent formal system, there will always be statements about natural numbers that are true, but that are unprovable within the system.</p><p>First theorem of incompleteness</p><p>不过 von Neumann 的证明方法与 Gödel 的并不相同,而且他认为第二不完全性定理对希尔伯特纲领造成了比 Gödel 设想的更严重的打击。</p><p>这项发现对 von Neumann 的数学严谨观造成了巨大冲击,他也因此停止了在数学基础与元数学(metamathematics)方向上的继续研究。</p><p>The second incompleteness theorem, an extension of the first, shows that the system cannot demonstrate its own consistency.</p><p>Second theorem of incompleteness</p><h3 id="四、遍历理论(Ergodic-theory)"><a href="#四、遍历理论(Ergodic-theory)" class="headerlink" title="四、遍历理论(Ergodic theory)"></a>四、遍历理论(Ergodic theory)</h3><p>1932 年,von Neumann 发表的一系列论文在遍历理论这一数学分支奠定了重要基础。遍历理论是数学的一个分支,研究确定性动力系统(deterministic dynamical systems)的统计性质;它是对遍历性的研究。</p><p>这里,“统计性质” 指的是通过沿着动力系统轨迹的各种函数的时间平均行为来表达的性质。</p><p>von Neumann 的遍历定理(Von Neumann’s ergodic theorem)指出,对于一个单参数酉群(one-parameter unitary group)<mjx-container class="MathJax" jax="SVG" overflow="overflow"><svg style="vertical-align:-.566ex" xmlns="http://www.w3.org/2000/svg" width="0.817ex" height="2.262ex" role="img" focusable="false" viewBox="0 -750 361 1000"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(1,-1)"><g data-mml-node="math" data-latex="t \mapsto V_t"><g data-mml-node="mi" data-latex="t"><path data-c="1D461" d="M330 419C330 428 320 433 299 433L218 433C244 537 257 591 257 595 257 616 246 626 225 626 202 626 188 613 182 587L145 433 56 433C34 433 23 432 23 411 23 400 33 395 54 395L135 395C86 200 62 97 62 84 62 28 100-11 156-11 194-11 227 6 256 41 280 70 297 98 308 125 312 136 314 142 314 145 314 154 309 159 299 159 291 159 285 154 281 143 247 60 206 19 157 19 140 19 131 33 131 60 131 75 133 91 137 107L208 395 297 395C323 395 330 397 330 419Z"></path></g></g></g></svg><mjx-break size="4"></mjx-break><svg style="vertical-align:-.566ex" xmlns="http://www.w3.org/2000/svg" width="4.923ex" height="2.262ex" role="img" focusable="false" viewBox="0 -750 2176 1000"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(1,-1)"><g data-mml-node="math" data-latex="t \mapsto V_t"><g data-mml-node="mo" data-latex="\mapsto"><path data-c="21A6" d="M910 234C917 237 921 243 921 250 921 257 917 263 910 266 862 282 817 316 775 368 747 403 728 444 719 491 716 504 708 510 695 510 679 510 671 502 671 485L672 483 672 482C689 395 733 326 806 274L104 274 104 486C104 502 96 510 80 510 64 510 56 502 56 486L56 14C56-3 64-11 80-11 96-11 104-3 104 14L104 226 806 226C733 174 689 105 672 18L672 17 671 15C671-2 679-10 695-10 708-10 716-4 719 9 728 56 747 97 775 132 817 184 862 218 910 234Z"></path></g><g data-mml-node="msub" data-latex="V_t" transform="translate(1254.8,0)"><g data-mml-node="mi" data-latex="V"><path data-c="1D449" d="M671 680C652 680 592 683 573 683 558 683 550 675 550 660 550 650 557 645 570 644 598 643 612 633 612 616 612 607 607 595 598 580L300 107 234 619C234 636 255 644 298 644 318 644 327 651 327 668 327 678 321 683 309 683 287 683 209 680 187 680 167 680 99 683 79 683 64 683 56 675 56 660 56 649 66 644 85 644 102 644 114 642 122 640 138 635 137 633 140 614L218 4C221-13 229-22 242-22 255-22 265-15 273-2L629 564C652 600 674 623 696 632 711 639 730 643 752 644 763 645 768 652 769 667 770 678 764 683 752 683 737 683 686 680 671 680Z"></path></g><g data-mml-node="mi" transform="translate(616,-150) scale(0.707)" data-latex="t"><path data-c="1D461" d="M330 419C330 428 320 433 299 433L218 433C244 537 257 591 257 595 257 616 246 626 225 626 202 626 188 613 182 587L145 433 56 433C34 433 23 432 23 411 23 400 33 395 54 395L135 395C86 200 62 97 62 84 62 28 100-11 156-11 194-11 227 6 256 41 280 70 297 98 308 125 312 136 314 142 314 145 314 154 309 159 299 159 291 159 285 154 281 143 247 60 206 19 157 19 140 19 131 33 131 60 131 75 133 91 137 107L208 395 297 395C323 395 330 397 330 419Z"></path></g></g></g></g></svg></mjx-container> 作用在一个希尔伯特空间<mjx-container class="MathJax" jax="SVG" overflow="overflow"><svg style="vertical-align:0" xmlns="http://www.w3.org/2000/svg" width="1.993ex" height="1.545ex" role="img" focusable="false" viewBox="0 -683 881 683"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(1,-1)"><g data-mml-node="math" data-latex="H"><g data-mml-node="mi" data-latex="H"><path data-c="1D43B" d="M881 668C881 678 875 683 863 683L736 680 609 683C593 683 586 674 586 659 586 652 589 647 594 646 604 645 612 644 617 644 648 643 665 641 670 640 675 639 678 636 678 631 677 628 676 622 674 613L615 375 321 375 379 602C384 623 393 636 406 641 413 643 430 644 458 644 485 644 496 644 496 668 496 678 490 683 478 683L351 680 223 683C207 683 200 674 200 659 200 652 203 647 209 646 219 645 227 644 232 644 263 643 281 641 286 640 291 639 293 636 293 631 293 629 292 623 289 613L156 82C151 60 141 47 126 42 119 40 101 39 70 39 48 39 39 37 39 15 39 5 45 0 57 0L183 3 246 2C257 2 299 0 310 0 326 0 334 8 334 24 334 34 323 39 302 39 262 39 242 43 242 52 242 52 243 55 245 68L312 336 605 336 538 68C535 53 523 43 503 40 498 39 481 39 452 39 433 39 424 31 424 15 424 5 430 0 442 0L568 3 631 2C642 2 683 0 696 0 712 0 720 8 720 24 720 34 709 39 688 39 647 39 627 43 627 52 627 52 628 55 630 68L764 602C769 623 778 636 791 641 797 643 814 644 843 644 869 644 881 644 881 668Z"></path></g></g></g></svg></mjx-container> 上,对于希尔伯特空间<mjx-container class="MathJax" jax="SVG" overflow="overflow"><svg style="vertical-align:0" xmlns="http://www.w3.org/2000/svg" width="1.993ex" height="1.545ex" role="img" focusable="false" viewBox="0 -683 881 683"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(1,-1)"><g data-mml-node="math" data-latex="H"><g data-mml-node="mi" data-latex="H"><path data-c="1D43B" d="M881 668C881 678 875 683 863 683L736 680 609 683C593 683 586 674 586 659 586 652 589 647 594 646 604 645 612 644 617 644 648 643 665 641 670 640 675 639 678 636 678 631 677 628 676 622 674 613L615 375 321 375 379 602C384 623 393 636 406 641 413 643 430 644 458 644 485 644 496 644 496 668 496 678 490 683 478 683L351 680 223 683C207 683 200 674 200 659 200 652 203 647 209 646 219 645 227 644 232 644 263 643 281 641 286 640 291 639 293 636 293 631 293 629 292 623 289 613L156 82C151 60 141 47 126 42 119 40 101 39 70 39 48 39 39 37 39 15 39 5 45 0 57 0L183 3 246 2C257 2 299 0 310 0 326 0 334 8 334 24 334 34 323 39 302 39 262 39 242 43 242 52 242 52 243 55 245 68L312 336 605 336 538 68C535 53 523 43 503 40 498 39 481 39 452 39 433 39 424 31 424 15 424 5 430 0 442 0L568 3 631 2C642 2 683 0 696 0 712 0 720 8 720 24 720 34 709 39 688 39 647 39 627 43 627 52 627 52 628 55 630 68L764 602C769 623 778 636 791 641 797 643 814 644 843 644 869 644 881 644 881 668Z"></path></g></g></g></svg></mjx-container> 中的任意向量<mjx-container class="MathJax" jax="SVG" overflow="overflow"><svg style="vertical-align:-.464ex" xmlns="http://www.w3.org/2000/svg" width="1.348ex" height="2.034ex" role="img" focusable="false" viewBox="0 -694 596 899"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(1,-1)"><g data-mml-node="math" data-latex="\phi"><g data-mml-node="mi" data-latex="\phi"><path data-c="1D719" d="M385 445C404 524 424 601 442 680L442 683C439 690 434 694 426 694 417 694 411 686 408 671L351 445C276 442 208 414 147 362 82 307 49 243 49 170 49 62 132-7 237-13 218-92 204-149 195-183 194-186 194-189 194-190 194-200 199-205 210-205 221-205 224-199 227-187L271-14C346-11 414 17 475 69 540 125 573 189 573 262 573 369 488 436 385 445M377 415C453 410 501 363 501 283 501 243 492 203 474 164 442 92 369 26 278 17M121 149C121 189 130 229 148 268 180 340 253 405 343 415L244 16C169 22 121 69 121 149Z"></path></g></g></g></svg></mjx-container> ,极限</p><p><mjx-container class="MathJax" jax="SVG" overflow="overflow" display="true" width="full" style="min-width:28.359ex"><svg style="vertical-align:-2.238ex;min-width:28.359ex" xmlns="http://www.w3.org/2000/svg" width="100%" height="5.608ex" role="img" focusable="false"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(0.0181,-0.0181) translate(0, -1489.3)"><g data-mml-node="math" data-latex="
\lim_{T \to \infty} \frac{1}{T} \int_{0}^{T} V_t(\phi) dt
"><g data-mml-node="mtable" data-latex="
\lim_{T \to \infty} \frac{1}{T} \int_{0}^{T} V_t(\phi) dt
" transform="translate(2078,0) translate(-2078,0)"><g transform="translate(0 1489.3) matrix(1 0 0 -1 0 0) scale(55.25)"><svg data-table="true" preserveAspectRatio="xMidYMid" viewBox="4189.3 -1489.3 1 2478.7"><g transform="matrix(1 0 0 -1 0 0)"><g data-mml-node="mlabeledtr" transform="translate(0,-77.4)"><g data-mml-node="mtd"><g data-mml-node="munder" data-latex="\lim_{T\to\infty}"><g data-mml-node="mo" data-latex="\lim" transform="translate(261.5,0)"><path data-c="6C" d="M144 3 255 0 255 39C219 39 197 40 190 44 183 48 180 60 180 79L180 694 33 683 33 645C68 645 90 642 97 636 104 630 108 616 108 593L108 79C108 60 105 48 98 44 91 40 69 39 33 39L33 0Z"></path><path data-c="69" d="M194 601C194 631 169 657 139 657 109 657 83 631 83 601 83 571 108 544 138 544 169 544 194 570 194 601M143 3 247 0 247 39C214 39 194 41 188 45 182 49 180 60 180 78L180 445 37 433 37 395C70 395 91 392 98 387 105 382 108 368 108 345L108 79C108 60 105 48 98 44 91 40 69 39 33 39L33 0Z" transform="translate(278,0)"></path><path data-c="6D" d="M315 413C361 413 384 378 384 307L384 79C384 60 381 48 374 44 367 40 344 38 307 38L307 0 423 3 538 0 538 38C501 38 479 40 472 44 465 48 461 60 461 79L461 259C461 339 513 413 590 413 637 413 660 378 660 307L660 79C660 60 656 48 649 44 642 40 619 38 582 38L582 0 698 3 813 0 813 38C781 38 760 39 750 42 740 45 736 52 736 64L736 251C736 298 734 331 731 350 721 411 676 442 597 442 534 442 487 413 455 354 441 413 397 442 322 442 259 442 211 412 179 352L179 442 32 431 32 393C68 393 90 390 98 384 106 378 109 365 109 342L109 79C109 60 105 48 98 44 91 40 69 38 32 38L32 0 148 3 263 0 263 38C226 38 203 40 196 44 189 48 185 60 185 79L185 259C185 340 238 413 315 413Z" transform="translate(556,0)"></path></g><g data-mml-node="TeXAtom" transform="translate(0,-645.7) scale(0.707)" data-latex="{T\to\infty}" data-mjx-texclass="ORD"><g data-mml-node="mi" data-latex="T"><path data-c="1D447" d="M344 631C344 628 343 621 340 611L208 83C204 68 200 59 197 55 188 44 154 39 94 39 63 39 49 42 49 16 49 5 56 0 69 0 120 0 192 4 235 3L317 2C331 2 386 0 403 0 420 0 428 8 428 24 428 34 416 39 391 39 339 39 309 41 300 46 297 48 295 52 295 58L430 603C433 617 436 626 439 629 443 635 467 638 511 638 566 638 604 634 623 625 642 616 652 595 652 561 652 543 649 517 644 483 642 475 641 469 641 464 641 453 646 447 657 447 666 447 672 456 675 473L702 645C703 650 704 656 704 662 704 672 694 677 673 677L125 677C99 677 97 674 89 655L30 481C27 472 25 466 24 462 24 452 29 447 40 447 48 447 55 455 60 470 85 543 110 588 133 607 159 628 209 638 282 638L321 638C332 638 344 639 344 631Z"></path></g><g data-mml-node="mo" data-latex="\to" transform="translate(704,0)"><path data-c="2192" d="M932 234C939 237 943 243 943 250 943 257 939 263 932 266 884 282 839 316 797 368 769 403 750 444 741 491 738 504 730 510 717 510 701 510 693 502 693 485L694 483 694 482C711 395 755 326 828 274L82 274C66 274 58 266 58 250 58 234 66 226 82 226L828 226C755 174 711 105 694 18L694 17 693 15C693-2 701-10 717-10 730-10 738-4 741 9 750 56 769 97 797 132 839 184 884 218 932 234Z"></path></g><g data-mml-node="mi" data-latex="\infty" transform="translate(1704,0)"><path data-c="221E" d="M749-11C807-11 855 13 892 60 926 104 943 156 943 216 943 275 926 327 893 371 856 418 809 442 752 442 684 442 625 416 576 364 547 332 524 303 507 278 464 329 435 361 421 373 367 419 310 442 250 442 192 442 144 418 107 371 73 327 56 275 56 215 56 156 73 104 106 60 143 13 190-11 247-11 315-11 374 15 423 67 452 99 475 128 492 153 535 102 564 70 578 58 632 12 689-11 749-11M913 216C913 188 911 168 908 156 903 137 890 117 869 94 840 61 805 44 765 44 722 44 680 67 637 113 592 168 559 209 538 237 601 348 675 403 759 403 852 403 913 314 913 216M86 215C86 260 100 299 128 334 156 369 191 387 234 387 277 387 319 364 362 318 407 263 440 222 461 194 398 83 324 28 240 28 147 28 86 117 86 215Z"></path></g></g></g><g data-mml-node="mfrac" data-latex="\frac{1}{T}" transform="translate(2078.7,0)"><g data-mml-node="mn" data-latex="1" transform="translate(322,676)"><path data-c="31" d="M269 666C228 624 168 603 89 603L89 564C141 564 184 572 217 588L217 82C217 64 213 52 204 47 195 42 170 39 130 39L95 39 95 0C120 2 174 3 257 3 340 3 394 2 419 0L419 39 384 39C343 39 318 42 310 47 302 52 297 64 297 82L297 636C297 660 295 666 269 666Z"></path></g><g data-mml-node="mi" data-latex="T" transform="translate(220,-686)"><path data-c="1D447" d="M344 631C344 628 343 621 340 611L208 83C204 68 200 59 197 55 188 44 154 39 94 39 63 39 49 42 49 16 49 5 56 0 69 0 120 0 192 4 235 3L317 2C331 2 386 0 403 0 420 0 428 8 428 24 428 34 416 39 391 39 339 39 309 41 300 46 297 48 295 52 295 58L430 603C433 617 436 626 439 629 443 635 467 638 511 638 566 638 604 634 623 625 642 616 652 595 652 561 652 543 649 517 644 483 642 475 641 469 641 464 641 453 646 447 657 447 666 447 672 456 675 473L702 645C703 650 704 656 704 662 704 672 694 677 673 677L125 677C99 677 97 674 89 655L30 481C27 472 25 466 24 462 24 452 29 447 40 447 48 447 55 455 60 470 85 543 110 588 133 607 159 628 209 638 282 638L321 638C332 638 344 639 344 631Z"></path></g><rect width="904" height="60" x="120" y="220"></rect></g><g data-mml-node="msubsup" data-latex="\int_{0}^{T}" transform="translate(3389.4,0)"><g data-mml-node="mo" data-latex="\int"><path data-c="222B" d="M831 1361C784 1361 742 1318 703 1232 684 1191 664 1129 642 1046 545 688 472 339 395-117 360-328 331-481 308-574 267-745 220-831 168-831 149-831 132-826 117-815 146-810 160-793 160-763 160-734 138-711 109-711 74-711 56-729 56-764 56-822 113-861 170-861 243-861 303-803 350-688 375-627 409-509 451-336 524-39 589 279 646 617 686 854 722 1034 753 1157 782 1273 809 1331 833 1331 853 1331 870 1326 883 1315 854 1310 839 1293 839 1263 839 1234 861 1211 890 1211 925 1211 943 1229 943 1264 943 1319 889 1361 831 1361Z"></path></g><g data-mml-node="TeXAtom" transform="translate(1098.5,1088.1) scale(0.707)" data-latex="{T}" data-mjx-texclass="ORD"><g data-mml-node="mi" data-latex="T"><path data-c="1D447" d="M344 631C344 628 343 621 340 611L208 83C204 68 200 59 197 55 188 44 154 39 94 39 63 39 49 42 49 16 49 5 56 0 69 0 120 0 192 4 235 3L317 2C331 2 386 0 403 0 420 0 428 8 428 24 428 34 416 39 391 39 339 39 309 41 300 46 297 48 295 52 295 58L430 603C433 617 436 626 439 629 443 635 467 638 511 638 566 638 604 634 623 625 642 616 652 595 652 561 652 543 649 517 644 483 642 475 641 469 641 464 641 453 646 447 657 447 666 447 672 456 675 473L702 645C703 650 704 656 704 662 704 672 694 677 673 677L125 677C99 677 97 674 89 655L30 481C27 472 25 466 24 462 24 452 29 447 40 447 48 447 55 455 60 470 85 543 110 588 133 607 159 628 209 638 282 638L321 638C332 638 344 639 344 631Z"></path></g></g><g data-mml-node="TeXAtom" transform="translate(702,-896.4) scale(0.707)" data-latex="{0}" data-mjx-texclass="ORD"><g data-mml-node="mn" data-latex="0"><path data-c="30" d="M249-22C390-22 460 92 460 320 460 473 428 575 365 625 330 652 291 666 250 666 109 666 39 551 39 320 39 136 88-22 249-22M361 524C368 489 371 425 371 332 371 240 367 172 360 128 347 48 310 8 249 8 226 8 203 17 182 34 155 57 139 104 132 176 129 201 128 253 128 332 128 419 131 480 136 513 145 568 163 603 191 618 213 630 232 636 249 636 314 636 350 583 361 524Z"></path></g></g></g><g data-mml-node="msub" data-latex="V_t" transform="translate(5202.3,0)"><g data-mml-node="mi" data-latex="V"><path data-c="1D449" d="M671 680C652 680 592 683 573 683 558 683 550 675 550 660 550 650 557 645 570 644 598 643 612 633 612 616 612 607 607 595 598 580L300 107 234 619C234 636 255 644 298 644 318 644 327 651 327 668 327 678 321 683 309 683 287 683 209 680 187 680 167 680 99 683 79 683 64 683 56 675 56 660 56 649 66 644 85 644 102 644 114 642 122 640 138 635 137 633 140 614L218 4C221-13 229-22 242-22 255-22 265-15 273-2L629 564C652 600 674 623 696 632 711 639 730 643 752 644 763 645 768 652 769 667 770 678 764 683 752 683 737 683 686 680 671 680Z"></path></g><g data-mml-node="mi" transform="translate(616,-150) scale(0.707)" data-latex="t"><path data-c="1D461" d="M330 419C330 428 320 433 299 433L218 433C244 537 257 591 257 595 257 616 246 626 225 626 202 626 188 613 182 587L145 433 56 433C34 433 23 432 23 411 23 400 33 395 54 395L135 395C86 200 62 97 62 84 62 28 100-11 156-11 194-11 227 6 256 41 280 70 297 98 308 125 312 136 314 142 314 145 314 154 309 159 299 159 291 159 285 154 281 143 247 60 206 19 157 19 140 19 131 33 131 60 131 75 133 91 137 107L208 395 297 395C323 395 330 397 330 419Z"></path></g></g><g data-mml-node="mo" data-latex="(" transform="translate(6123.6,0)"><path data-c="28" d="M318-248C327-248 332-243 332-234 332-231 330-227 327-223 275-183 233-117 202-26 175 53 161 131 161 208L161 292C161 369 175 447 202 526 233 617 275 683 327 723 330 726 332 730 332 734 332 743 327 748 318 748 317 748 314 747 311 745 251 699 201 631 160 540 121 453 101 371 101 292L101 208C101 129 121 47 160-40 201-131 251-199 311-245 314-247 317-248 318-248Z"></path></g><g data-mml-node="mi" data-latex="\phi" transform="translate(6512.6,0)"><path data-c="1D719" d="M385 445C404 524 424 601 442 680L442 683C439 690 434 694 426 694 417 694 411 686 408 671L351 445C276 442 208 414 147 362 82 307 49 243 49 170 49 62 132-7 237-13 218-92 204-149 195-183 194-186 194-189 194-190 194-200 199-205 210-205 221-205 224-199 227-187L271-14C346-11 414 17 475 69 540 125 573 189 573 262 573 369 488 436 385 445M377 415C453 410 501 363 501 283 501 243 492 203 474 164 442 92 369 26 278 17M121 149C121 189 130 229 148 268 180 340 253 405 343 415L244 16C169 22 121 69 121 149Z"></path></g><g data-mml-node="mo" data-latex=")" transform="translate(7108.6,0)"><path data-c="29" d="M78-245C138-199 188-131 229-40 268 47 288 129 288 208L288 292C288 371 268 453 229 540 188 631 138 699 78 745 75 747 72 748 71 748 62 748 57 743 57 734 57 730 59 726 62 723 114 683 156 617 187 526 214 447 228 369 228 292L228 208C228 131 214 53 187-26 156-117 114-183 62-223 59-227 57-231 57-234 57-243 62-248 71-248 72-248 75-247 78-245Z"></path></g><g data-mml-node="mi" data-latex="d" transform="translate(7497.6,0)"><path data-c="1D451" d="M429 632 370 389C349 426 320 445 281 445 216 445 159 412 109 345 63 283 40 218 40 151 40 63 91-11 175-11 218-11 260 12 300 59 311 21 345-11 392-11 461-11 483 71 498 145 498 154 493 159 483 159 474 159 468 152 465 138 445 59 421 19 394 19 377 19 368 33 368 60 368 75 370 91 374 107L516 679 516 683C513 690 507 694 499 694 476 694 434 690 374 683 363 682 357 674 357 660 357 650 366 645 384 645 403 645 429 646 429 632M341 376C351 355 356 341 356 332 355 328 354 323 353 316L304 122C301 111 294 99 285 87 248 42 212 19 177 19 138 19 118 49 118 108 118 132 124 168 136 216 157 301 187 359 224 390 244 407 263 415 282 415 309 415 329 402 341 376Z"></path></g><g data-mml-node="mi" data-latex="t" transform="translate(8017.6,0)"><path data-c="1D461" d="M330 419C330 428 320 433 299 433L218 433C244 537 257 591 257 595 257 616 246 626 225 626 202 626 188 613 182 587L145 433 56 433C34 433 23 432 23 411 23 400 33 395 54 395L135 395C86 200 62 97 62 84 62 28 100-11 156-11 194-11 227 6 256 41 280 70 297 98 308 125 312 136 314 142 314 145 314 154 309 159 299 159 291 159 285 154 281 143 247 60 206 19 157 19 140 19 131 33 131 60 131 75 133 91 137 107L208 395 297 395C323 395 330 397 330 419Z"></path></g></g></g></g></svg><svg data-labels="true" preserveAspectRatio="xMaxYMid" viewBox="1278 -1489.3 1 2478.7"><g data-labels="true" transform="matrix(1 0 0 -1 0 0)"><g data-mml-node="mtd" id="mjx-eqn:1" transform="translate(0,670.6)"><text data-id-align="true"></text><g data-idbox="true" transform="translate(0,-748)"><g data-mml-node="mtext" data-latex="\text{(1)}"><path data-c="28" d="M318-248C327-248 332-243 332-234 332-231 330-227 327-223 275-183 233-117 202-26 175 53 161 131 161 208L161 292C161 369 175 447 202 526 233 617 275 683 327 723 330 726 332 730 332 734 332 743 327 748 318 748 317 748 314 747 311 745 251 699 201 631 160 540 121 453 101 371 101 292L101 208C101 129 121 47 160-40 201-131 251-199 311-245 314-247 317-248 318-248Z"></path><path data-c="31" d="M269 666C228 624 168 603 89 603L89 564C141 564 184 572 217 588L217 82C217 64 213 52 204 47 195 42 170 39 130 39L95 39 95 0C120 2 174 3 257 3 340 3 394 2 419 0L419 39 384 39C343 39 318 42 310 47 302 52 297 64 297 82L297 636C297 660 295 666 269 666Z" transform="translate(389,0)"></path><path data-c="29" d="M78-245C138-199 188-131 229-40 268 47 288 129 288 208L288 292C288 371 268 453 229 540 188 631 138 699 78 745 75 747 72 748 71 748 62 748 57 743 57 734 57 730 59 726 62 723 114 683 156 617 187 526 214 447 228 369 228 292L228 208C228 131 214 53 187-26 156-117 114-183 62-223 59-227 57-231 57-234 57-243 62-248 71-248 72-248 75-247 78-245Z" transform="translate(889,0)"></path></g></g></g></g></svg></g></g></g></g></svg></mjx-container></p><p>在希尔伯特范数(Hilbert Norm)定义的度量意义下存在,且极限是一个向量<mjx-container class="MathJax" jax="SVG" overflow="overflow"><svg style="vertical-align:-.464ex" xmlns="http://www.w3.org/2000/svg" width="1.473ex" height="2.034ex" role="img" focusable="false" viewBox="0 -694 651 899"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(1,-1)"><g data-mml-node="math" data-latex="\psi"><g data-mml-node="mi" data-latex="\psi"><path data-c="1D713" d="M534 393C534 384 539 374 550 363 573 341 585 314 585 282 585 253 576 222 557 187 522 120 476 72 421 43 388 26 355 18 322 17L484 663C486 672 487 677 487 679 487 689 482 694 471 694 466 694 463 693 460 691 456 683 454 676 453 671L290 19C219 28 184 64 184 126 184 153 202 214 237 309 244 329 248 346 248 359 248 409 213 444 163 444 118 444 84 419 59 369 39 329 29 302 29 288 29 279 34 274 45 274 58 274 60 280 64 294 87 374 119 414 160 414 174 414 181 405 181 387 181 371 174 343 159 303 127 218 111 162 111 134 111 47 168-1 282-10 274-45 267-74 261-96 246-153 238-185 238-192 241-200 242-205 255-205L265-201C271-185 276-170 279-157L315-13C397-12 469 24 531 95 564 132 588 172 604 215 625 270 635 322 635 371 635 420 619 444 588 444 562 444 534 419 534 393Z"></path></g></g></g></svg></mjx-container> ,且对所有<mjx-container class="MathJax" jax="SVG" overflow="overflow"><svg style="vertical-align:-.025ex" xmlns="http://www.w3.org/2000/svg" width="0.817ex" height="1.441ex" role="img" focusable="false" viewBox="0 -626 361 637"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(1,-1)"><g data-mml-node="math" data-latex="t"><g data-mml-node="mi" data-latex="t"><path data-c="1D461" d="M330 419C330 428 320 433 299 433L218 433C244 537 257 591 257 595 257 616 246 626 225 626 202 626 188 613 182 587L145 433 56 433C34 433 23 432 23 411 23 400 33 395 54 395L135 395C86 200 62 97 62 84 62 28 100-11 156-11 194-11 227 6 256 41 280 70 297 98 308 125 312 136 314 142 314 145 314 154 309 159 299 159 291 159 285 154 281 143 247 60 206 19 157 19 140 19 131 33 131 60 131 75 133 91 137 107L208 395 297 395C323 395 330 397 330 419Z"></path></g></g></g></svg></mjx-container> 都满足<mjx-container class="MathJax" jax="SVG" overflow="overflow"><svg style="vertical-align:-.566ex" xmlns="http://www.w3.org/2000/svg" width="5.317ex" height="2.262ex" role="img" focusable="false" viewBox="0 -750 2350.3 1000"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(1,-1)"><g data-mml-node="math" data-latex="V_t(\psi) = \psi"><g data-mml-node="msub" data-latex="V_t"><g data-mml-node="mi" data-latex="V"><path data-c="1D449" d="M671 680C652 680 592 683 573 683 558 683 550 675 550 660 550 650 557 645 570 644 598 643 612 633 612 616 612 607 607 595 598 580L300 107 234 619C234 636 255 644 298 644 318 644 327 651 327 668 327 678 321 683 309 683 287 683 209 680 187 680 167 680 99 683 79 683 64 683 56 675 56 660 56 649 66 644 85 644 102 644 114 642 122 640 138 635 137 633 140 614L218 4C221-13 229-22 242-22 255-22 265-15 273-2L629 564C652 600 674 623 696 632 711 639 730 643 752 644 763 645 768 652 769 667 770 678 764 683 752 683 737 683 686 680 671 680Z"></path></g><g data-mml-node="mi" transform="translate(616,-150) scale(0.707)" data-latex="t"><path data-c="1D461" d="M330 419C330 428 320 433 299 433L218 433C244 537 257 591 257 595 257 616 246 626 225 626 202 626 188 613 182 587L145 433 56 433C34 433 23 432 23 411 23 400 33 395 54 395L135 395C86 200 62 97 62 84 62 28 100-11 156-11 194-11 227 6 256 41 280 70 297 98 308 125 312 136 314 142 314 145 314 154 309 159 299 159 291 159 285 154 281 143 247 60 206 19 157 19 140 19 131 33 131 60 131 75 133 91 137 107L208 395 297 395C323 395 330 397 330 419Z"></path></g></g><g data-mml-node="mo" data-latex="(" transform="translate(921.3,0)"><path data-c="28" d="M318-248C327-248 332-243 332-234 332-231 330-227 327-223 275-183 233-117 202-26 175 53 161 131 161 208L161 292C161 369 175 447 202 526 233 617 275 683 327 723 330 726 332 730 332 734 332 743 327 748 318 748 317 748 314 747 311 745 251 699 201 631 160 540 121 453 101 371 101 292L101 208C101 129 121 47 160-40 201-131 251-199 311-245 314-247 317-248 318-248Z"></path></g><g data-mml-node="mi" data-latex="\psi" transform="translate(1310.3,0)"><path data-c="1D713" d="M534 393C534 384 539 374 550 363 573 341 585 314 585 282 585 253 576 222 557 187 522 120 476 72 421 43 388 26 355 18 322 17L484 663C486 672 487 677 487 679 487 689 482 694 471 694 466 694 463 693 460 691 456 683 454 676 453 671L290 19C219 28 184 64 184 126 184 153 202 214 237 309 244 329 248 346 248 359 248 409 213 444 163 444 118 444 84 419 59 369 39 329 29 302 29 288 29 279 34 274 45 274 58 274 60 280 64 294 87 374 119 414 160 414 174 414 181 405 181 387 181 371 174 343 159 303 127 218 111 162 111 134 111 47 168-1 282-10 274-45 267-74 261-96 246-153 238-185 238-192 241-200 242-205 255-205L265-201C271-185 276-170 279-157L315-13C397-12 469 24 531 95 564 132 588 172 604 215 625 270 635 322 635 371 635 420 619 444 588 444 562 444 534 419 534 393Z"></path></g><g data-mml-node="mo" data-latex=")" transform="translate(1961.3,0)"><path data-c="29" d="M78-245C138-199 188-131 229-40 268 47 288 129 288 208L288 292C288 371 268 453 229 540 188 631 138 699 78 745 75 747 72 748 71 748 62 748 57 743 57 734 57 730 59 726 62 723 114 683 156 617 187 526 214 447 228 369 228 292L228 208C228 131 214 53 187-26 156-117 114-183 62-223 59-227 57-231 57-234 57-243 62-248 71-248 72-248 75-247 78-245Z"></path></g></g></g></svg><mjx-break size="4"></mjx-break><svg style="vertical-align:-.566ex" xmlns="http://www.w3.org/2000/svg" width="3.861ex" height="2.262ex" role="img" focusable="false" viewBox="0 -750 1706.8 1000"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(1,-1)"><g data-mml-node="math" data-latex="V_t(\psi) = \psi"><g data-mml-node="mo" data-latex="="><path data-c="3D" d="M698 367 80 367C64 367 56 359 56 344 56 329 64 321 80 321L698 321C714 321 722 329 722 344 722 356 711 367 698 367M698 179 80 179C64 179 56 171 56 156 56 141 64 133 80 133L698 133C714 133 722 141 722 156 722 169 711 179 698 179Z"></path></g><g data-mml-node="mi" data-latex="\psi" transform="translate(1055.8,0)"><path data-c="1D713" d="M534 393C534 384 539 374 550 363 573 341 585 314 585 282 585 253 576 222 557 187 522 120 476 72 421 43 388 26 355 18 322 17L484 663C486 672 487 677 487 679 487 689 482 694 471 694 466 694 463 693 460 691 456 683 454 676 453 671L290 19C219 28 184 64 184 126 184 153 202 214 237 309 244 329 248 346 248 359 248 409 213 444 163 444 118 444 84 419 59 369 39 329 29 302 29 288 29 279 34 274 45 274 58 274 60 280 64 294 87 374 119 414 160 414 174 414 181 405 181 387 181 371 174 343 159 303 127 218 111 162 111 134 111 47 168-1 282-10 274-45 267-74 261-96 246-153 238-185 238-192 241-200 242-205 255-205L265-201C271-185 276-170 279-157L315-13C397-12 469 24 531 95 564 132 588 172 604 215 625 270 635 322 635 371 635 420 619 444 588 444 562 444 534 419 534 393Z"></path></g></g></g></svg></mjx-container> 。</p><p>1932 年晚些时候,von Neumann 发表了另一篇具有影响力的论文,系统性地研究了遍历性。</p><p>他提出并证明了一个分解定理,表明对实数遍历的保持测度的作用(ergodic measure preserving actions of the real line)构成了构造任何测度保持作用(measure preserving actions)的基本元素(fundamental building blocks)。</p><p>他在这篇论文以及随后与哈尔莫斯(Paul Richard Halmos,1916-2006)合作的另一篇论文中得到的一系列关键定理,对数学其他领域也有重要应用。</p></div><div class="story post-story"><h2 id="五、测度论(Measure-theory)"><a href="#五、测度论(Measure-theory)" class="headerlink" title="五、测度论(Measure theory)"></a>五、测度论(Measure theory)</h2><p>在测度论中,有所谓的<mjx-container class="MathJax" jax="SVG" overflow="overflow"><svg style="vertical-align:-.025ex" xmlns="http://www.w3.org/2000/svg" width="1.357ex" height="1.025ex" role="img" focusable="false" viewBox="0 -442 600 453"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(1,-1)"><g data-mml-node="math" data-latex="n"><g data-mml-node="mi" data-latex="n"><path data-c="1D45B" d="M537 137C514 58 481 18 440 18 427 18 420 28 420 47 420 61 426 84 438 115 478 224 498 296 498 333 498 403 451 442 381 442 322 442 271 416 230 363 222 407 187 442 136 442 80 442 58 390 44 345 34 313 29 294 29 287 29 278 34 273 45 273 50 273 53 274 56 276 61 285 64 292 65 299 83 375 106 413 133 413 151 413 160 399 160 371 160 358 155 331 144 290L87 63C84 50 78 24 78 19 78-1 89-11 111-11 130-11 144-1 151 19 153 24 159 49 170 92L191 181 221 295C232 318 249 341 270 365 299 397 335 413 378 413 411 413 427 391 427 348 427 310 406 234 363 120 356 102 353 87 353 74 353 25 390-11 438-11 482-11 517 14 542 64 561 104 571 131 571 144 571 153 566 158 555 158 552 158 537 149 537 137Z"></path></g></g></g></svg></mjx-container> 维欧几里得空间<mjx-container class="MathJax" jax="SVG" overflow="overflow"><svg style="vertical-align:0" xmlns="http://www.w3.org/2000/svg" width="2.781ex" height="1.55ex" role="img" focusable="false" viewBox="0 -685 1229.3 685"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(1,-1)"><g data-mml-node="math" data-latex="\mathbb{R}^n"><g data-mml-node="msup" data-latex="\mathbb{R}^n"><g data-mml-node="TeXAtom" data-latex="\mathbb{R}" data-mjx-texclass="ORD"><g data-mml-node="mi" data-latex="R"><path data-c="211D" d="M104 590 104 95C104 45 99 43 47 43 26 43 16 36 16 22 16 4 31 0 54 0L324 0C349 0 361 7 361 22 361 36 350 43 329 43 277 43 273 45 273 95L273 310 302 310 450 83C475 43 490 20 494 14 500 5 512 0 530 0L666 0C691 0 703 7 703 22 703 33 697 40 685 42 660 47 625 82 579 146 534 208 494 267 459 322 573 344 630 402 630 496 630 563 600 613 540 644 488 671 429 685 364 685L54 685C29 685 16 678 16 663 16 649 26 642 47 642 99 642 104 640 104 590M535 597C570 576 587 542 587 496 587 427 547 385 468 368 485 396 494 438 494 495 494 552 483 596 462 629 487 622 512 612 535 597M452 495C452 433 441 394 419 378 397 362 348 353 273 353L273 593C273 630 287 642 330 642 425 642 452 595 452 495M413 316C496 184 561 93 610 43L525 43 352 311C357 312 361 312 364 312 378 312 394 313 413 316M140 642 240 642C234 631 231 616 231 596L231 93C231 72 233 55 237 43L140 43C144 55 146 72 146 93L146 592C146 613 144 630 140 642Z"></path></g></g><g data-mml-node="mi" transform="translate(755,363) scale(0.707)" data-latex="n"><path data-c="1D45B" d="M537 137C514 58 481 18 440 18 427 18 420 28 420 47 420 61 426 84 438 115 478 224 498 296 498 333 498 403 451 442 381 442 322 442 271 416 230 363 222 407 187 442 136 442 80 442 58 390 44 345 34 313 29 294 29 287 29 278 34 273 45 273 50 273 53 274 56 276 61 285 64 292 65 299 83 375 106 413 133 413 151 413 160 399 160 371 160 358 155 331 144 290L87 63C84 50 78 24 78 19 78-1 89-11 111-11 130-11 144-1 151 19 153 24 159 49 170 92L191 181 221 295C232 318 249 341 270 365 299 397 335 413 378 413 411 413 427 391 427 348 427 310 406 234 363 120 356 102 353 87 353 74 353 25 390-11 438-11 482-11 517 14 542 64 561 104 571 131 571 144 571 153 566 158 555 158 552 158 537 149 537 137Z"></path></g></g></g></g></svg></mjx-container> 的 “测度问题(problem of measure)”,可以表述为:在<mjx-container class="MathJax" jax="SVG" overflow="overflow"><svg style="vertical-align:0" xmlns="http://www.w3.org/2000/svg" width="2.781ex" height="1.55ex" role="img" focusable="false" viewBox="0 -685 1229.3 685"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(1,-1)"><g data-mml-node="math" data-latex="\mathbb{R}^n"><g data-mml-node="msup" data-latex="\mathbb{R}^n"><g data-mml-node="TeXAtom" data-latex="\mathbb{R}" data-mjx-texclass="ORD"><g data-mml-node="mi" data-latex="R"><path data-c="211D" d="M104 590 104 95C104 45 99 43 47 43 26 43 16 36 16 22 16 4 31 0 54 0L324 0C349 0 361 7 361 22 361 36 350 43 329 43 277 43 273 45 273 95L273 310 302 310 450 83C475 43 490 20 494 14 500 5 512 0 530 0L666 0C691 0 703 7 703 22 703 33 697 40 685 42 660 47 625 82 579 146 534 208 494 267 459 322 573 344 630 402 630 496 630 563 600 613 540 644 488 671 429 685 364 685L54 685C29 685 16 678 16 663 16 649 26 642 47 642 99 642 104 640 104 590M535 597C570 576 587 542 587 496 587 427 547 385 468 368 485 396 494 438 494 495 494 552 483 596 462 629 487 622 512 612 535 597M452 495C452 433 441 394 419 378 397 362 348 353 273 353L273 593C273 630 287 642 330 642 425 642 452 595 452 495M413 316C496 184 561 93 610 43L525 43 352 311C357 312 361 312 364 312 378 312 394 313 413 316M140 642 240 642C234 631 231 616 231 596L231 93C231 72 233 55 237 43L140 43C144 55 146 72 146 93L146 592C146 613 144 630 140 642Z"></path></g></g><g data-mml-node="mi" transform="translate(755,363) scale(0.707)" data-latex="n"><path data-c="1D45B" d="M537 137C514 58 481 18 440 18 427 18 420 28 420 47 420 61 426 84 438 115 478 224 498 296 498 333 498 403 451 442 381 442 322 442 271 416 230 363 222 407 187 442 136 442 80 442 58 390 44 345 34 313 29 294 29 287 29 278 34 273 45 273 50 273 53 274 56 276 61 285 64 292 65 299 83 375 106 413 133 413 151 413 160 399 160 371 160 358 155 331 144 290L87 63C84 50 78 24 78 19 78-1 89-11 111-11 130-11 144-1 151 19 153 24 159 49 170 92L191 181 221 295C232 318 249 341 270 365 299 397 335 413 378 413 411 413 427 391 427 348 427 310 406 234 363 120 356 102 353 87 353 74 353 25 390-11 438-11 482-11 517 14 542 64 561 104 571 131 571 144 571 153 566 158 555 158 552 158 537 149 537 137Z"></path></g></g></g></g></svg></mjx-container> 的所有子集所构成的类上,是否存在一个正的(positive)、归一化(normalized)、不变(invariant)且可加(additive)的集合函数(set function)?</p><p>在之前 Hausdorff 和 Banach 的工作表明<mjx-container class="MathJax" jax="SVG" overflow="overflow"><svg style="vertical-align:-.566ex" xmlns="http://www.w3.org/2000/svg" width="1.357ex" height="2.262ex" role="img" focusable="false" viewBox="0 -750 600 1000"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(1,-1)"><g data-mml-node="math" data-latex="n=1"><g data-mml-node="mi" data-latex="n"><path data-c="1D45B" d="M537 137C514 58 481 18 440 18 427 18 420 28 420 47 420 61 426 84 438 115 478 224 498 296 498 333 498 403 451 442 381 442 322 442 271 416 230 363 222 407 187 442 136 442 80 442 58 390 44 345 34 313 29 294 29 287 29 278 34 273 45 273 50 273 53 274 56 276 61 285 64 292 65 299 83 375 106 413 133 413 151 413 160 399 160 371 160 358 155 331 144 290L87 63C84 50 78 24 78 19 78-1 89-11 111-11 130-11 144-1 151 19 153 24 159 49 170 92L191 181 221 295C232 318 249 341 270 365 299 397 335 413 378 413 411 413 427 391 427 348 427 310 406 234 363 120 356 102 353 87 353 74 353 25 390-11 438-11 482-11 517 14 542 64 561 104 571 131 571 144 571 153 566 158 555 158 552 158 537 149 537 137Z"></path></g></g></g></svg><mjx-break size="4"></mjx-break><svg style="vertical-align:-.566ex" xmlns="http://www.w3.org/2000/svg" width="3.52ex" height="2.262ex" role="img" focusable="false" viewBox="0 -750 1555.8 1000"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(1,-1)"><g data-mml-node="math" data-latex="n=1"><g data-mml-node="mo" data-latex="="><path data-c="3D" d="M698 367 80 367C64 367 56 359 56 344 56 329 64 321 80 321L698 321C714 321 722 329 722 344 722 356 711 367 698 367M698 179 80 179C64 179 56 171 56 156 56 141 64 133 80 133L698 133C714 133 722 141 722 156 722 169 711 179 698 179Z"></path></g><g data-mml-node="mn" data-latex="1" transform="translate(1055.8,0)"><path data-c="31" d="M269 666C228 624 168 603 89 603L89 564C141 564 184 572 217 588L217 82C217 64 213 52 204 47 195 42 170 39 130 39L95 39 95 0C120 2 174 3 257 3 340 3 394 2 419 0L419 39 384 39C343 39 318 42 310 47 302 52 297 64 297 82L297 636C297 660 295 666 269 666Z"></path></g></g></g></svg></mjx-container>、<mjx-container class="MathJax" jax="SVG" overflow="overflow"><svg style="vertical-align:0" xmlns="http://www.w3.org/2000/svg" width="1.131ex" height="1.507ex" role="img" focusable="false" viewBox="0 -666 500 666"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(1,-1)"><g data-mml-node="math" data-latex="2"><g data-mml-node="mn" data-latex="2"><path data-c="32" d="M237 666C186 666 143 648 106 612 69 576 50 534 50 483 50 449 75 424 106 424 136 424 161 450 161 480 161 513 137 536 105 536 102 536 100 536 98 535 117 584 161 627 224 627 306 627 352 556 352 470 352 403 318 331 250 255L62 43C49 28 50 29 50 0L421 0 450 180 417 180C409 129 402 100 396 91 391 86 361 84 306 84L139 84 236 179C304 243 390 312 419 365 439 400 449 435 449 470 449 588 357 666 237 666Z"></path></g></g></g></svg></mjx-container> 时,上述问题的答案是存在。</p><p>而我们提到的 Banach-Tarski paradox 则表示上述问题在<mjx-container class="MathJax" jax="SVG" overflow="overflow"><svg style="vertical-align:-.566ex" xmlns="http://www.w3.org/2000/svg" width="1.357ex" height="2.262ex" role="img" focusable="false" viewBox="0 -750 600 1000"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(1,-1)"><g data-mml-node="math" data-latex="n>2"><g data-mml-node="mi" data-latex="n"><path data-c="1D45B" d="M537 137C514 58 481 18 440 18 427 18 420 28 420 47 420 61 426 84 438 115 478 224 498 296 498 333 498 403 451 442 381 442 322 442 271 416 230 363 222 407 187 442 136 442 80 442 58 390 44 345 34 313 29 294 29 287 29 278 34 273 45 273 50 273 53 274 56 276 61 285 64 292 65 299 83 375 106 413 133 413 151 413 160 399 160 371 160 358 155 331 144 290L87 63C84 50 78 24 78 19 78-1 89-11 111-11 130-11 144-1 151 19 153 24 159 49 170 92L191 181 221 295C232 318 249 341 270 365 299 397 335 413 378 413 411 413 427 391 427 348 427 310 406 234 363 120 356 102 353 87 353 74 353 25 390-11 438-11 482-11 517 14 542 64 561 104 571 131 571 144 571 153 566 158 555 158 552 158 537 149 537 137Z"></path></g></g></g></svg><mjx-break size="4"></mjx-break><svg style="vertical-align:-.566ex" xmlns="http://www.w3.org/2000/svg" width="3.52ex" height="2.262ex" role="img" focusable="false" viewBox="0 -750 1555.8 1000"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(1,-1)"><g data-mml-node="math" data-latex="n>2"><g data-mml-node="mo" data-latex=">"><path data-c="3E" d="M686 227C696 232 701 239 701 250 701 261 696 268 686 273L112 545C109 546 105 547 101 547 85 547 77 539 77 522 77 513 82 506 91 502L625 250 91-2C82-6 77-13 77-22 77-39 85-47 101-47 105-47 109-46 112-45Z"></path></g><g data-mml-node="mn" data-latex="2" transform="translate(1055.8,0)"><path data-c="32" d="M237 666C186 666 143 648 106 612 69 576 50 534 50 483 50 449 75 424 106 424 136 424 161 450 161 480 161 513 137 536 105 536 102 536 100 536 98 535 117 584 161 627 224 627 306 627 352 556 352 470 352 403 318 331 250 255L62 43C49 28 50 29 50 0L421 0 450 180 417 180C409 129 402 100 396 91 391 86 361 84 306 84L139 84 236 179C304 243 390 312 419 365 439 400 449 435 449 470 449 588 357 666 237 666Z"></path></g></g></g></svg></mjx-container> 时答案是不存在。</p><p>von Neumann 的工作指出,“该问题本质上是一个与群论相关的问题”:能否存在这样一个测度,可以通过考察给定空间的变换群的性质来决定。</p><p>对于维度不超过 2 的情形,欧几里得群(Euclidean group)是可解群(solvable group),故答案为肯定;而对于更高维的情形,该群不可解,因此答案是否定。</p><p>在 von Neumann 的多篇论文中,他所使用的论证方法往往比结论本身更为重要。</p><p>为了给后来在算子代数中研究维数理论打下基础,von Neumann 利用 “有限分解等价”(equivalence by finite decomposition)的研究成果,将测度问题用函数的观点加以重新表述。</p><p>此外,von Neumann 还回应了 Haar 提出的关于实数轴上有界函数代数的疑问:whether there existed an algebra of all bounded functions on the real number line such that they form “a complete system of representatives of the classes of almost everywhere-equal measurable bounded functions”.</p><p>证明了 “完备表示几乎处处相等可测有界函数类”("a complete system of representatives of the classes of almost everywhere-equal measurable bounded functions")的存在性,并与斯通(Marshall Harvey Stone, 1903-1989)合作深入讨论了其推广及代数意义。</p><p>他不仅在分析测度分解方面提出了新方法,也通过函数平均值给出了适用于紧群的 Haar 测度唯一性新论证。</p><p>他在普林斯顿高等研究院讲授的测度论课程,更成为当时美国学术界研究该领域的核心材料。</p><h3 id="六、拓扑群(Topological-groups)"><a href="#六、拓扑群(Topological-groups)" class="headerlink" title="六、拓扑群(Topological groups)"></a>六、拓扑群(Topological groups)</h3><p>利用此前在测度论方面的研究成果,von Neumann 在拓扑群理论上也作出了若干贡献。</p><p>其开端是一篇关于群上近周期函数(almost periodic functions)的论文,von Neumann 在其中将 Bohr 对近似周期函数的研究推广到任意群。</p><p>他随后与博赫纳(Salomon Bochner, 1899-1982)合作的另一篇论文,则将近似周期性的理论进一步扩展到可取线性空间元素为值的函数。</p><p>1923 | G. D. Birkhoff<br>1924 | Eric Temple Bell; S. Lefschetz<br>1928 | J. W. Alexander II<br>1933 | M. Morse; N. Wiener<br>1938 | John von Neumann<br>1943 | Jesse Douglas<br>1948 | Albert Schaeffer; Donald Spencer<br>1953 | Norman Levinson<br>1959 | Louis Nirenberg<br>1964 | Paul Cohen<br>1969 | Isadore Singer<br>1974 | D. S. Ornstein<br>1979 | A. Calderón<br>1984 | Luis Caffarelli; Richard Melrose<br>1989 | Richard Schoen<br>1994 | Leon Simon<br>1999 | D. Christodoulou; S. Klainerman; Thomas Wolff<br>2002 | Daneil Tătaru; Terence Tao; Fanghu Lin<br>2005 | Frank Merle<br>2008 | A. Bressan; C. Fefferman; C. Kenig<br>2011 | Assaf Naor; G. Uhlmann<br>2014 | Simon Brendle<br>2017 | András Vasy<br>2020 | C. De Lellis; L. Guth; L. S.-Raymond<br>2023 | F. Merle, P. Raphaël, I. Rodnianski, J. Szeftel</p><p>1938 年, 因此项工作, von Neumann 获得了美国数学会颁发的博歇尔(Maxime Bôcher, 1867-1918)奖。</p><p>在 1933 年的一篇论文中,他利用新发现的 Haar 测度解决了 Hilbert 第五问题中针对紧群(compact groups)的部分。这一核心思想在数年前即已浮现:当时 von Neumann 发表了一篇关于线性变换群解析性质的论文,指出一般线性群(general linear group)的闭子群实际上是李群(Lie groups)。</p><p>Über die analytischen Eigenschaften von Gruppen linearer Transformationen und ihrer Darstellungen</p><p>这一结果后来被埃利・嘉当(Élie Joseph Cartan, 1869-1951)推广到任意李群,现称作闭子群定理(closed-subgroup theorem)——<br>If<mjx-container class="MathJax" jax="SVG" overflow="overflow"><svg style="vertical-align:0" xmlns="http://www.w3.org/2000/svg" width="1.993ex" height="1.545ex" role="img" focusable="false" viewBox="0 -683 881 683"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(1,-1)"><g data-mml-node="math" data-latex="H"><g data-mml-node="mi" data-latex="H"><path data-c="1D43B" d="M881 668C881 678 875 683 863 683L736 680 609 683C593 683 586 674 586 659 586 652 589 647 594 646 604 645 612 644 617 644 648 643 665 641 670 640 675 639 678 636 678 631 677 628 676 622 674 613L615 375 321 375 379 602C384 623 393 636 406 641 413 643 430 644 458 644 485 644 496 644 496 668 496 678 490 683 478 683L351 680 223 683C207 683 200 674 200 659 200 652 203 647 209 646 219 645 227 644 232 644 263 643 281 641 286 640 291 639 293 636 293 631 293 629 292 623 289 613L156 82C151 60 141 47 126 42 119 40 101 39 70 39 48 39 39 37 39 15 39 5 45 0 57 0L183 3 246 2C257 2 299 0 310 0 326 0 334 8 334 24 334 34 323 39 302 39 262 39 242 43 242 52 242 52 243 55 245 68L312 336 605 336 538 68C535 53 523 43 503 40 498 39 481 39 452 39 433 39 424 31 424 15 424 5 430 0 442 0L568 3 631 2C642 2 683 0 696 0 712 0 720 8 720 24 720 34 709 39 688 39 647 39 627 43 627 52 627 52 628 55 630 68L764 602C769 623 778 636 791 641 797 643 814 644 843 644 869 644 881 644 881 668Z"></path></g></g></g></svg></mjx-container> is a closed subgroup of a Lie group<mjx-container class="MathJax" jax="SVG" overflow="overflow"><svg style="vertical-align:-.05ex" xmlns="http://www.w3.org/2000/svg" width="1.778ex" height="1.645ex" role="img" focusable="false" viewBox="0 -705 786 727"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(1,-1)"><g data-mml-node="math" data-latex="G"><g data-mml-node="mi" data-latex="G"><path data-c="1D43A" d="M324-22C412-22 481 5 532 59 538 46 564 1 578 1 583 1 586 4 588 8 590 12 597 32 606 68L624 144C630 167 634 184 637 195 648 239 648 238 702 239 715 239 721 247 721 263 721 273 716 278 705 278 686 278 620 274 601 275L462 278C446 278 438 270 438 254 438 245 444 241 456 240 513 237 543 235 546 233 549 231 550 227 550 222 550 215 543 185 530 133 510 61 436 17 343 17 221 17 148 98 148 220 148 239 150 263 153 290 164 372 218 487 261 540 311 603 403 666 505 666 609 666 660 587 660 479 660 470 657 438 657 429 657 420 663 415 676 415 681 415 685 416 688 417 693 424 696 431 698 438L760 691C760 700 755 705 745 705 741 705 735 701 727 692L662 619C623 676 568 705 497 705 442 705 388 692 333 667 222 615 141 533 89 421 63 366 50 310 50 253 50 93 164-22 324-22Z"></path></g></g></g></svg></mjx-container>, then<mjx-container class="MathJax" jax="SVG" overflow="overflow"><svg style="vertical-align:0" xmlns="http://www.w3.org/2000/svg" width="1.993ex" height="1.545ex" role="img" focusable="false" viewBox="0 -683 881 683"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(1,-1)"><g data-mml-node="math" data-latex="H"><g data-mml-node="mi" data-latex="H"><path data-c="1D43B" d="M881 668C881 678 875 683 863 683L736 680 609 683C593 683 586 674 586 659 586 652 589 647 594 646 604 645 612 644 617 644 648 643 665 641 670 640 675 639 678 636 678 631 677 628 676 622 674 613L615 375 321 375 379 602C384 623 393 636 406 641 413 643 430 644 458 644 485 644 496 644 496 668 496 678 490 683 478 683L351 680 223 683C207 683 200 674 200 659 200 652 203 647 209 646 219 645 227 644 232 644 263 643 281 641 286 640 291 639 293 636 293 631 293 629 292 623 289 613L156 82C151 60 141 47 126 42 119 40 101 39 70 39 48 39 39 37 39 15 39 5 45 0 57 0L183 3 246 2C257 2 299 0 310 0 326 0 334 8 334 24 334 34 323 39 302 39 262 39 242 43 242 52 242 52 243 55 245 68L312 336 605 336 538 68C535 53 523 43 503 40 498 39 481 39 452 39 433 39 424 31 424 15 424 5 430 0 442 0L568 3 631 2C642 2 683 0 696 0 712 0 720 8 720 24 720 34 709 39 688 39 647 39 627 43 627 52 627 52 628 55 630 68L764 602C769 623 778 636 791 641 797 643 814 644 843 644 869 644 881 644 881 668Z"></path></g></g></g></svg></mjx-container> is an embedded Lie group with the smooth structure agreeing with the embedding。</p><h3 id="七、泛函分析(Functional-analysis)"><a href="#七、泛函分析(Functional-analysis)" class="headerlink" title="七、泛函分析(Functional analysis)"></a>七、泛函分析(Functional analysis)</h3><p>von Neumann 首次从公理化角度给出了抽象 Hilbert 空间的定义:这是一个带有埃尔米特(Hermitian)内积的复向量空间,其对应范数既可分又完备(separable and complete)。</p><p>在同样的论文中,他也证明了先前只在特定情形下已知的 Cauchy–Schwarz 不等式的一般形式。</p><p>1929 年至 1932 年间,他又在三篇奠基性的论文中继续发展了 Hilbert 空间中算子的谱理论(spectral theory)。</p><p>这些工作最终汇编进他的著作《量子力学的数学基础》(Mathematical Foundations of Quantum Mechanics)。与 Stone 和 Banach 在同一年出版的两本著作一起,它们是最早的 Hilbert 空间理论专著。</p><p>在此前他人的研究中,人们已发现仅靠序列(sequence)无法获得弱拓扑(weak topology)理论。von Neumann 是首位提出如何克服这一困难的方案的人,由此他首次定义了局部凸空间(locally convex spaces)和拓扑向量空间(topological vector spaces)。</p><p>此外,他当时还定义了诸如有界性(boundness)及全局有界性(total boundness)等几个拓扑性质,这些概念至今仍然十分重要。</p><p>von Neumann 发展上述理论的主要动机来源于量子力学:von Neumann 认识到必须将 Hermitian 算子的谱理论从有界情形推广到无界情形。</p><p>von Neumann 还在一篇论文中详细论述了:当时在谱理论中常用的 “无限矩阵” 方法不足以对 Hermitian 算子进行恰当表示。他在算子理论上的研究最终引领他创造了纯数学中最深远的发明之一 ——von Neumann 代数以及更一般的算子代数理论。</p><p>在此阶段,von Neumann 重新审视了自己在谱理论方面的研究,并在 “算子环”(rings of operators)领域进一步发展了相关思想。</p><p>他通过在 Hilbert 空间中使用 direct integrals 的手段,赋予了谱理论全新的几何解释,同时也在不变子空间问题上取得突破,却因为各种原因未能及时发表部分成果。</p><p>例如,他曾在 20 世纪 30 年代早期向阿隆沙因(Nachman Aronszajn, 1907-1980)和 K. T. Smith 透露,自己已证明了完全连续算子在 Hilbert 空间中必然存在适当的不变子空间(the existence of proper invariant subspaces for completely continuous operators in a Hilbert space)。</p><p>在与伊萨克・雅各布・勋伯格(Issac Jacob Schoenberg, 1903-1990)合作的过程中,von Neumann 对实数上的平移不变的 Hilbert 度量进行了完整分类。</p><p>在与恩斯特・帕斯夸尔・约当(Ernst Pascual Jordan, 1902-1980)的合作中,提出了酉不变范数(unitarily invariant norms)与对称规函数(symmetric gauge functions)的系统讨论,开启了对称算子理想(symmetric operator ideals)和对称算子空间(symmetric operator space)的研究。</p><p>在与罗伯特・沙顿(Robert Schatten, 1911-1977)合作时,开创了对核算子(nuclear operators)与 Banach 空间张量积的研究,引入并探讨了迹类算子(trace class operators)及其与紧算子和有界算子的对偶(duality)及预对偶(preduality)关系。</p><p>随后,亚历山大・格罗滕迪克(Alexander Grothendieck, 1928-2014)等人又将这一方向推广到 Banach 空间的核算子理论。</p><p>实际上,von Neumann 早在 1937 年就发表了若干相关结果,包括对<mjx-container class="MathJax" jax="SVG" overflow="overflow"><svg style="vertical-align:-.669ex" xmlns="http://www.w3.org/2000/svg" width="2.091ex" height="2.366ex" role="img" focusable="false" viewBox="0 -750 924.3 1045.7"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(1,-1)"><g data-mml-node="math" data-latex="\ell_2^n \otimes \ell_2^n"><g data-mml-node="msubsup" data-latex="\ell_2^n"><g data-mml-node="mi" data-latex="\ell"><path data-c="2113" d="M317 392C371 473 398 551 398 624 398 678 377 705 336 705 297 705 260 676 223 617 200 580 182 547 169 517 117 398 91 284 91 176L17 104C13 99 11 95 11 92 11 81 16 75 27 75 31 75 53 95 94 135 108 37 146-12 207-12 244-12 289 11 341 58 357 72 365 82 365 88 365 99 360 104 349 104 346 104 341 101 334 94 282 43 240 18 209 18 172 18 153 59 153 142 153 202 152 195 178 221 227 270 274 327 317 392M337 675C357 675 367 659 367 628 367 521 300 396 165 252 179 331 229 515 262 585 291 645 316 675 337 675Z"></path></g><g data-mml-node="mi" transform="translate(450,363) scale(0.707)" data-latex="n"><path data-c="1D45B" d="M537 137C514 58 481 18 440 18 427 18 420 28 420 47 420 61 426 84 438 115 478 224 498 296 498 333 498 403 451 442 381 442 322 442 271 416 230 363 222 407 187 442 136 442 80 442 58 390 44 345 34 313 29 294 29 287 29 278 34 273 45 273 50 273 53 274 56 276 61 285 64 292 65 299 83 375 106 413 133 413 151 413 160 399 160 371 160 358 155 331 144 290L87 63C84 50 78 24 78 19 78-1 89-11 111-11 130-11 144-1 151 19 153 24 159 49 170 92L191 181 221 295C232 318 249 341 270 365 299 397 335 413 378 413 411 413 427 391 427 348 427 310 406 234 363 120 356 102 353 87 353 74 353 25 390-11 438-11 482-11 517 14 542 64 561 104 571 131 571 144 571 153 566 158 555 158 552 158 537 149 537 137Z"></path></g><g data-mml-node="mn" transform="translate(450,-295.7) scale(0.707)" data-latex="2"><path data-c="32" d="M237 666C186 666 143 648 106 612 69 576 50 534 50 483 50 449 75 424 106 424 136 424 161 450 161 480 161 513 137 536 105 536 102 536 100 536 98 535 117 584 161 627 224 627 306 627 352 556 352 470 352 403 318 331 250 255L62 43C49 28 50 29 50 0L421 0 450 180 417 180C409 129 402 100 396 91 391 86 361 84 306 84L139 84 236 179C304 243 390 312 419 365 439 400 449 435 449 470 449 588 357 666 237 666Z"></path></g></g></g></g></svg><mjx-break size="3"></mjx-break><svg style="vertical-align:-.669ex" xmlns="http://www.w3.org/2000/svg" width="4.363ex" height="2.366ex" role="img" focusable="false" viewBox="0 -750 1928.5 1045.7"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(1,-1)"><g data-mml-node="math" data-latex="\ell_2^n \otimes \ell_2^n"><g data-mml-node="mo" data-latex="\otimes"><path data-c="2297" d="M48 249C48 60 201-93 390-93 579-93 732 60 732 249 732 438 579 591 390 591 201 591 48 438 48 249M615 58 423 250 614 441C658 389 685 322 685 249 685 176 659 110 615 58M198 475C250 519 316 545 389 545 462 545 528 519 580 475L389 284M581 24C529-20 462-47 389-47 316-47 249-20 197 24L389 216M164 441 355 250 163 58C119 110 93 176 93 249 93 322 120 389 164 441Z"></path></g><g data-mml-node="msubsup" data-latex="\ell_2^n" transform="translate(1004.2,0)"><g data-mml-node="mi" data-latex="\ell"><path data-c="2113" d="M317 392C371 473 398 551 398 624 398 678 377 705 336 705 297 705 260 676 223 617 200 580 182 547 169 517 117 398 91 284 91 176L17 104C13 99 11 95 11 92 11 81 16 75 27 75 31 75 53 95 94 135 108 37 146-12 207-12 244-12 289 11 341 58 357 72 365 82 365 88 365 99 360 104 349 104 346 104 341 101 334 94 282 43 240 18 209 18 172 18 153 59 153 142 153 202 152 195 178 221 227 270 274 327 317 392M337 675C357 675 367 659 367 628 367 521 300 396 165 252 179 331 229 515 262 585 291 645 316 675 337 675Z"></path></g><g data-mml-node="mi" transform="translate(450,363) scale(0.707)" data-latex="n"><path data-c="1D45B" d="M537 137C514 58 481 18 440 18 427 18 420 28 420 47 420 61 426 84 438 115 478 224 498 296 498 333 498 403 451 442 381 442 322 442 271 416 230 363 222 407 187 442 136 442 80 442 58 390 44 345 34 313 29 294 29 287 29 278 34 273 45 273 50 273 53 274 56 276 61 285 64 292 65 299 83 375 106 413 133 413 151 413 160 399 160 371 160 358 155 331 144 290L87 63C84 50 78 24 78 19 78-1 89-11 111-11 130-11 144-1 151 19 153 24 159 49 170 92L191 181 221 295C232 318 249 341 270 365 299 397 335 413 378 413 411 413 427 391 427 348 427 310 406 234 363 120 356 102 353 87 353 74 353 25 390-11 438-11 482-11 517 14 542 64 561 104 571 131 571 144 571 153 566 158 555 158 552 158 537 149 537 137Z"></path></g><g data-mml-node="mn" transform="translate(450,-295.7) scale(0.707)" data-latex="2"><path data-c="32" d="M237 666C186 666 143 648 106 612 69 576 50 534 50 483 50 449 75 424 106 424 136 424 161 450 161 480 161 513 137 536 105 536 102 536 100 536 98 535 117 584 161 627 224 627 306 627 352 556 352 470 352 403 318 331 250 255L62 43C49 28 50 29 50 0L421 0 450 180 417 180C409 129 402 100 396 91 391 86 361 84 306 84L139 84 236 179C304 243 390 312 419 365 439 400 449 435 449 470 449 588 357 666 237 666Z"></path></g></g></g></g></svg></mjx-container> 上不同交叉范数的刻度,以及后来被称为 Schatten-von Neumann ideals 的其他相关结果。</p><p>在与罗伯特・沙顿(Robert Schatten, 1911-1977)合作时,开创了对核算子(nuclear operators)与 Banach 空间张量积的研究,引入并探讨了迹类算子(trace class operators)及其与紧算子和有界算子的对偶(duality)及预对偶(preduality)关系。</p><h3 id="八、算子代数(Operator-algebras)"><a href="#八、算子代数(Operator-algebras)" class="headerlink" title="八、算子代数(Operator algebras)"></a>八、算子代数(Operator algebras)</h3><p>通过对 “算子环” 的研究,John von Neumann 开创了对 von Neumann 代数(最初称为<mjx-container class="MathJax" jax="SVG" overflow="overflow"><svg style="vertical-align:-.05ex" xmlns="http://www.w3.org/2000/svg" width="3.484ex" height="1.61ex" role="img" focusable="false" viewBox="0 -689.7 1539.8 711.7"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(1,-1)"><g data-mml-node="math" data-latex="W^*"><g data-mml-node="msup" data-latex="W^*"><g data-mml-node="mi" data-latex="W"><path data-c="1D44A" d="M956 680C937 680 872 683 853 683 838 683 830 675 830 660 830 650 836 645 848 644 885 643 903 632 903 610 903 604 899 594 891 579L629 125 594 602C590 638 614 644 659 644 680 644 690 652 690 668 690 678 684 683 671 683 649 683 572 680 550 680 531 680 465 683 446 683 431 683 423 675 423 659 423 649 432 644 451 644 482 644 498 637 499 623L505 548 261 125 225 613C222 638 264 644 296 644 313 644 321 652 321 668 321 678 315 683 303 683 281 683 203 680 181 680 162 680 96 683 77 683 62 683 55 675 55 660 55 649 65 644 84 644 126 644 130 642 132 612L177 7C178-12 185-22 197-22 210-20 215-17 223-2 224-1 224 0 224 1L509 494 545 7C546-12 553-22 565-22 575-22 584-15 592-1L918 562C945 611 964 639 1025 644 1043 646 1048 651 1048 668 1048 678 1043 683 1032 683 1018 683 970 680 956 680Z"></path></g><g data-mml-node="mo" transform="translate(1136.2,363) scale(0.707)" data-latex="*"><path data-c="2217" d="M404 372C397 372 390 370 385 366L267 279 282 425C285 445 269 462 250 462 231 462 215 445 218 425L233 279 115 366C110 370 103 372 96 372 78 372 63 357 63 339 63 325 70 315 83 309L217 250 83 191C70 185 63 175 63 161 63 143 78 128 96 128 103 128 110 130 115 134L233 221 218 75C215 55 231 39 250 39 269 39 285 55 282 75L267 221 385 134C390 130 397 128 404 128 415 128 424 133 431 142 446 162 435 183 417 191L283 250 417 309C430 315 437 325 437 339 437 357 422 372 404 372Z"></path></g></g></g></g></svg></mjx-container> - 代数)的系统研究。他早在 1930 年前便有了初步设想,但直到与弗朗西斯・约瑟夫・默里(Francis Joseph Murray, 1911-1996)相识后,才在数年内将其发展为一套完整的理论。von Neumann 代数是指希尔伯特空间上在关于弱算子拓扑下是闭的、包含恒等算子的一类有界算子构成的 <em>- 代数(</em>-algebra)。</p><p>von Neumann 的 “von Neumann bicommutant theorem” 证明了要验证上述解析的定义可以通过纯代数方式验证。<br>von Neumann bicommutant theorem 是说,Let<mjx-container class="MathJax" jax="SVG" overflow="overflow"><svg style="vertical-align:0" xmlns="http://www.w3.org/2000/svg" width="2.362ex" height="1.545ex" role="img" focusable="false" viewBox="0 -683 1044 683"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(1,-1)"><g data-mml-node="math" data-latex="M"><g data-mml-node="mi" data-latex="M"><path data-c="1D440" d="M594 16C594 5 600 0 613 0L736 3C759 4 840 0 859 0 874 0 882 8 882 24 882 34 872 39 851 39 810 39 790 43 790 52 790 55 792 62 795 75L927 602C932 623 942 636 955 641 961 643 979 644 1008 644 1033 644 1044 645 1044 668 1044 678 1034 683 1013 683L882 683C853 683 853 681 840 662L484 108 408 657C404 682 402 683 373 683L237 683C215 683 204 682 204 660 204 649 215 644 236 644 256 644 297 647 297 631 297 629 296 623 293 613L167 110C158 72 135 49 100 42 75 39 42 43 42 16 42 5 48 0 60 0 78 0 141 3 159 3 178 3 242 0 261 0 276 0 283 8 283 24 283 33 276 38 261 39 219 39 198 52 198 78 198 82 199 89 202 100L332 621 415 26C418 9 424 0 434 0 442 0 450 7 459 20L848 627 712 82C706 60 696 47 681 42 675 40 656 39 625 39 604 39 594 37 594 16Z"></path></g></g></g></svg></mjx-container> be an algebra consisting of bounded operators on a Hilbert space<mjx-container class="MathJax" jax="SVG" overflow="overflow"><svg style="vertical-align:0" xmlns="http://www.w3.org/2000/svg" width="1.993ex" height="1.545ex" role="img" focusable="false" viewBox="0 -683 881 683"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(1,-1)"><g data-mml-node="math" data-latex="H"><g data-mml-node="mi" data-latex="H"><path data-c="1D43B" d="M881 668C881 678 875 683 863 683L736 680 609 683C593 683 586 674 586 659 586 652 589 647 594 646 604 645 612 644 617 644 648 643 665 641 670 640 675 639 678 636 678 631 677 628 676 622 674 613L615 375 321 375 379 602C384 623 393 636 406 641 413 643 430 644 458 644 485 644 496 644 496 668 496 678 490 683 478 683L351 680 223 683C207 683 200 674 200 659 200 652 203 647 209 646 219 645 227 644 232 644 263 643 281 641 286 640 291 639 293 636 293 631 293 629 292 623 289 613L156 82C151 60 141 47 126 42 119 40 101 39 70 39 48 39 39 37 39 15 39 5 45 0 57 0L183 3 246 2C257 2 299 0 310 0 326 0 334 8 334 24 334 34 323 39 302 39 262 39 242 43 242 52 242 52 243 55 245 68L312 336 605 336 538 68C535 53 523 43 503 40 498 39 481 39 452 39 433 39 424 31 424 15 424 5 430 0 442 0L568 3 631 2C642 2 683 0 696 0 712 0 720 8 720 24 720 34 709 39 688 39 647 39 627 43 627 52 627 52 628 55 630 68L764 602C769 623 778 636 791 641 797 643 814 644 843 644 869 644 881 644 881 668Z"></path></g></g></g></svg></mjx-container>, containing the identity operator, and closed under taking adjoints. Then the closures of<mjx-container class="MathJax" jax="SVG" overflow="overflow"><svg style="vertical-align:0" xmlns="http://www.w3.org/2000/svg" width="2.362ex" height="1.545ex" role="img" focusable="false" viewBox="0 -683 1044 683"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(1,-1)"><g data-mml-node="math" data-latex="M"><g data-mml-node="mi" data-latex="M"><path data-c="1D440" d="M594 16C594 5 600 0 613 0L736 3C759 4 840 0 859 0 874 0 882 8 882 24 882 34 872 39 851 39 810 39 790 43 790 52 790 55 792 62 795 75L927 602C932 623 942 636 955 641 961 643 979 644 1008 644 1033 644 1044 645 1044 668 1044 678 1034 683 1013 683L882 683C853 683 853 681 840 662L484 108 408 657C404 682 402 683 373 683L237 683C215 683 204 682 204 660 204 649 215 644 236 644 256 644 297 647 297 631 297 629 296 623 293 613L167 110C158 72 135 49 100 42 75 39 42 43 42 16 42 5 48 0 60 0 78 0 141 3 159 3 178 3 242 0 261 0 276 0 283 8 283 24 283 33 276 38 261 39 219 39 198 52 198 78 198 82 199 89 202 100L332 621 415 26C418 9 424 0 434 0 442 0 450 7 459 20L848 627 712 82C706 60 696 47 681 42 675 40 656 39 625 39 604 39 594 37 594 16Z"></path></g></g></g></svg></mjx-container> in the weak operator topology and the strong operator topology are equal, and are in turn equal to the bicommutant<mjx-container class="MathJax" jax="SVG" overflow="overflow"><svg style="vertical-align:0" xmlns="http://www.w3.org/2000/svg" width="3.706ex" height="1.7ex" role="img" focusable="false" viewBox="0 -751.2 1638.2 751.2"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(1,-1)"><g data-mml-node="math" data-latex="M''"><g data-mml-node="msup" data-latex="M''"><g data-mml-node="mi" data-latex="M"><path data-c="1D440" d="M594 16C594 5 600 0 613 0L736 3C759 4 840 0 859 0 874 0 882 8 882 24 882 34 872 39 851 39 810 39 790 43 790 52 790 55 792 62 795 75L927 602C932 623 942 636 955 641 961 643 979 644 1008 644 1033 644 1044 645 1044 668 1044 678 1034 683 1013 683L882 683C853 683 853 681 840 662L484 108 408 657C404 682 402 683 373 683L237 683C215 683 204 682 204 660 204 649 215 644 236 644 256 644 297 647 297 631 297 629 296 623 293 613L167 110C158 72 135 49 100 42 75 39 42 43 42 16 42 5 48 0 60 0 78 0 141 3 159 3 178 3 242 0 261 0 276 0 283 8 283 24 283 33 276 38 261 39 219 39 198 52 198 78 198 82 199 89 202 100L332 621 415 26C418 9 424 0 434 0 442 0 450 7 459 20L848 627 712 82C706 60 696 47 681 42 675 40 656 39 625 39 604 39 594 37 594 16Z"></path></g><g data-mml-node="mo" transform="translate(1130.7,363) scale(0.707)" data-latex="'"><path data-c="2033" d="M523 549C497 549 480 539 472 518L301 96 347 96 572 463C577 472 580 482 580 493 580 523 553 549 523 549M287 549C261 549 244 539 236 518L65 96 111 96 335 463C341 472 344 482 344 493 344 523 317 549 287 549Z"></path></g></g></g></g></svg></mjx-container> of<mjx-container class="MathJax" jax="SVG" overflow="overflow"><svg style="vertical-align:0" xmlns="http://www.w3.org/2000/svg" width="2.362ex" height="1.545ex" role="img" focusable="false" viewBox="0 -683 1044 683"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(1,-1)"><g data-mml-node="math" data-latex="M"><g data-mml-node="mi" data-latex="M"><path data-c="1D440" d="M594 16C594 5 600 0 613 0L736 3C759 4 840 0 859 0 874 0 882 8 882 24 882 34 872 39 851 39 810 39 790 43 790 52 790 55 792 62 795 75L927 602C932 623 942 636 955 641 961 643 979 644 1008 644 1033 644 1044 645 1044 668 1044 678 1034 683 1013 683L882 683C853 683 853 681 840 662L484 108 408 657C404 682 402 683 373 683L237 683C215 683 204 682 204 660 204 649 215 644 236 644 256 644 297 647 297 631 297 629 296 623 293 613L167 110C158 72 135 49 100 42 75 39 42 43 42 16 42 5 48 0 60 0 78 0 141 3 159 3 178 3 242 0 261 0 276 0 283 8 283 24 283 33 276 38 261 39 219 39 198 52 198 78 198 82 199 89 202 100L332 621 415 26C418 9 424 0 434 0 442 0 450 7 459 20L848 627 712 82C706 60 696 47 681 42 675 40 656 39 625 39 604 39 594 37 594 16Z"></path></g></g></g></svg></mjx-container> 。</p><p>在成功处理了交换代数的情况后,von Neumann 与 Murray 自 1936 年起进一步研究非交换情形,主要聚焦于对 “factors” 的分类,以及 von Neumann 代数的整体框架。</p><p>他们于 1936 至 1940 年间发表的六篇重要论文被誉为 20 世纪分析领域的杰作,奠定了算子代数的一系列基础结果,并引领了多个后续方向。其中包括 factors 的分类方法,以及对可分希尔伯特空间(separable Hilbert space)上的 von Neumann 代数 is a direct integral of factors 的证明(1938 年提出,直至 1949 年才发表)。</p><p>孔涅(Alain Connes, 1947-)后来对于因子的结构和分类的工作获得了 1982 年的菲尔兹奖。此外,von Neumann 代数还与非交换积分理论密切相关,他虽在著作中暗示了这一点却未明确写出;另一个里程碑式成果是 1932 年提出的极分解(polar decomposition)定理。</p><h3 id="九、格论(Lattice-theory)"><a href="#九、格论(Lattice-theory)" class="headerlink" title="九、格论(Lattice theory)"></a>九、格论(Lattice theory)</h3><p>von Neumann 将传统的射影几何与线性代数、环论、格论等现代代数工具相融合,使得射影几何中的许多结果都能在一般的环上模(modules over rings)里得到推广和解释。<br>他提出了连续几何(continuous geometry)的概念,它是对复射影几何的一种替代。</p><p>传统射影几何的维度只能取离散值(0、1、2、……),而在连续几何中,子空间的维度可以在<mjx-container class="MathJax" jax="SVG" overflow="overflow"><svg style="vertical-align:-.566ex" xmlns="http://www.w3.org/2000/svg" width="4.526ex" height="2.262ex" role="img" focusable="false" viewBox="0 -750 2000.7 1000"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(1,-1)"><g data-mml-node="math" data-latex="[0,1] "><g data-mml-node="mo" data-latex="["><path data-c="5B" d="M233-202 159-202 159 702 233 702C248 702 256 710 256 726 256 742 248 750 233 750L114 750 114-250 233-250C248-250 256-242 256-226 256-214 245-202 233-202Z"></path></g><g data-mml-node="mn" data-latex="0" transform="translate(278,0)"><path data-c="30" d="M249-22C390-22 460 92 460 320 460 473 428 575 365 625 330 652 291 666 250 666 109 666 39 551 39 320 39 136 88-22 249-22M361 524C368 489 371 425 371 332 371 240 367 172 360 128 347 48 310 8 249 8 226 8 203 17 182 34 155 57 139 104 132 176 129 201 128 253 128 332 128 419 131 480 136 513 145 568 163 603 191 618 213 630 232 636 249 636 314 636 350 583 361 524Z"></path></g><g data-mml-node="mo" data-latex="," transform="translate(778,0)"><path data-c="2C" d="M139 106C107 106 86 82 86 50 86 20 109-5 139-5 153-5 165-1 174 8L175 0C175-63 154-117 112-160 105-168 101-174 101-178 101-188 105-193 114-193 123-193 135-181 152-158 186-110 203-57 203 0 203 53 185 106 139 106Z"></path></g><g data-mml-node="mn" data-latex="1" transform="translate(1222.7,0)"><path data-c="31" d="M269 666C228 624 168 603 89 603L89 564C141 564 184 572 217 588L217 82C217 64 213 52 204 47 195 42 170 39 130 39L95 39 95 0C120 2 174 3 257 3 340 3 394 2 419 0L419 39 384 39C343 39 318 42 310 47 302 52 297 64 297 82L297 636C297 660 295 666 269 666Z"></path></g><g data-mml-node="mo" data-latex="]" transform="translate(1722.7,0)"><path data-c="5D" d="M45-250 164-250 164 750 45 750C30 750 22 742 22 726 22 710 30 702 45 702L119 702 119-202 45-202C30-202 22-210 22-226 22-242 30-250 45-250Z"></path></g></g></g></svg></mjx-container> 区间里连续变化。</p><p>这一想法源自 von Neumann 对于一类 II 型 factor 等算子代数的研究,那里出现了可取连续值的 “维度函数”。</p><p>von Neumann 以格论的抽象语言刻画了带连续维度的射影几何,并将传统射影几何的 Veblen(Oswald Veblen, 1880-1960)- Young(John Wesley Young, 1879-1932)定理(a projective space of dimension at least 3 can be constructed as the projective space associated to a vector space over a division ring)推广到他提出的连续几何的框架中。</p><p>为了证明相关定理,他提出了 von Neumann 正则环(von Neumann regular ring)的概念,即对任意环元素<mjx-container class="MathJax" jax="SVG" overflow="overflow"><svg style="vertical-align:-.025ex" xmlns="http://www.w3.org/2000/svg" width="1.197ex" height="1.025ex" role="img" focusable="false" viewBox="0 -442 529 453"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(1,-1)"><g data-mml-node="math" data-latex="a"><g data-mml-node="mi" data-latex="a"><path data-c="1D44E" d="M498 144C498 153 493 158 482 158 474 158 468 151 465 137 445 58 421 18 394 18 377 18 368 32 368 60 368 73 372 97 381 132L438 357C443 376 445 387 445 392 445 412 434 422 412 422 391 422 377 410 370 387 349 424 319 442 281 442 216 442 159 409 109 343 63 281 40 217 40 150 40 63 91-11 175-11 218-11 260 12 300 58 311 20 345-11 392-11 461-11 482 70 498 144M341 374C350 353 355 339 355 330 355 326 354 321 353 314L304 122C301 111 294 99 285 87 248 41 212 18 177 18 138 18 118 48 118 107 118 131 124 167 136 215 157 300 187 357 224 388 244 405 263 413 282 413 309 413 329 400 341 374Z"></path></g></g></g></svg></mjx-container> ,存在<mjx-container class="MathJax" jax="SVG" overflow="overflow"><svg style="vertical-align:-.025ex" xmlns="http://www.w3.org/2000/svg" width="1.294ex" height="1.025ex" role="img" focusable="false" viewBox="0 -442 572 453"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(1,-1)"><g data-mml-node="math" data-latex="x"><g data-mml-node="mi" data-latex="x"><path data-c="1D465" d="M527 373C527 419 482 442 432 442 389 442 355 419 329 373 308 419 273 442 222 442 173 442 133 419 101 374 74 335 60 306 60 287 60 278 65 273 75 273 84 273 90 278 92 287 111 345 153 413 220 413 253 413 269 392 269 351 269 330 251 252 216 118 199 51 169 18 126 18 112 18 99 21 88 26 114 36 127 54 127 80 127 106 114 119 87 119 54 119 29 91 29 58 29 12 76-11 125-11 167-11 201 12 228 58 247 12 283-11 335-11 383-11 423 12 455 57 482 96 496 125 496 144 496 153 491 158 481 158 472 158 467 153 464 144 447 87 402 18 337 18 304 18 287 38 287 79 287 92 292 120 303 165L337 300C356 375 387 413 431 413 445 413 458 410 469 405 442 396 429 378 429 351 429 325 443 312 470 312 502 312 527 341 527 373Z"></path></g></g></g></svg></mjx-container> 使得<mjx-container class="MathJax" jax="SVG" overflow="overflow"><svg style="vertical-align:-.566ex" xmlns="http://www.w3.org/2000/svg" width="3.688ex" height="2.262ex" role="img" focusable="false" viewBox="0 -750 1630 1000"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(1,-1)"><g data-mml-node="math" data-latex="axa = x"><g data-mml-node="mi" data-latex="a"><path data-c="1D44E" d="M498 144C498 153 493 158 482 158 474 158 468 151 465 137 445 58 421 18 394 18 377 18 368 32 368 60 368 73 372 97 381 132L438 357C443 376 445 387 445 392 445 412 434 422 412 422 391 422 377 410 370 387 349 424 319 442 281 442 216 442 159 409 109 343 63 281 40 217 40 150 40 63 91-11 175-11 218-11 260 12 300 58 311 20 345-11 392-11 461-11 482 70 498 144M341 374C350 353 355 339 355 330 355 326 354 321 353 314L304 122C301 111 294 99 285 87 248 41 212 18 177 18 138 18 118 48 118 107 118 131 124 167 136 215 157 300 187 357 224 388 244 405 263 413 282 413 309 413 329 400 341 374Z"></path></g><g data-mml-node="mi" data-latex="x" transform="translate(529,0)"><path data-c="1D465" d="M527 373C527 419 482 442 432 442 389 442 355 419 329 373 308 419 273 442 222 442 173 442 133 419 101 374 74 335 60 306 60 287 60 278 65 273 75 273 84 273 90 278 92 287 111 345 153 413 220 413 253 413 269 392 269 351 269 330 251 252 216 118 199 51 169 18 126 18 112 18 99 21 88 26 114 36 127 54 127 80 127 106 114 119 87 119 54 119 29 91 29 58 29 12 76-11 125-11 167-11 201 12 228 58 247 12 283-11 335-11 383-11 423 12 455 57 482 96 496 125 496 144 496 153 491 158 481 158 472 158 467 153 464 144 447 87 402 18 337 18 304 18 287 38 287 79 287 92 292 120 303 165L337 300C356 375 387 413 431 413 445 413 458 410 469 405 442 396 429 378 429 351 429 325 443 312 470 312 502 312 527 341 527 373Z"></path></g><g data-mml-node="mi" data-latex="a" transform="translate(1101,0)"><path data-c="1D44E" d="M498 144C498 153 493 158 482 158 474 158 468 151 465 137 445 58 421 18 394 18 377 18 368 32 368 60 368 73 372 97 381 132L438 357C443 376 445 387 445 392 445 412 434 422 412 422 391 422 377 410 370 387 349 424 319 442 281 442 216 442 159 409 109 343 63 281 40 217 40 150 40 63 91-11 175-11 218-11 260 12 300 58 311 20 345-11 392-11 461-11 482 70 498 144M341 374C350 353 355 339 355 330 355 326 354 321 353 314L304 122C301 111 294 99 285 87 248 41 212 18 177 18 138 18 118 48 118 107 118 131 124 167 136 215 157 300 187 357 224 388 244 405 263 413 282 413 309 413 329 400 341 374Z"></path></g></g></g></svg><mjx-break size="4"></mjx-break><svg style="vertical-align:-.566ex" xmlns="http://www.w3.org/2000/svg" width="3.683ex" height="2.262ex" role="img" focusable="false" viewBox="0 -750 1627.8 1000"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(1,-1)"><g data-mml-node="math" data-latex="axa = x"><g data-mml-node="mo" data-latex="="><path data-c="3D" d="M698 367 80 367C64 367 56 359 56 344 56 329 64 321 80 321L698 321C714 321 722 329 722 344 722 356 711 367 698 367M698 179 80 179C64 179 56 171 56 156 56 141 64 133 80 133L698 133C714 133 722 141 722 156 722 169 711 179 698 179Z"></path></g><g data-mml-node="mi" data-latex="x" transform="translate(1055.8,0)"><path data-c="1D465" d="M527 373C527 419 482 442 432 442 389 442 355 419 329 373 308 419 273 442 222 442 173 442 133 419 101 374 74 335 60 306 60 287 60 278 65 273 75 273 84 273 90 278 92 287 111 345 153 413 220 413 253 413 269 392 269 351 269 330 251 252 216 118 199 51 169 18 126 18 112 18 99 21 88 26 114 36 127 54 127 80 127 106 114 119 87 119 54 119 29 91 29 58 29 12 76-11 125-11 167-11 201 12 228 58 247 12 283-11 335-11 383-11 423 12 455 57 482 96 496 125 496 144 496 153 491 158 481 158 472 158 467 153 464 144 447 87 402 18 337 18 304 18 287 38 287 79 287 92 292 120 303 165L337 300C356 375 387 413 431 413 445 413 458 410 469 405 442 396 429 378 429 351 429 325 443 312 470 312 502 312 527 341 527 373Z"></path></g></g></g></svg></mjx-container> 。</p><p>该概念与后来的 von Neumann 代数等研究紧密关联。在此过程中还创造并证明了许多技术性定理,例如在无限分配律(infinite distributivity)、格的赋值(valuations)、度量格(metric lattices)等方面的结果。</p><p>这些成果进一步推动了抽象射影几何与格论的研究,对后续数学发展产生影响。</p><h3 id="十、数学统计学(Mathematical-statistics)"><a href="#十、数学统计学(Mathematical-statistics)" class="headerlink" title="十、数学统计学(Mathematical statistics)"></a>十、数学统计学(Mathematical statistics)</h3><p>von Neumann 在 1941 年给出了 “对于相互独立、同分布的正态随机变量,其连续差分(successive differences)的平方均值与样本方差之比” 的确切分布。</p><p>该比率后来被应用于回归模型的残差(residuals),并以 Durbin(James Durbin, 1923-2012)-Watson(Geoffrey Stuart Watson, 1921-1998)统计量(Durbin-Watson statistic)之名而广为人知,用于检验回归误差项在原假设下是否相互独立,对比备择假设 “误差项服从平稳的一阶自回归过程”。</p><h3 id="十一、数学其他"><a href="#十一、数学其他" class="headerlink" title="十一、数学其他"></a>十一、数学其他</h3><p>von Neumann 在数学上还证明了很多没有被上述的归类提到的工作,比如他证明了对于<mjx-container class="MathJax" jax="SVG" overflow="overflow"><svg style="vertical-align:-.566ex" xmlns="http://www.w3.org/2000/svg" width="1.02ex" height="2.262ex" role="img" focusable="false" viewBox="0 -750 451 1000"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(1,-1)"><g data-mml-node="math" data-latex="r>0"><g data-mml-node="mi" data-latex="r"><path data-c="1D45F" d="M436 374C436 416 395 442 351 442 302 442 261 419 227 372 217 411 183 442 136 442 95 442 65 410 44 345 34 312 29 293 29 287 29 278 34 273 45 273 50 273 53 274 56 276 61 285 64 292 65 299 83 375 106 413 133 413 150 413 159 399 159 371 159 358 154 331 144 290L87 63C84 50 78 24 78 19 78-1 89-11 110-11 130-11 143-1 150 19L169 91C180 134 187 162 190 175L221 303C223 311 231 324 244 343 271 381 302 413 351 413 363 413 373 411 382 406 352 397 337 378 337 351 337 325 351 312 378 312 411 312 436 341 436 374Z"></path></g></g></g></svg><mjx-break size="4"></mjx-break><svg style="vertical-align:-.566ex" xmlns="http://www.w3.org/2000/svg" width="3.52ex" height="2.262ex" role="img" focusable="false" viewBox="0 -750 1555.8 1000"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(1,-1)"><g data-mml-node="math" data-latex="r>0"><g data-mml-node="mo" data-latex=">"><path data-c="3E" d="M686 227C696 232 701 239 701 250 701 261 696 268 686 273L112 545C109 546 105 547 101 547 85 547 77 539 77 522 77 513 82 506 91 502L625 250 91-2C82-6 77-13 77-22 77-39 85-47 101-47 105-47 109-46 112-45Z"></path></g><g data-mml-node="mn" data-latex="0" transform="translate(1055.8,0)"><path data-c="30" d="M249-22C390-22 460 92 460 320 460 473 428 575 365 625 330 652 291 666 250 666 109 666 39 551 39 320 39 136 88-22 249-22M361 524C368 489 371 425 371 332 371 240 367 172 360 128 347 48 310 8 249 8 226 8 203 17 182 34 155 57 139 104 132 176 129 201 128 253 128 332 128 419 131 480 136 513 145 568 163 603 191 618 213 630 232 636 249 636 314 636 350 583 361 524Z"></path></g></g></g></svg></mjx-container> ,</p><p><mjx-container class="MathJax" jax="SVG" overflow="overflow" display="true" width="full" style="min-width:24.355ex"><svg style="vertical-align:-2.649ex;min-width:24.355ex" xmlns="http://www.w3.org/2000/svg" width="100%" height="6.429ex" role="img" focusable="false"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(0.0181,-0.0181) translate(0, -1670.7)"><g data-mml-node="math" data-latex="A_r = \sum_{n\ge0} \frac{2^{2[nr] } }{2^{2n^2} }"><g data-mml-node="mtable" data-latex="A_r = \sum_{n\ge0} \frac{2^{2[nr] } }{2^{2n^2} }" transform="translate(2078,0) translate(-2078,0)"><g transform="translate(0 1670.7) matrix(1 0 0 -1 0 0) scale(55.25)"><svg data-table="true" preserveAspectRatio="xMidYMid" viewBox="3304.5 -1670.7 1 2841.4"><g transform="matrix(1 0 0 -1 0 0)"><g data-mml-node="mlabeledtr" transform="translate(0,101.4)"><g data-mml-node="mtd"><g data-mml-node="msub" data-latex="A_r"><g data-mml-node="mi" data-latex="A"><path data-c="1D434" d="M137 3C155 3 217 0 236 0 251 0 258 8 258 23 258 32 252 38 239 39 210 40 196 50 196 69 196 78 205 98 224 128 251 173 270 206 283 228L526 228C526 221 527 207 530 185 537 112 541 72 541 67 541 48 519 39 474 39 455 39 446 31 446 15 446 5 452 0 464 0 488 0 564 3 588 3 608 3 679 0 699 0 714 0 721 8 721 24 721 34 712 39 694 39 666 39 649 41 644 44 639 47 635 56 634 71L574 689C571 708 572 716 551 716 539 716 529 710 522 697L178 120C148 70 108 43 59 39 43 38 35 30 35 15 35 5 41 0 52 0 68 0 121 3 137 3M492 577 522 267 307 267Z"></path></g><g data-mml-node="mi" transform="translate(783,-150) scale(0.707)" data-latex="r"><path data-c="1D45F" d="M436 374C436 416 395 442 351 442 302 442 261 419 227 372 217 411 183 442 136 442 95 442 65 410 44 345 34 312 29 293 29 287 29 278 34 273 45 273 50 273 53 274 56 276 61 285 64 292 65 299 83 375 106 413 133 413 150 413 159 399 159 371 159 358 154 331 144 290L87 63C84 50 78 24 78 19 78-1 89-11 110-11 130-11 143-1 150 19L169 91C180 134 187 162 190 175L221 303C223 311 231 324 244 343 271 381 302 413 351 413 363 413 373 411 382 406 352 397 337 378 337 351 337 325 351 312 378 312 411 312 436 341 436 374Z"></path></g></g><g data-mml-node="mo" data-latex="=" transform="translate(1429.7,0)"><path data-c="3D" d="M698 367 80 367C64 367 56 359 56 344 56 329 64 321 80 321L698 321C714 321 722 329 722 344 722 356 711 367 698 367M698 179 80 179C64 179 56 171 56 156 56 141 64 133 80 133L698 133C714 133 722 141 722 156 722 169 711 179 698 179Z"></path></g><g data-mml-node="munder" data-latex="\sum_{n\ge0}" transform="translate(2485.5,0)"><g data-mml-node="mo" data-latex="\sum"><path data-c="2211" d="M1265-450 1389-124 1355-124C1336-174 1304-216 1258-250 1145-334 1000-356 791-356L200-356 700 232C707 239 710 246 710 251L244 894 781 894C970 894 1127 870 1230 804 1290 766 1332 719 1356 663L1389 663 1265 950 88 950C70 950 60 947 57 941 56 938 56 926 56 905L581 187 68-415C61-423 57-430 57-435 57-445 67-450 88-450Z"></path></g><g data-mml-node="TeXAtom" transform="translate(58,-1087.9) scale(0.707)" data-latex="{n\ge0}" data-mjx-texclass="ORD"><g data-mml-node="mi" data-latex="n"><path data-c="1D45B" d="M537 137C514 58 481 18 440 18 427 18 420 28 420 47 420 61 426 84 438 115 478 224 498 296 498 333 498 403 451 442 381 442 322 442 271 416 230 363 222 407 187 442 136 442 80 442 58 390 44 345 34 313 29 294 29 287 29 278 34 273 45 273 50 273 53 274 56 276 61 285 64 292 65 299 83 375 106 413 133 413 151 413 160 399 160 371 160 358 155 331 144 290L87 63C84 50 78 24 78 19 78-1 89-11 111-11 130-11 144-1 151 19 153 24 159 49 170 92L191 181 221 295C232 318 249 341 270 365 299 397 335 413 378 413 411 413 427 391 427 348 427 310 406 234 363 120 356 102 353 87 353 74 353 25 390-11 438-11 482-11 517 14 542 64 561 104 571 131 571 144 571 153 566 158 555 158 552 158 537 149 537 137Z"></path></g><g data-mml-node="mo" data-latex="\ge" transform="translate(600,0)"><path data-c="2265" d="M684 310C694 315 699 322 699 333 699 344 694 352 684 357L110 629C107 630 103 631 99 631 83 631 75 623 75 606 75 597 80 590 89 586L623 333 89 80C80 76 75 69 75 60 75 43 83 35 99 35 103 35 107 36 110 38M678-72 100-72C84-72 76-80 76-95 76-111 84-119 100-119L678-119C694-119 702-111 702-95 702-83 691-72 678-72Z"></path></g><g data-mml-node="mn" data-latex="0" transform="translate(1378,0)"><path data-c="30" d="M249-22C390-22 460 92 460 320 460 473 428 575 365 625 330 652 291 666 250 666 109 666 39 551 39 320 39 136 88-22 249-22M361 524C368 489 371 425 371 332 371 240 367 172 360 128 347 48 310 8 249 8 226 8 203 17 182 34 155 57 139 104 132 176 129 201 128 253 128 332 128 419 131 480 136 513 145 568 163 603 191 618 213 630 232 636 249 636 314 636 350 583 361 524Z"></path></g></g></g><g data-mml-node="mfrac" data-latex="\frac{2^{2[nr] } }{2^{2n^2} }" transform="translate(4096.1,0)"><g data-mml-node="msup" data-latex="2^{2[nr] } " transform="translate(220,676)"><g data-mml-node="mn" data-latex="2"><path data-c="32" d="M237 666C186 666 143 648 106 612 69 576 50 534 50 483 50 449 75 424 106 424 136 424 161 450 161 480 161 513 137 536 105 536 102 536 100 536 98 535 117 584 161 627 224 627 306 627 352 556 352 470 352 403 318 331 250 255L62 43C49 28 50 29 50 0L421 0 450 180 417 180C409 129 402 100 396 91 391 86 361 84 306 84L139 84 236 179C304 243 390 312 419 365 439 400 449 435 449 470 449 588 357 666 237 666Z"></path></g><g data-mml-node="TeXAtom" transform="translate(533,363) scale(0.707)" data-latex="{2[n r]}" data-mjx-texclass="ORD"><g data-mml-node="mn" data-latex="2"><path data-c="32" d="M237 666C186 666 143 648 106 612 69 576 50 534 50 483 50 449 75 424 106 424 136 424 161 450 161 480 161 513 137 536 105 536 102 536 100 536 98 535 117 584 161 627 224 627 306 627 352 556 352 470 352 403 318 331 250 255L62 43C49 28 50 29 50 0L421 0 450 180 417 180C409 129 402 100 396 91 391 86 361 84 306 84L139 84 236 179C304 243 390 312 419 365 439 400 449 435 449 470 449 588 357 666 237 666Z"></path></g><g data-mml-node="mo" data-latex="[" transform="translate(500,0)"><path data-c="5B" d="M233-202 159-202 159 702 233 702C248 702 256 710 256 726 256 742 248 750 233 750L114 750 114-250 233-250C248-250 256-242 256-226 256-214 245-202 233-202Z"></path></g><g data-mml-node="mi" data-latex="n" transform="translate(778,0)"><path data-c="1D45B" d="M537 137C514 58 481 18 440 18 427 18 420 28 420 47 420 61 426 84 438 115 478 224 498 296 498 333 498 403 451 442 381 442 322 442 271 416 230 363 222 407 187 442 136 442 80 442 58 390 44 345 34 313 29 294 29 287 29 278 34 273 45 273 50 273 53 274 56 276 61 285 64 292 65 299 83 375 106 413 133 413 151 413 160 399 160 371 160 358 155 331 144 290L87 63C84 50 78 24 78 19 78-1 89-11 111-11 130-11 144-1 151 19 153 24 159 49 170 92L191 181 221 295C232 318 249 341 270 365 299 397 335 413 378 413 411 413 427 391 427 348 427 310 406 234 363 120 356 102 353 87 353 74 353 25 390-11 438-11 482-11 517 14 542 64 561 104 571 131 571 144 571 153 566 158 555 158 552 158 537 149 537 137Z"></path></g><g data-mml-node="mi" data-latex="r" transform="translate(1378,0)"><path data-c="1D45F" d="M436 374C436 416 395 442 351 442 302 442 261 419 227 372 217 411 183 442 136 442 95 442 65 410 44 345 34 312 29 293 29 287 29 278 34 273 45 273 50 273 53 274 56 276 61 285 64 292 65 299 83 375 106 413 133 413 150 413 159 399 159 371 159 358 154 331 144 290L87 63C84 50 78 24 78 19 78-1 89-11 110-11 130-11 143-1 150 19L169 91C180 134 187 162 190 175L221 303C223 311 231 324 244 343 271 381 302 413 351 413 363 413 373 411 382 406 352 397 337 378 337 351 337 325 351 312 378 312 411 312 436 341 436 374Z"></path></g><g data-mml-node="mo" data-latex="]" transform="translate(1829,0)"><path data-c="5D" d="M45-250 164-250 164 750 45 750C30 750 22 742 22 726 22 710 30 702 45 702L119 702 119-202 45-202C30-202 22-210 22-226 22-242 30-250 45-250Z"></path></g></g></g><g data-mml-node="msup" data-latex="2^{2n^2 } " transform="translate(421.7,-786.4)"><g data-mml-node="mn" data-latex="2"><path data-c="32" d="M237 666C186 666 143 648 106 612 69 576 50 534 50 483 50 449 75 424 106 424 136 424 161 450 161 480 161 513 137 536 105 536 102 536 100 536 98 535 117 584 161 627 224 627 306 627 352 556 352 470 352 403 318 331 250 255L62 43C49 28 50 29 50 0L421 0 450 180 417 180C409 129 402 100 396 91 391 86 361 84 306 84L139 84 236 179C304 243 390 312 419 365 439 400 449 435 449 470 449 588 357 666 237 666Z"></path></g><g data-mml-node="TeXAtom" transform="translate(533,289) scale(0.707)" data-latex="{2n^2}" data-mjx-texclass="ORD"><g data-mml-node="mn" data-latex="2"><path data-c="32" d="M237 666C186 666 143 648 106 612 69 576 50 534 50 483 50 449 75 424 106 424 136 424 161 450 161 480 161 513 137 536 105 536 102 536 100 536 98 535 117 584 161 627 224 627 306 627 352 556 352 470 352 403 318 331 250 255L62 43C49 28 50 29 50 0L421 0 450 180 417 180C409 129 402 100 396 91 391 86 361 84 306 84L139 84 236 179C304 243 390 312 419 365 439 400 449 435 449 470 449 588 357 666 237 666Z"></path></g><g data-mml-node="msup" data-latex="n^2" transform="translate(500,0)"><g data-mml-node="mi" data-latex="n"><path data-c="1D45B" d="M537 137C514 58 481 18 440 18 427 18 420 28 420 47 420 61 426 84 438 115 478 224 498 296 498 333 498 403 451 442 381 442 322 442 271 416 230 363 222 407 187 442 136 442 80 442 58 390 44 345 34 313 29 294 29 287 29 278 34 273 45 273 50 273 53 274 56 276 61 285 64 292 65 299 83 375 106 413 133 413 151 413 160 399 160 371 160 358 155 331 144 290L87 63C84 50 78 24 78 19 78-1 89-11 111-11 130-11 144-1 151 19 153 24 159 49 170 92L191 181 221 295C232 318 249 341 270 365 299 397 335 413 378 413 411 413 427 391 427 348 427 310 406 234 363 120 356 102 353 87 353 74 353 25 390-11 438-11 482-11 517 14 542 64 561 104 571 131 571 144 571 153 566 158 555 158 552 158 537 149 537 137Z"></path></g><g data-mml-node="mn" transform="translate(633,289) scale(0.707)" data-latex="2"><path data-c="32" d="M237 666C186 666 143 648 106 612 69 576 50 534 50 483 50 449 75 424 106 424 136 424 161 450 161 480 161 513 137 536 105 536 102 536 100 536 98 535 117 584 161 627 224 627 306 627 352 556 352 470 352 403 318 331 250 255L62 43C49 28 50 29 50 0L421 0 450 180 417 180C409 129 402 100 396 91 391 86 361 84 306 84L139 84 236 179C304 243 390 312 419 365 439 400 449 435 449 470 449 588 357 666 237 666Z"></path></g></g></g></g><rect width="2272.9" height="60" x="120" y="220"></rect></g></g></g></g></svg><svg data-labels="true" preserveAspectRatio="xMaxYMid" viewBox="1278 -1670.7 1 2841.4"><g data-labels="true" transform="matrix(1 0 0 -1 0 0)"><g data-mml-node="mtd" id="mjx-eqn:2" transform="translate(0,849.4)"><text data-id-align="true"></text><g data-idbox="true" transform="translate(0,-748)"><g data-mml-node="mtext" data-latex="\text{(2)}"><path data-c="28" d="M318-248C327-248 332-243 332-234 332-231 330-227 327-223 275-183 233-117 202-26 175 53 161 131 161 208L161 292C161 369 175 447 202 526 233 617 275 683 327 723 330 726 332 730 332 734 332 743 327 748 318 748 317 748 314 747 311 745 251 699 201 631 160 540 121 453 101 371 101 292L101 208C101 129 121 47 160-40 201-131 251-199 311-245 314-247 317-248 318-248Z"></path><path data-c="32" d="M237 666C186 666 143 648 106 612 69 576 50 534 50 483 50 449 75 424 106 424 136 424 161 450 161 480 161 513 137 536 105 536 102 536 100 536 98 535 117 584 161 627 224 627 306 627 352 556 352 470 352 403 318 331 250 255L62 43C49 28 50 29 50 0L421 0 450 180 417 180C409 129 402 100 396 91 391 86 361 84 306 84L139 84 236 179C304 243 390 312 419 365 439 400 449 435 449 470 449 588 357 666 237 666Z" transform="translate(389,0)"></path><path data-c="29" d="M78-245C138-199 188-131 229-40 268 47 288 129 288 208L288 292C288 371 268 453 229 540 188 631 138 699 78 745 75 747 72 748 71 748 62 748 57 743 57 734 57 730 59 726 62 723 114 683 156 617 187 526 214 447 228 369 228 292L228 208C228 131 214 53 187-26 156-117 114-183 62-223 59-227 57-231 57-234 57-243 62-248 71-248 72-248 75-247 78-245Z" transform="translate(889,0)"></path></g></g></g></g></svg></g></g></g></g></svg></mjx-container></p><p>是代数无关的(algebraically independent)。</p><h3 id="十二、物理学"><a href="#十二、物理学" class="headerlink" title="十二、物理学"></a>十二、物理学</h3><p>John von Neumann 在 1932 年出版的《量子力学的数学基础》(Mathematical Foundations of Quantum Mechanics)中,以 “von Neumann 公理体系” 的形式,尝试为量子力学建立数学基础,系统地将量子态视为希尔伯特空间中的点,并用线性算子来表示可观测量(observable),从而把量子物理问题化约为对无穷维希尔伯特空间及其算子的研究。</p><p>这种数学形式同时包含了海森堡(Werner Karl Heisenberg, 1901-1976)与薛定谔(Erwin Rudolf Josef Alexander Schrödinger, 1887-1961)的各自表述,并清晰刻画了算子不对易所对应的不确定性原理(uncertainty principle)。</p><p>在研究量子测量(quantum measurement)时,John von Neumann 认为必须有 “观察者(observer)” 来引发波函数坍缩(wave function collapse),甚至把意识视为潜在的坍缩根源,该观点后来形成了 “John von Neumann-Eugene Wigner 诠释(von Neumann-Wigner interpretation)”,虽曾得到 Eugene Wigner 的支持,但并未成为主流。</p><p>在对量子理论基础的探讨中,John von Neumann 试图证明量子力学的统计结果无法被某种潜在的 “隐变量(hidden variable)” 理论所解释,引发了后来的格蕾特・赫尔曼(Grete Hermann, 1901-1984)、约翰・斯图尔特・贝尔(John Stewart Bell, 1928-1990)等人的批评与修正。</p><p>尽管他的证明并不适用于排除所有类型的隐变量理论,但推动了后续格里森(Andrew Mattei Gleason, 1921-2008)定理(Gleason's theorem)、贝尔定理(Bell's theorem)以及阿斯派克(Alain Aspect, 1947-,2022 年诺贝尔物理学奖得主)的实验等研究,最终在非定域性(nonlocality)、量子现实观以及与狭义相对论(special relativity)的兼容问题上产生深远影响。</p><p>John von Neumann 在量子信息论(quantum information theory)领域也具有奠基性地位,他提出的 “冯・诺依曼熵(von Neumann entropy)”</p><p><mjx-container class="MathJax" jax="SVG" overflow="overflow" display="true" width="full" style="min-width:24.147ex"><svg style="vertical-align:-.566ex;min-width:24.147ex" xmlns="http://www.w3.org/2000/svg" width="100%" height="2.262ex" role="img" focusable="false"><g stroke="currentColor" fill="currentColor" stroke-width="0" transform="scale(0.0181,-0.0181) translate(0, -750)"><g data-mml-node="math" data-latex="S = -\text{tr}(\rho \ln \rho)"><g data-mml-node="mtable" data-latex="S = -\text{tr}(\rho \ln \rho)" transform="translate(2078,0) translate(-2078,0)"><g transform="translate(0 750) matrix(1 0 0 -1 0 0) scale(55.25)"><svg data-table="true" preserveAspectRatio="xMidYMid" viewBox="3258.4 -750 1 1000"><g transform="matrix(1 0 0 -1 0 0)"><g data-mml-node="mlabeledtr"><g data-mml-node="mtd"><g data-mml-node="mi" data-latex="S"><path data-c="1D446" d="M133 157C133 181 136 201 141 217 141 227 136 232 125 232 120 232 116 230 114 228 109 223 52 8 52-8 52-17 57-22 67-22 72-22 79-17 88-6L133 47C168 1 224-22 300-22 366-22 424 5 476 58 528 111 554 170 554 236 554 283 538 323 505 355 490 368 470 379 445 388 422 393 400 399 378 405L312 423C279 432 254 469 254 509 254 552 271 589 306 621 341 653 380 669 423 669 515 669 561 619 561 520 561 502 557 482 557 465L557 462C560 455 565 451 573 451 582 451 588 459 592 474L645 691C645 700 640 705 630 705 625 705 618 700 609 689L566 637C538 682 491 705 424 705 361 705 304 681 254 634 202 586 176 531 176 468 176 396 223 339 282 323L387 296C441 281 475 262 475 195 475 149 457 108 422 72 387 36 347 17 302 17 204 17 133 60 133 157Z"></path></g><g data-mml-node="mo" data-latex="=" transform="translate(922.8,0)"><path data-c="3D" d="M698 367 80 367C64 367 56 359 56 344 56 329 64 321 80 321L698 321C714 321 722 329 722 344 722 356 711 367 698 367M698 179 80 179C64 179 56 171 56 156 56 141 64 133 80 133L698 133C714 133 722 141 722 156 722 169 711 179 698 179Z"></path></g><g data-mml-node="mo" data-latex="-" transform="translate(1978.6,0)"><path data-c="2212" d="M698 270 80 270C64 270 56 263 56 250 56 237 64 230 80 230L698 230C714 230 722 237 722 250 722 262 710 270 698 270Z"></path></g><g data-mml-node="mtext" data-latex="\text{tr}" transform="translate(2756.6,0)"><path data-c="74" d="M332 126 332 186 300 186 300 128C300 78 282 22 238 22 197 22 177 56 177 124L177 395 316 395 316 433 177 433 177 615 145 615C144 582 141 553 134 527 117 461 78 427 19 424L19 395 102 395 102 126C102 67 120 29 155 10 182-4 207-11 232-11 298-11 332 55 332 126Z"></path><path data-c="72" d="M364 378C364 417 327 442 288 442 237 442 198 412 172 351L172 442 28 431 28 393C63 393 84 390 92 384 100 378 104 365 104 342L104 79C104 60 101 48 94 44 87 40 65 38 28 38L28 0 143 3C185 4 228 3 271 0L271 38 247 38C214 38 193 41 186 46 179 51 176 63 176 81L176 232C176 275 184 314 199 347 219 390 248 412 287 413 277 403 272 391 272 377 272 346 287 331 318 331 345 331 364 352 364 378Z" transform="translate(389,0)"></path></g><g data-mml-node="mo" data-latex="(" transform="translate(3537.6,0)"><path data-c="28" d="M318-248C327-248 332-243 332-234 332-231 330-227 327-223 275-183 233-117 202-26 175 53 161 131 161 208L161 292C161 369 175 447 202 526 233 617 275 683 327 723 330 726 332 730 332 734 332 743 327 748 318 748 317 748 314 747 311 745 251 699 201 631 160 540 121 453 101 371 101 292L101 208C101 129 121 47 160-40 201-131 251-199 311-245 314-247 317-248 318-248Z"></path></g><g data-mml-node="mi" data-latex="\rho" transform="translate(3926.6,0)"><path data-c="1D70C" d="M361 442C248 442 154 320 129 220L33-169C31-177 30-182 30-185 30-206 40-216 61-216 76-216 89-208 99-193L160 46C183 7 215-13 256-13 322-13 380 19 431 84 478 145 502 210 502 277 502 368 449 442 361 442M359 412C402 412 423 381 423 319 423 292 417 257 406 212 384 127 353 70 314 40 293 24 274 16 255 16 236 16 219 23 206 36 185 57 175 79 175 100 176 107 178 119 182 136 205 231 225 292 241 320 276 381 315 412 359 412Z"></path></g><g data-mml-node="mi" data-latex="\ln" transform="translate(4610.2,0)"><path data-c="6C" d="M144 3 255 0 255 39C219 39 197 40 190 44 183 48 180 60 180 79L180 694 33 683 33 645C68 645 90 642 97 636 104 630 108 616 108 593L108 79C108 60 105 48 98 44 91 40 69 39 33 39L33 0Z"></path><path data-c="6E" d="M314 413C359 413 382 378 382 307L382 79C382 60 379 48 372 44 365 40 343 38 306 38L306 0 421 3 535 0 535 38C503 38 482 39 472 42 462 45 458 52 458 64L458 251C458 298 457 331 454 350 444 411 399 442 320 442 257 442 210 412 179 352L179 442 32 431 32 393C68 393 90 390 98 384 106 378 109 365 109 342L109 79C109 60 105 48 98 44 91 40 69 38 32 38L32 0 147 3 261 0 261 38C224 38 203 40 196 44 189 48 185 60 185 79L185 259C185 340 236 413 314 413Z" transform="translate(278,0)"></path></g><g data-mml-node="mo" transform="translate(5444.2,0)"><path data-c="2061" d=""></path></g><g data-mml-node="mi" data-latex="\rho" transform="translate(5610.9,0)"><path data-c="1D70C" d="M361 442C248 442 154 320 129 220L33-169C31-177 30-182 30-185 30-206 40-216 61-216 76-216 89-208 99-193L160 46C183 7 215-13 256-13 322-13 380 19 431 84 478 145 502 210 502 277 502 368 449 442 361 442M359 412C402 412 423 381 423 319 423 292 417 257 406 212 384 127 353 70 314 40 293 24 274 16 255 16 236 16 219 23 206 36 185 57 175 79 175 100 176 107 178 119 182 136 205 231 225 292 241 320 276 381 315 412 359 412Z"></path></g><g data-mml-node="mo" data-latex=")" transform="translate(6127.9,0)"><path data-c="29" d="M78-245C138-199 188-131 229-40 268 47 288 129 288 208L288 292C288 371 268 453 229 540 188 631 138 699 78 745 75 747 72 748 71 748 62 748 57 743 57 734 57 730 59 726 62 723 114 683 156 617 187 526 214 447 228 369 228 292L228 208C228 131 214 53 187-26 156-117 114-183 62-223 59-227 57-231 57-234 57-243 62-248 71-248 72-248 75-247 78-245Z"></path></g></g></g></g></svg><svg data-labels="true" preserveAspectRatio="xMaxYMid" viewBox="1278 -750 1 1000"><g data-labels="true" transform="matrix(1 0 0 -1 0 0)"><g data-mml-node="mtd" id="mjx-eqn:3"><g data-mml-node="mtext" data-latex="\text{(3)}"><path data-c="28" d="M318-248C327-248 332-243 332-234 332-231 330-227 327-223 275-183 233-117 202-26 175 53 161 131 161 208L161 292C161 369 175 447 202 526 233 617 275 683 327 723 330 726 332 730 332 734 332 743 327 748 318 748 317 748 314 747 311 745 251 699 201 631 160 540 121 453 101 371 101 292L101 208C101 129 121 47 160-40 201-131 251-199 311-245 314-247 317-248 318-248Z"></path><path data-c="33" d="M303 353C369 378 431 441 431 526 431 569 410 604 369 631 333 654 292 666 246 666 201 666 162 654 127 631 88 605 68 571 68 528 68 495 90 472 122 472 154 472 176 495 176 527 176 560 157 578 119 580 145 615 186 633 242 633 302 633 332 598 332 527 332 485 324 450 309 421 282 373 245 364 183 364 171 362 165 357 165 348 165 333 172 333 192 333L235 333C310 333 348 280 348 173 348 88 317 14 241 14 176 14 128 36 99 80 134 79 160 105 160 139 160 173 135 198 101 198 62 198 42 178 42 137 42 88 64 49 108 18 147-9 193-22 244-22 301-22 350-3 393 34 436 71 457 117 457 173 457 267 383 332 303 353Z" transform="translate(389,0)"></path><path data-c="29" d="M78-245C138-199 188-131 229-40 268 47 288 129 288 208L288 292C288 371 268 453 229 540 188 631 138 699 78 745 75 747 72 748 71 748 62 748 57 743 57 734 57 730 59 726 62 723 114 683 156 617 187 526 214 447 228 369 228 292L228 208C228 131 214 53 187-26 156-117 114-183 62-223 59-227 57-231 57-234 57-243 62-248 71-248 72-248 75-247 78-245Z" transform="translate(889,0)"></path></g></g></g></svg></g></g></g></g></svg></mjx-container></p><p>为描述量子状态的信息量提供了关键指标,并帮助定义如霍勒沃(Alexander Semenovich Holevo, 1943- )熵(Holevo entropy)、条件量子熵(conditional quantum entropy)等广义熵度量,在量子纠缠、量子通等研究中具有核心地位。</p><p>此外,他在 1927 年首次引入 “密度矩阵(density matrix)” 形式,能同时刻画纯态(pure state)与混合态(mixed state),为后来的量子退相干(quantum decoherence)、量子测量方案(quantum measurement scheme)奠定理论基础。</p><p>在量子逻辑(quantum logic)方面,von Neumann 与加勒特・伯克霍夫(Garrett Birkhoff, 1911-1996)共同发展出了一种区别于经典逻辑的 “量子逻辑” 体系,揭示了量子力学中非分配性(non-distributivity)与非对易性(non-commutativity)的深层结构;而在 “von Neumann 测量方案” 中,他提出将测量装置本身也视作量子系统,并引入投影测量的形式化表达,为日后量子退相干理论(quantum decoherence theory)铺平道路。</p><p>除量子领域外,John von Neumann 在流体力学(fluid dynamics)中同样成果卓著,包括对爆轰波(detonation wave)模型(ZND 模型)的阐明、对成形装药(shaped charge)的数值研究,以及与里希特迈尔(Robert Davis Richtmyer, 1910-2003)共同提出 “人工黏性” 算法来模拟激波(shock wave),从而在计算流体力学和弹道学方面大显身手。</p><p>他的研究不仅在理论上持续影响着对量子力学本质及测量问题的讨论,也实质推动了现代计算物理(computational physics)、信息论(information theory)和数理逻辑(mathematical logic)的发展,被公认为近代最具影响力的数学物理学家之一。</p><h3 id="十三、计算机"><a href="#十三、计算机" class="headerlink" title="十三、计算机"></a>十三、计算机</h3><p>von Neumann 是计算机领域的奠基性人物之一,他不仅在硬件设计上留下重要贡献(如对 ENIAC 的咨询、撰写未完成的 EDVAC 报告,并设计了 IAS 机器),也因在同一存储器中存放指令与数据的 “von Neumann 结构”(von Neumann architecture)而闻名。</p><p>他提出了 “归并排序(merge sort)” 算法,与斯坦尼斯拉夫・乌拉姆(Stanisław Ulam)等人共同发展了蒙特卡洛方法(Monte Carlo method),并设计了利用有偏硬币来模拟公平硬币的算法以及 “中平方法(middle-square method)” 这种早期的伪随机数生成方式。</p><p>此外,von Neumann 在随机计算(stochastic computing)和计算复杂性(computational complexity)的早期研究中也有先驱性贡献;他设计的 “自复制通用构造器(universal constructor)” 及对元胞自动机(cellular automata)的研究,为后来生物系统与人工生命的模拟奠定了理论基础。</p><p>在科学计算与数值分析方面,他提出了著名的 “von Neumann 稳定性分析(von Neumann stability analysis)”,并率先将计算机用于求解非线性偏微分方程,开创了以数值方法研究爆炸、流体力学等复杂问题的新途径。他还领导了早期的数值天气预报(numerical weather prediction)研究,组建团队利用 ENIAC 首次实现了大气环流模拟,并预见了燃烧化石燃料所导致的温室效应和全球变暖趋势。</p><p>von Neumann 在气象学、气候学等领域同样发挥了领军作用,对如何通过操作地球环境(例如在极地冰盖上施加吸热物质)进行气候干预也提出了开创性的设想。他在 20 世纪 50 年代还讨论过技术发展加速所导致的人类社会 “奇点(singularity)” 问题,认为技术突飞猛进可能会带来超越以往认知的重大变革。</p><p>可以说,von Neumann 在计算、数值模拟以及前瞻性技术思考等多方面都深刻地影响了现代科学与工程的发展。</p><h3 id="十四、经济学"><a href="#十四、经济学" class="headerlink" title="十四、经济学"></a>十四、经济学</h3><p>von Neumann 奠定了博弈论(Game Theory)的数学基础,最初在 1928 年证明了 “极小极大定理(minimax theorem)”,说明在零和博弈(zero-sum game)且信息完备(perfect information)的条件下,两位参与者都存在可以最小化其最大损失的最优策略。</p><p>这一成果在他与奥斯卡・摩根斯坦(Oskar Morgenstern, 1902-1977)于 1944 年合著的《博弈论与经济行为》(Theory of Games and Economic Behavior)中得到进一步推广,包括对不完美信息(imperfect information)以及多方参与的博弈情况的讨论。von Neumann 在书中指出,经济学研究应当更多借助泛函分析,尤其是凸集和拓扑不动点定理,而非传统的微分方法。</p><p>在数学经济学中,von Neumann 通过构造经济增长模型(expanding economy)并运用布劳尔不动点定理(Brouwer fixed-point theorem)等工具,证明了该模型的平衡解既存在又唯一。他的模型将非负矩阵与概率向量相结合,给出了经济增长率以及利率的数学表达方式,后来被视作线性规划(Linear Programming)的特例。</p><p>该研究也对日后经济学中的凸分析、线性不等式与鞍点对偶性等方法具有奠基意义。</p></div></div><div class="footer"></div><div class="article-meta" id="bottom"><div class="new-meta-box"></div></div><div class="prev-next"><a class="prev" href="/notes/person/13"><p class="title"><i class="fa-solid fa-chevron-left" aria-hidden="true"></i>Littlewood英国数学家李特尔伍德生平与数学贡献</p><p class="content">约翰·埃德森·李特尔伍德是英国数学家,以其与哈代的长期合作闻名。他们在解析数论、函数论等领域取得开创性成果,如关于素数定理误差项的研究及著名的Hardy-Littlewood猜想。他一生深受抑郁症困扰,但学术成就卓著</p></a><a class="next" href="/notes/person/15"><p class="title">Irving Segal欧文·西格尔:联结算子代数与宇宙学的数学物理学家<i class="fa-solid fa-chevron-right" aria-hidden="true"></i></p><p class="content">欧文·西格尔是20世纪重要的数学物理学家。他奠定了C代数的基础并提出了GNS构造,致力于为量子力学建立严格的数学公理化体系。其学术生涯后期转向宇宙学研究,提出了与大爆炸理论相悖的计时宇宙学模型</p></a></div><div class="recommended-article"><div class="recommended-article-header"><i class="fa-solid fa-bookmark fa-fw" aria-hidden="true"></i> <span>推荐阅读</span></div><div class="recommended-article-group"> <a class="recommended-article-item" href="/notes/person/15.html" title="Irving Segal欧文·西格尔:联结算子代数与宇宙学的数学物理学家" rel="bookmark"><img src="https://static.mhuig.top/npm/imbox@0.0.15/c/43.webp" class="lazyload" data-srcset="https://static.mhuig.top/npm/imbox@0.0.15/c/43.webp" srcset="data:image/gif;base64,R0lGODlhAQABAIAAAP///////yH5BAEKAAEALAAAAAABAAEAAAICTAEAOw==" alt="Irving Segal欧文·西格尔:联结算子代数与宇宙学的数学物理学家"> <span class="title">Irving Segal欧文·西格尔:联结算子代数与宇宙学的数学物理学家</span></a> <a class="recommended-article-item" href="/notes/person/1.html" title="希尔伯特23问题" rel="bookmark"><img src="https://static.mhuig.top/npm/imbox@0.0.15/c/109.webp" class="lazyload" data-srcset="https://static.mhuig.top/npm/imbox@0.0.15/c/109.webp" srcset="data:image/gif;base64,R0lGODlhAQABAIAAAP///////yH5BAEKAAEALAAAAAABAAEAAAICTAEAOw==" alt="希尔伯特23问题"> <span class="title">希尔伯特23问题</span></a> <a class="recommended-article-item" href="/notes/person/16.html" title="Birkhoff乔治·大卫·伯克霍夫:美国数学巨擘与美学探路者" rel="bookmark"><img src="https://static.mhuig.top/npm/imbox@0.0.15/c/116.webp" class="lazyload" data-srcset="https://static.mhuig.top/npm/imbox@0.0.15/c/116.webp" srcset="data:image/gif;base64,R0lGODlhAQABAIAAAP///////yH5BAEKAAEALAAAAAABAAEAAAICTAEAOw==" alt="Birkhoff乔治·大卫·伯克霍夫:美国数学巨擘与美学探路者"> <span class="title">Birkhoff乔治·大卫·伯克霍夫:美国数学巨擘与美学探路者</span></a> <a class="recommended-article-item" href="/notes/person/28.html" title="Grothendieck格罗腾迪克:改变现代数学的概念革新者与人生探索者" rel="bookmark"><img src="https://static.mhuig.top/npm/imbox@0.0.15/c/112.webp" class="lazyload" data-srcset="https://static.mhuig.top/npm/imbox@0.0.15/c/112.webp" srcset="data:image/gif;base64,R0lGODlhAQABAIAAAP///////yH5BAEKAAEALAAAAAABAAEAAAICTAEAOw==" alt="Grothendieck格罗腾迪克:改变现代数学的概念革新者与人生探索者"> <span class="title">Grothendieck格罗腾迪克:改变现代数学的概念革新者与人生探索者</span></a> <a class="recommended-article-item" href="/notes/person/13.html" title="Littlewood英国数学家李特尔伍德生平与数学贡献" rel="bookmark"><img src="https://static.mhuig.top/npm/imbox@0.0.15/c/23.webp" class="lazyload" data-srcset="https://static.mhuig.top/npm/imbox@0.0.15/c/23.webp" srcset="data:image/gif;base64,R0lGODlhAQABAIAAAP///////yH5BAEKAAEALAAAAAABAAEAAAICTAEAOw==" alt="Littlewood英国数学家李特尔伍德生平与数学贡献"> <span class="title">Littlewood英国数学家李特尔伍德生平与数学贡献</span></a> <a class="recommended-article-item" href="/notes/person/27.html" title="Singer辛格:指标定理与数学物理融合的巨人" rel="bookmark"><img src="https://static.mhuig.top/npm/imbox@0.0.15/c/73.webp" class="lazyload" data-srcset="https://static.mhuig.top/npm/imbox@0.0.15/c/73.webp" srcset="data:image/gif;base64,R0lGODlhAQABAIAAAP///////yH5BAEKAAEALAAAAAABAAEAAAICTAEAOw==" alt="Singer辛格:指标定理与数学物理融合的巨人"> <span class="title">Singer辛格:指标定理与数学物理融合的巨人</span></a></div></div></article><article class="post white-box shadow floatable blur" id="comments"><span hidden=""><meta itemprop="discussionUrl" content="/notes/person/14#comments"></span><p ct=""><i class="fa-duotone fa-comments"></i> 留言区</p><div id="layoutHelper-comments"></div></article></div><aside id="l_side" itemscope="" itemtype="http://schema.org/WPSideBar"><section class="widget text desktop mobile pjax"><header><a href="/notes/"><i class="fa-duotone fa-book fa-fw" aria-hidden="true"></i> <span class="name">Notes</span></a></header><div class="content"></div></section><section class="widget list group desktop mobile pjax"><header><i class="fa-duotone fa-p fa-fw" aria-hidden="true"></i> <span class="name">History of mathematics</span></header><div class="content"><ul class="list entry navigation"><li><a class="flat-box" title="/notes/person/" href="/notes/person/" active-action="action-notesperson"><div class="name"> Welcome</div></a></li><li><a class="flat-box" title="/notes/person/1" href="/notes/person/1" active-action="action-notesperson1"><div class="name"> Hilbert</div></a></li><li><a class="flat-box" title="/notes/person/2" href="/notes/person/2" active-action="action-notesperson2"><div class="name"> Thompson</div></a></li><li><a class="flat-box" title="/notes/person/3" href="/notes/person/3" active-action="action-notesperson3"><div class="name"> Conway</div></a></li><li><a class="flat-box" title="/notes/person/4" href="/notes/person/4" active-action="action-notesperson4"><div class="name"> Borcherds</div></a></li><li><a class="flat-box" title="/notes/person/5" href="/notes/person/5" active-action="action-notesperson5"><div class="name"> Wall</div></a></li><li><a class="flat-box" title="/notes/person/6" href="/notes/person/6" active-action="action-notesperson6"><div class="name"> Waldhausen</div></a></li><li><a class="flat-box" title="/notes/person/7" href="/notes/person/7" active-action="action-notesperson7"><div class="name"> Dehn</div></a></li><li><a class="flat-box" title="/notes/person/8" href="/notes/person/8" active-action="action-notesperson8"><div class="name"> Whitehead</div></a></li><li><a class="flat-box" title="/notes/person/9" href="/notes/person/9" active-action="action-notesperson9"><div class="name"> Iwaniec</div></a></li><li><a class="flat-box" title="/notes/person/10" href="/notes/person/10" active-action="action-notesperson10"><div class="name"> Sarnak</div></a></li><li><a class="flat-box" title="/notes/person/11" href="/notes/person/11" active-action="action-notesperson11"><div class="name"> Ramanujan</div></a></li><li><a class="flat-box" title="/notes/person/12" href="/notes/person/12" active-action="action-notesperson12"><div class="name"> Hardy</div></a></li><li><a class="flat-box" title="/notes/person/13" href="/notes/person/13" active-action="action-notesperson13"><div class="name"> Littlewood</div></a></li><li><a class="flat-box" title="/notes/person/14" href="/notes/person/14" active-action="action-notesperson14"><div class="name"> von Neumann</div></a></li><li><a class="flat-box" title="/notes/person/15" href="/notes/person/15" active-action="action-notesperson15"><div class="name"> Irving Segal</div></a></li><li><a class="flat-box" title="/notes/person/16" href="/notes/person/16" active-action="action-notesperson16"><div class="name"> Birkhoff</div></a></li><li><a class="flat-box" title="/notes/person/17" href="/notes/person/17" active-action="action-notesperson17"><div class="name"> Wiener</div></a></li><li><a class="flat-box" title="/notes/person/18" href="/notes/person/18" active-action="action-notesperson18"><div class="name"> Shannon</div></a></li><li><a class="flat-box" title="/notes/person/19" href="/notes/person/19" active-action="action-notesperson19"><div class="name"> Hedlund</div></a></li><li><a class="flat-box" title="/notes/person/20" href="/notes/person/20" active-action="action-notesperson20"><div class="name"> Gibbs</div></a></li><li><a class="flat-box" title="/notes/person/21" href="/notes/person/21" active-action="action-notesperson21"><div class="name"> Veblen</div></a></li><li><a class="flat-box" title="/notes/person/22" href="/notes/person/22" active-action="action-notesperson22"><div class="name"> Spanier</div></a></li><li><a class="flat-box" title="/notes/person/23" href="/notes/person/23" active-action="action-notesperson23"><div class="name"> Hochschild</div></a></li><li><a class="flat-box" title="/notes/person/24" href="/notes/person/24" active-action="action-notesperson24"><div class="name"> Erdős</div></a></li><li><a class="flat-box" title="/notes/person/25" href="/notes/person/25" active-action="action-notesperson25"><div class="name"> Pólya</div></a></li><li><a class="flat-box" title="/notes/person/26" href="/notes/person/26" active-action="action-notesperson26"><div class="name"> Atiyah</div></a></li><li><a class="flat-box" title="/notes/person/27" href="/notes/person/27" active-action="action-notesperson27"><div class="name"> Singer</div></a></li><li><a class="flat-box" title="/notes/person/28" href="/notes/person/28" active-action="action-notesperson28"><div class="name"> Grothendieck</div></a></li><li><a class="flat-box" title="/notes/person/29" href="/notes/person/29" active-action="action-notesperson29"><div class="name"> Loo-Keng Hua</div></a></li><li><a class="flat-box" title="/notes/person/30" href="/notes/person/30" active-action="action-notesperson30"><div class="name"> Poisson</div></a></li><li><a class="flat-box" title="/notes/person/31" href="/notes/person/31" active-action="action-notesperson31"><div class="name"> Dyson</div></a></li></ul></div></section><div class="widget-sticky pjax"></div><div class="pjax"></div><div class="pjax"></div><div class="pjax"></div><div class="pjax"></div><div class="pjax"></div><div class="pjax"></div><div class="pjax"></div><div class="pjax"></div><div class="pjax"></div><div class="pjax"></div><div class="pjax"></div><div class="pjax"></div><div class="pjax"></div><div class="pjax"></div><div class="pjax"></div><div class="pjax"></div><div class="pjax"></div><div class="pjax"></div><div class="pjax"></div><div class="pjax"></div><div class="pjax"></div><div class="pjax"></div><div class="pjax"></div><div class="pjax"></div><div class="pjax"></div><div class="pjax"></div><div class="pjax"></div><div class="pjax"></div><div class="pjax"></div><div class="pjax"></div><div class="pjax"></div><div class="pjax"></div><div class="pjax"></div><div class="pjax"></div></aside><pjax><script>window.pdata={},pdata.ispage=!1,pdata.commentPath="",pdata.commentPlaceholder="",pdata.commentConfig={};var l_header=document.getElementById("l_header");l_header.classList.add("show");var cover_wrapper=document.querySelector("#l_cover .cover-wrapper"),scroll_down=document.getElementById("scroll-down");cover_wrapper.id="none",cover_wrapper.style.display="none",scroll_down.style.display="none"</script></pjax></div><footer class="footer clearfix" itemscope="" itemtype="http://schema.org/WPFooter"><br><br><div class="aplayer-container"><div class="aplayer-local"></div></div><br><div class="social-wrapper" itemprop="about" itemscope="" itemtype="http://schema.org/Thing"><a href="/atom.xml" class="social fa-duotone fa-rss flat-btn" target="_blank" rel="external nofollow noopener noreferrer" itemprop="url"></a><a href="https://mhuig.top/contact/" class="social fa-duotone fa-envelope flat-btn" target="_blank" rel="external nofollow noopener noreferrer" itemprop="url"></a><a href="https://github.com/MHuiG" class="social fa-brands fa-github flat-btn" target="_blank" rel="external nofollow noopener noreferrer" itemprop="url"></a><a href="https://t.me/MHuiG" class="social fa-brands fa-telegram flat-btn" target="_blank" rel="external nofollow noopener noreferrer" itemprop="url"></a></div><div><p>博客内容遵循 <a target="_blank" rel="external nofollow noopener noreferrer" href="https://creativecommons.org/licenses/by-nc-sa/4.0/deed.zh-hans">署名-非商业性使用-相同方式共享 4.0 国际 (CC BY-NC-SA 4.0) 协议</a></p></div><div class="copyright"><p><a href="https://icp.gov.moe" target="_blank" rel="external nofollow noopener noreferrer">萌ICP备</a> <a href="https://icp.gov.moe/?keyword=2020012138" target="_blank" rel="external nofollow noopener noreferrer">2020012138号</a><br><a target="_blank" rel="noopener" href="https://mhuig.top/">Copyright © Since 2018 MHuiG</a></p></div></footer><a id="s-top" class="fa-solid fa-arrow-up fa-fw" title="top"></a></div></div><div><script>volantis.dom.bodyAnchor=volantis.dom.$(document.getElementById("safearea")),volantis.dom.topBtn=volantis.dom.$(document.getElementById("s-top")),volantis.dom.wrapper=volantis.dom.$(document.getElementById("wrapper")),volantis.dom.coverAnchor=volantis.dom.$(document.querySelector("#l_cover .cover-wrapper")),volantis.dom.switcher=volantis.dom.$(document.querySelector("#l_header .switcher .s-search")),volantis.dom.header=volantis.dom.$(document.getElementById("l_header")),volantis.dom.search=volantis.dom.$(document.querySelector("#l_header .m_search")),volantis.dom.mPhoneList=volantis.dom.$(document.querySelectorAll("#l_header .m-phone .list-v"))</script><script>volantis.css("https://static.mhuig.top/npm/volantis-static@0.0.1660614606622/libs/@fortawesome/fontawesome-pro/css/all.min.css")</script><script src="/js/app.js"></script><script>const rootElement=document.documentElement,darkModeStorageKey="color-scheme",rootElementDarkModeAttributeName="color-scheme",setLS=(e,t)=>{localStorage.setItem(e,t)},removeLS=e=>{localStorage.removeItem(e)},getLS=e=>localStorage.getItem(e),getModeFromCSSMediaQuery=()=>window.matchMedia("(prefers-color-scheme: dark)").matches?"dark":"light",resetRootDarkModeAttributeAndLS=()=>{rootElement.removeAttribute("color-scheme"),removeLS("color-scheme")},validColorModeKeys={dark:!0,light:!0},applyCustomDarkModeSettings=e=>{const t=e||getLS("color-scheme");getCustomDarkMode(),t===getModeFromCSSMediaQuery()?resetRootDarkModeAttributeAndLS():validColorModeKeys[t]?rootElement.setAttribute("color-scheme",t):resetRootDarkModeAttributeAndLS()},invertDarkModeObj={dark:"light",light:"dark"},getCustomDarkMode=()=>{let e=getLS("color-scheme");if(validColorModeKeys[e])e=invertDarkModeObj[e];else{if(null!==e)return;e=invertDarkModeObj[getModeFromCSSMediaQuery()]}volantis.dark.mode="dark"==e?"light":"dark"},toggleCustomDarkMode=()=>{let e=getLS("color-scheme");if(validColorModeKeys[e])e=invertDarkModeObj[e];else{if(null!==e)return;e=invertDarkModeObj[getModeFromCSSMediaQuery()]}return setLS("color-scheme",e),e};function bindToggleButton(){document.querySelectorAll("#wrapper .toggle-mode-btn,#rightmenu-wrapper .toggle-mode-btn").forEach((function(e){volantis.dom.$(e).on("click",volantis.dark.toggle)}))}volantis.dark.toggle=()=>{const e=toggleCustomDarkMode();applyCustomDarkModeSettings(e),volantis.dark.method.toggle.start()},applyCustomDarkModeSettings(),document.addEventListener("DOMContentLoaded",(()=>{volantis.requestAnimationFrame(bindToggleButton)})),volantis.pjax.push(bindToggleButton);const darkModelListeners={dark:e=>{e.matches&&(volantis.dark.mode="dark"),volantis.dark.method.toggle.start()},light:e=>{e.matches&&(volantis.dark.mode="light"),volantis.dark.method.toggle.start()}};window.matchMedia("(prefers-color-scheme: dark)").addListener(darkModelListeners.dark),window.matchMedia("(prefers-color-scheme: light)").addListener(darkModelListeners.light)</script><script>function loadIssuesJS(){null!=document.getElementById("sites-api")&&"undefined"==typeof SitesJS&&volantis.js("/js/plugins/tags/sites.js");null!=document.getElementById("friends-api")&&"undefined"==typeof FriendsJS&&volantis.js("/js/plugins/tags/friends.js");null!=document.getElementById("contributors-api")&&"undefined"==typeof ContributorsJS&&volantis.js("/js/plugins/tags/contributors.js")}loadIssuesJS(),volantis.pjax.push((()=>{loadIssuesJS()}))</script><script defer="" src="https://cdn.bootcdn.net/ajax/libs/vanilla-lazyload/17.1.0/lazyload.min.js"></script><script>window.lazyLoadOptions={elements_selector:".lazyload",threshold:0},window.addEventListener("LazyLoad::Initialized",(function(n){window.lazyLoadInstance=n.detail.instance}),!1),document.addEventListener("DOMContentLoaded",(function(){lazyLoadInstance.update()})),document.addEventListener("pjax:complete",(function(){lazyLoadInstance.update()}))</script><script>window.FPConfig={delay:0,ignoreKeywords:["#"],maxRPS:6,hoverDelay:0}</script><script defer="" src="https://static.mhuig.top/npm/volantis-static@0.0.1660614606622/libs/flying-pages/flying-pages.min.js"></script><script>volantis.css("https://cdn.bootcdn.net/ajax/libs/aplayer/1.10.1/APlayer.min.css"),volantis.js("https://cdn.bootcdn.net/ajax/libs/aplayer/1.10.1/APlayer.min.js").then((()=>{function e(){document.querySelector(".aplayer-local-min")&&document.querySelectorAll(".aplayer-local-min").forEach((e=>{new APlayer(Object.assign({container:e,mini:!0,order:"list",volume:"0.7",autoplay:!1,loop:"all",theme:"#1BCDFC",listMaxHeight:"320px",listFolded:"true",preload:"auto",lrcType:3,audio:[{name:"虹之间",artist:"钢琴版伴奏",url:"https://blog.mhuig.top/music-Archive/BetweenTheRainbow.mp3",lrc:"https://blog.mhuig.top/music-Archive/BetweenTheRainbow.lrc",cover:"https://blog.mhuig.top/music-Archive/BetweenTheRainbow.jpg"},{name:"Avem",artist:"Alan Walker",url:"https://blog.mhuig.top/music-Archive/Avem.mp3",lrc:"https://blog.mhuig.top/music-Archive/Avem.lrc",cover:"https://blog.mhuig.top/music-Archive/Avem.jpg"},{name:"Fly",artist:"Marshmello / Leau Culver",url:"https://blog.mhuig.top/music-Archive/fly.mp3",lrc:"https://blog.mhuig.top/music-Archive/fly.lrc",cover:"https://blog.mhuig.top/music-Archive/fly.jpg"},{name:"Alone",artist:"Marshmello",url:"https://blog.mhuig.top/music-Archive/alone.mp3",lrc:"https://blog.mhuig.top/music-Archive/alone.lrc",cover:"https://blog.mhuig.top/music-Archive/alone.jpg"}]},JSON.parse(e.querySelector(".aplayer-local-min-conf").innerText)))}))}document.querySelectorAll(".aplayer-local").forEach((e=>{new APlayer({container:e,fixed:!1,order:"list",volume:"0.7",autoplay:!1,loop:"all",theme:"#1BCDFC",listMaxHeight:"320px",listFolded:"true",preload:"auto",lrcType:3,audio:[{name:"虹之间",artist:"钢琴版伴奏",url:"https://blog.mhuig.top/music-Archive/BetweenTheRainbow.mp3",lrc:"https://blog.mhuig.top/music-Archive/BetweenTheRainbow.lrc",cover:"https://blog.mhuig.top/music-Archive/BetweenTheRainbow.jpg"},{name:"Avem",artist:"Alan Walker",url:"https://blog.mhuig.top/music-Archive/Avem.mp3",lrc:"https://blog.mhuig.top/music-Archive/Avem.lrc",cover:"https://blog.mhuig.top/music-Archive/Avem.jpg"},{name:"Fly",artist:"Marshmello / Leau Culver",url:"https://blog.mhuig.top/music-Archive/fly.mp3",lrc:"https://blog.mhuig.top/music-Archive/fly.lrc",cover:"https://blog.mhuig.top/music-Archive/fly.jpg"},{name:"Alone",artist:"Marshmello",url:"https://blog.mhuig.top/music-Archive/alone.mp3",lrc:"https://blog.mhuig.top/music-Archive/alone.lrc",cover:"https://blog.mhuig.top/music-Archive/alone.jpg"}]})})),e(),volantis.pjax.push(e,"aplayerMin")}))</script><script>function check_giscus(){return"dark"===volantis.dark.mode?volantis.giscus.Theme="dark":volantis.giscus.Theme="light",document.getElementById("giscus_container")}function pjax_giscus(){const t=check_giscus();if(!t)return;let s=Object.assign({theme:{light:"light",dark:"dark"},repo:"MHuiG/talk","repo-id":"MDEwOlJlcG9zaXRvcnkyODQ4NDg1NTg=",category:"Giscus","category-id":"DIC_kwDOEPpxrs4B_X67",mapping:"pathname","reactions-enabled":"1","emit-metadata":"1",lang:"zh-CN","input-position":"top"},pdata.commentConfig);const e=document.createElement("script");e.setAttribute("src","https://giscus.app/client.js"),Object.keys(s).forEach((t=>{"theme"!=t&&e.setAttribute("data-"+t,s[t])})),e.setAttribute("data-theme",volantis.giscus.Theme),e.setAttribute("crossorigin","anonymous"),t.appendChild(e)}function dark_giscus(){if(!check_giscus())return;const t={setConfig:{theme:volantis.giscus.Theme}};document.querySelector("iframe.giscus-frame").contentWindow.postMessage({giscus:t},"https://giscus.app")}volantis.layoutHelper("comments",'<div id="giscus_container"></div>'),volantis.giscus={},pjax_giscus(),volantis.pjax.push(pjax_giscus),volantis.dark.push(dark_giscus)</script><script>async function loadSearchScript(){return volantis.js("/js/search/hexo.js")}function loadSearchService(){loadSearchScript(),document.querySelectorAll(".input.u-search-input").forEach((e=>{e.removeEventListener("focus",loadSearchService,!1)})),document.querySelectorAll(".u-search-form").forEach((e=>{e.addEventListener("submit",(e=>{e.preventDefault()}),!1)}))}function OpenSearch(e){"undefined"==typeof SearchService?loadSearchScript().then((()=>{SearchService.setQueryText(e),SearchService.search()})):(SearchService.setQueryText(e),SearchService.search())}if(window.location.search&&/^\?s=/g.test(window.location.search)){OpenSearch(decodeURI(window.location.search).replace(/\ /g,"-").replace(/^\?s=/g,""))}document.querySelectorAll(".input.u-search-input").forEach((e=>{e.addEventListener("focus",loadSearchService,!1)}))</script><script>function pjax_highlightjs_copyCode(){(document.querySelector(".highlight .code pre")||document.querySelector(".article pre code"))&&VolantisApp.utilCopyCode(".highlight .code pre, .article pre code")}volantis.requestAnimationFrame(pjax_highlightjs_copyCode),volantis.pjax.push(pjax_highlightjs_copyCode)</script><script>function load_swiper(){document.querySelectorAll(".swiper-container")[0]&&(volantis.css("https://cdn.bootcdn.net/ajax/libs/Swiper/8.3.2/swiper-bundle.min.css"),volantis.js("https://cdn.bootcdn.net/ajax/libs/Swiper/8.3.2/swiper-bundle.min.js").then((()=>{pjax_swiper()})))}function pjax_swiper(){volantis.swiper=new Swiper(".swiper-container",{slidesPerView:"auto",spaceBetween:8,centeredSlides:!0,loop:!0,pagination:{el:".swiper-pagination",clickable:!0},navigation:{nextEl:".swiper-button-next",prevEl:".swiper-button-prev"}})}load_swiper(),volantis.pjax.push((()=>{document.querySelectorAll(".swiper-container")[0]&&(void 0===volantis.swiper?load_swiper():pjax_swiper())}))</script><script>volantis.css("https://cdn.bootcdn.net/ajax/libs/pace/1.2.4/themes/blue/pace-theme-minimal.min.css"),volantis.js("https://cdn.bootcdn.net/ajax/libs/pace/1.2.4/pace.min.js").then((()=>{Pace.options.restartOnPushState=!1,volantis.pjax.send(Pace.restart,"Pace.restart"),volantis.scroll.push(volantis.debounce((()=>{Pace.stop(),Pace.trigger("start"),Pace.bar.update(100*volantis.scroll.progress()),document.body.className=document.body.className.replaceAll("pace-running ","")})),"阅读进度")}))</script><pjax></pjax><script>function listenSidebarTOC(){const t=document.querySelectorAll(".toc li");if(!t.length)return;const e=[];Array.from(t).forEach((t=>{const n=t.querySelector(".toc-link"),i=document.getElementById(n.getAttribute("href")?decodeURI(n.getAttribute("href")).replace("#",""):n.getAttribute("toc-action").split("toc-")[1]);return e.push(i),n.getAttribute("href")&&(n.setAttribute("toc-action","toc-"+decodeURI(n.getAttribute("href")).replace("#","")),n.removeAttribute("href")),i&&i.id&&n.addEventListener("click",(t=>{t.preventDefault(),volantis.scroll.to(i,{addTop:5,observer:!0}),history.pushState(null,document.title,"#"+i.id)})),i}));function n(t){if(t.classList.contains("active-current"))return;document.querySelectorAll(".toc .active").forEach((t=>{t.classList.remove("active","active-current")})),t.classList.add("active","active-current");let e=t.parentNode;for(;!e.matches(".toc");)e.matches("li")&&e.classList.add("active"),e=e.parentNode}volantis.activateNavIndex=0,n(t[volantis.activateNavIndex]),e[0]&&volantis.scroll.push(volantis.debounce((()=>{if(e[0].getBoundingClientRect().top>=0)volantis.activateNavIndex=0;else if(e[e.length-1].getBoundingClientRect().top<0)volantis.activateNavIndex=e.length-1;else for(let t=0;t<e.length;t++){const n=e[t],i=e[(t+1)%e.length];if(n.getBoundingClientRect().top<0&&i.getBoundingClientRect().top>=0){volantis.activateNavIndex=t;break}}n(t[volantis.activateNavIndex])})),"sidebar-toc")}document.addEventListener("DOMContentLoaded",(()=>{volantis.requestAnimationFrame(listenSidebarTOC)})),volantis.pjax.push(listenSidebarTOC,"listenSidebarTOC")</script><script>try{let e=(e,t,n=2)=>Math.abs(e-t)<=n,t=(t,n)=>!e(t.width,n.width)||!e(t.height,n.height),n=new WeakMap,i=(e,i=e.getClientBoundingRect())=>{let o=n.get(e);o&&!t(o,i)||(n.set(e,i),e.style["contain-intrinsic-size"]=`${i.width}px ${i.height}px`)},o=new IntersectionObserver(((e,t)=>{e.forEach((e=>{i(e.target,e.boundingClientRect)}))}),{rootMargin:"500px 0px 500px 0px"}),r=new ResizeObserver(((e,t)=>{e.forEach((e=>{i(e.target,e.contentRect)}))})),s=e=>{let t=document.querySelectorAll(e);t.length&&(t.forEach((e=>{o.observe(e),r.observe(e)})),requestAnimationFrame((()=>{requestAnimationFrame((()=>{t[0].style["content-visibility"]="auto"}))})))},a=()=>{"content-visibility"in document.documentElement.style&&s(".post-story")};a(),volantis.pjax.push(a)}catch(e){console.log(e)}</script><script>document.onreadystatechange=function(){if("complete"==document.readyState){const{saveData:e,effectiveType:t}=navigator.connection||navigator.mozConnection||navigator.webkitConnection||{};("none"==getComputedStyle(document.querySelector("#safearea"),null).display||e||/2g/.test(t))&&(document.querySelectorAll(".reveal").forEach((function(e){e.style.opacity="1"})),document.querySelector("#safearea").style.display="block")}}</script><script src="https://cdn.bootcdn.net/ajax/libs/pjax/0.2.8/pjax.min.js"></script><script>const performanceMonitor={slowThreshold:800,slowCount:0,maxSlowAllowed:1,requestStartTime:0,start(){this.requestStartTime=Date.now()},check(){Date.now()-this.requestStartTime>this.slowThreshold?this.slowCount++:this.slowCount=0},res(){return this.slowCount>=this.maxSlowAllowed}};var pjax;document.addEventListener("DOMContentLoaded",(function(){pjax=new Pjax({elements:'a[href]:not([href^="#"]):not([href="javascript:void(0)"]):not([pjax-fancybox]):not([onclick="return false;"]):not([onclick="return!1"]):not([target="_blank"]):not([target="view_window"]):not([href$=".xml"])',selectors:["head title","head meta[name=keywords]","head meta[name=description]","#l_main","#pjax-header-nav-list",".pjax","pjax","meta[name=robots]","link[rel=canonical]","meta[property='og:title']","meta[property='og:description']","meta[property='og:url']","meta[property='og:image']","script[type='application/ld+json']"],cacheBust:!1,timeout:900})})),document.addEventListener("pjax:send",(function(e){window.stop(),performanceMonitor.start();try{var t=window.location.pathname,o=e.triggerElement.href,n=[""];""!=n[0]&&n.forEach((e=>{-1==t.indexOf(e)&&-1==o.indexOf(e)||(window.location.href=o)})),performanceMonitor.res()&&(window.location.href=o)}catch(e){}volantis.pjax.method.send.start()})),document.addEventListener("pjax:complete",(function(){performanceMonitor.check(),document.querySelectorAll("script[data-pjax], .pjax-reload script").forEach((e=>{const t=e.text||e.textContent||e.innerHTML||"",o=document.createElement("script");Object.keys(e.attributes).forEach((t=>{o.setAttribute(e.attributes[t].nodeName,e.attributes[t].nodeValue)})),t&&o.appendChild(document.createTextNode(t)),e.parentNode.replaceChild(o,e)})),volantis.pjax.method.complete.start()})),document.addEventListener("pjax:error",(function(e){"pjax"===volantis.debug?(console.error(e),console.log("pjax error: \n"+JSON.stringify(e))):(volantis.pjax.method.error.start(),window.location.href=e.triggerElement.href)}))</script></div><pjax> <a style="display:none" target="_blank" rel="external nofollow noopener noreferrer" href="https://bot-trap.mhuig.top/">Are You A Robot?</a></pjax><script>(()=>{function t(){if("localhost:4000"!=window.location.host&&!/blog\.mhuig\.top/.test(window.location.host)){const t=document.createElement("meta");t.name="robots",t.content=atob("bm9pbmRleCwgbm9mb2xsb3csIG5vYXJjaGl2ZQ=="),document.head.appendChild(t)}}function o(){document.querySelector("figcaption")&&document.querySelectorAll("figcaption").forEach((t=>{volantis.dom.$(t).on("click",(function(){const t=!window.CodeBlockFullscreen;window.CodeBlockFullscreen=t;const o=document.getElementById("post")||document.getElementById("docs")||document.getElementById("page");if(!o)return;const e=this.parentElement,n=e.parentElement,l=document.documentElement,c=document.querySelectorAll(".highlight > table .gutter");o.classList.toggle("code-block-fullscreen",t),e.classList.toggle("code-block-fullscreen",t),n.classList.toggle("code-block-fullscreen",t),e.classList.toggle("code-block-fullscreen-overflow-auto",t),l.classList.toggle("code-block-fullscreen-html-scroll",t),c.forEach((o=>{o.classList.toggle("code-block-fullscreen-gutter",t)}))}))}))}t(),volantis.pjax.push(t),top.location!=self.location&&(top.location=self.location),"mhuig.github.io"==window.location.host||"localhost:4000"==window.location.host||/mhuig\.top$/.test(window.location.host)||/kix\.moe$/.test(window.location.host)||/mhuig/.test(window.location.host)||/ipfs/.test(window.location.host)||(window.location.href=atob("aHR0cHM6Ly9ibG9nLm1odWlnLnRvcC8=")),o(),volantis.pjax.push(o);const e=[{month:12,day:13},function(){const t=(new Date).getFullYear(),o=t%100,e=t>=2e3?4.81:5.59,n=Math.floor(o/4),l=Math.floor(.2422*o+e)-n;return{month:4,day:Math.max(4,l)}}(),{month:7,day:7},{month:9,day:18},{month:9,day:30}];function n(){document.documentElement.classList.remove("mourning-mode");if(!["/","/index.html","/index.htm","/index"].includes(window.location.pathname))return;const t=new Date,o=t.getMonth()+1,n=t.getDate();e.some((t=>t.month===o&&t.day===n))&&document.documentElement.classList.add("mourning-mode")}const l=document.createElement("style");l.textContent="\n      html.mourning-mode {\n        filter: grayscale(100%);\n        -webkit-filter: grayscale(100%);\n        transition: filter 0.5s ease;\n      }\n    ",document.head.appendChild(l),n(),document.addEventListener("pjax:complete",n)})()</script></body></html>