CINXE.COM

<!DOCTYPE html> <html class="client-nojs vector-feature-language-in-header-enabled vector-feature-language-in-main-page-header-disabled vector-feature-sticky-header-disabled vector-feature-page-tools-pinned-disabled vector-feature-toc-pinned-clientpref-1 vector-feature-main-menu-pinned-disabled vector-feature-limited-width-clientpref-1 vector-feature-limited-width-content-enabled vector-feature-custom-font-size-clientpref-1 vector-feature-appearance-pinned-clientpref-1 vector-feature-night-mode-enabled skin-theme-clientpref-day vector-toc-available" lang="en" dir="ltr"> <head> <meta charset="UTF-8"> <title>QCD matter - Wikipedia</title> <script>(function(){var className="client-js vector-feature-language-in-header-enabled vector-feature-language-in-main-page-header-disabled vector-feature-sticky-header-disabled vector-feature-page-tools-pinned-disabled vector-feature-toc-pinned-clientpref-1 vector-feature-main-menu-pinned-disabled vector-feature-limited-width-clientpref-1 vector-feature-limited-width-content-enabled vector-feature-custom-font-size-clientpref-1 vector-feature-appearance-pinned-clientpref-1 vector-feature-night-mode-enabled skin-theme-clientpref-day vector-toc-available";var cookie=document.cookie.match(/(?:^|; )enwikimwclientpreferences=([^;]+)/);if(cookie){cookie[1].split('%2C').forEach(function(pref){className=className.replace(new RegExp('(^| )'+pref.replace(/-clientpref-\w+$|[^\w-]+/g,'')+'-clientpref-\\w+( |$)'),'$1'+pref+'$2');});}document.documentElement.className=className;}());RLCONF={"wgBreakFrames":false,"wgSeparatorTransformTable":["",""],"wgDigitTransformTable":["",""],"wgDefaultDateFormat":"dmy", "wgMonthNames":["","January","February","March","April","May","June","July","August","September","October","November","December"],"wgRequestId":"266c7641-6825-44a5-95f5-af1f448eb374","wgCanonicalNamespace":"","wgCanonicalSpecialPageName":false,"wgNamespaceNumber":0,"wgPageName":"QCD_matter","wgTitle":"QCD matter","wgCurRevisionId":1216611248,"wgRevisionId":1216611248,"wgArticleId":1919367,"wgIsArticle":true,"wgIsRedirect":false,"wgAction":"view","wgUserName":null,"wgUserGroups":["*"],"wgCategories":["CS1: long volume value","Articles with short description","Short description is different from Wikidata","Pages displaying short descriptions of redirect targets via Module:Annotated link","Quark matter","Quantum chromodynamics","Phases of matter","Unsolved problems in physics"],"wgPageViewLanguage":"en","wgPageContentLanguage":"en","wgPageContentModel":"wikitext","wgRelevantPageName":"QCD_matter","wgRelevantArticleId":1919367,"wgIsProbablyEditable":true,"wgRelevantPageIsProbablyEditable": true,"wgRestrictionEdit":[],"wgRestrictionMove":[],"wgRedirectedFrom":"Quark_matter","wgNoticeProject":"wikipedia","wgCiteReferencePreviewsActive":false,"wgFlaggedRevsParams":{"tags":{"status":{"levels":1}}},"wgMediaViewerOnClick":true,"wgMediaViewerEnabledByDefault":true,"wgPopupsFlags":0,"wgVisualEditor":{"pageLanguageCode":"en","pageLanguageDir":"ltr","pageVariantFallbacks":"en"},"wgMFDisplayWikibaseDescriptions":{"search":true,"watchlist":true,"tagline":false,"nearby":true},"wgWMESchemaEditAttemptStepOversample":false,"wgWMEPageLength":20000,"wgInternalRedirectTargetUrl":"/wiki/QCD_matter","wgRelatedArticlesCompat":[],"wgCentralAuthMobileDomain":false,"wgEditSubmitButtonLabelPublish":true,"wgULSPosition":"interlanguage","wgULSisCompactLinksEnabled":false,"wgVector2022LanguageInHeader":true,"wgULSisLanguageSelectorEmpty":false,"wgWikibaseItemId":"Q2755153","wgCheckUserClientHintsHeadersJsApi":["brands","architecture","bitness","fullVersionList","mobile","model","platform", "platformVersion"],"GEHomepageSuggestedEditsEnableTopics":true,"wgGETopicsMatchModeEnabled":false,"wgGEStructuredTaskRejectionReasonTextInputEnabled":false,"wgGELevelingUpEnabledForUser":false};RLSTATE={"ext.globalCssJs.user.styles":"ready","site.styles":"ready","user.styles":"ready","ext.globalCssJs.user":"ready","user":"ready","user.options":"loading","ext.cite.styles":"ready","skins.vector.search.codex.styles":"ready","skins.vector.styles":"ready","skins.vector.icons":"ready","jquery.makeCollapsible.styles":"ready","ext.wikimediamessages.styles":"ready","ext.visualEditor.desktopArticleTarget.noscript":"ready","ext.uls.interlanguage":"ready","wikibase.client.init":"ready","ext.wikimediaBadges":"ready"};RLPAGEMODULES=["mediawiki.action.view.redirect","ext.cite.ux-enhancements","mediawiki.page.media","site","mediawiki.page.ready","jquery.makeCollapsible","mediawiki.toc","skins.vector.js","ext.centralNotice.geoIP","ext.centralNotice.startUp","ext.gadget.ReferenceTooltips", "ext.gadget.switcher","ext.urlShortener.toolbar","ext.centralauth.centralautologin","mmv.bootstrap","ext.popups","ext.visualEditor.desktopArticleTarget.init","ext.visualEditor.targetLoader","ext.echo.centralauth","ext.eventLogging","ext.wikimediaEvents","ext.navigationTiming","ext.uls.interface","ext.cx.eventlogging.campaigns","ext.cx.uls.quick.actions","wikibase.client.vector-2022","ext.checkUser.clientHints","ext.quicksurveys.init","ext.growthExperiments.SuggestedEditSession","wikibase.sidebar.tracking"];</script> <script>(RLQ=window.RLQ||[]).push(function(){mw.loader.impl(function(){return["user.options@12s5i",function($,jQuery,require,module){mw.user.tokens.set({"patrolToken":"+\\","watchToken":"+\\","csrfToken":"+\\"}); }];});});</script> <link rel="stylesheet" href="/w/load.php?lang=en&modules=ext.cite.styles%7Cext.uls.interlanguage%7Cext.visualEditor.desktopArticleTarget.noscript%7Cext.wikimediaBadges%7Cext.wikimediamessages.styles%7Cjquery.makeCollapsible.styles%7Cskins.vector.icons%2Cstyles%7Cskins.vector.search.codex.styles%7Cwikibase.client.init&only=styles&skin=vector-2022"> <script async="" src="/w/load.php?lang=en&modules=startup&only=scripts&raw=1&skin=vector-2022"></script> <meta name="ResourceLoaderDynamicStyles" content=""> <link rel="stylesheet" href="/w/load.php?lang=en&modules=site.styles&only=styles&skin=vector-2022"> <meta name="generator" content="MediaWiki 1.44.0-wmf.4"> <meta name="referrer" content="origin"> <meta name="referrer" content="origin-when-cross-origin"> <meta name="robots" content="max-image-preview:standard"> <meta name="format-detection" content="telephone=no"> <meta name="viewport" content="width=1120"> <meta property="og:title" content="QCD matter - Wikipedia"> <meta property="og:type" content="website"> <link rel="preconnect" href="//upload.wikimedia.org"> <link rel="alternate" media="only screen and (max-width: 640px)" href="//en.m.wikipedia.org/wiki/QCD_matter"> <link rel="alternate" type="application/x-wiki" title="Edit this page" href="/w/index.php?title=QCD_matter&action=edit"> <link rel="apple-touch-icon" href="/static/apple-touch/wikipedia.png"> <link rel="icon" href="/static/favicon/wikipedia.ico"> <link rel="search" type="application/opensearchdescription+xml" href="/w/rest.php/v1/search" title="Wikipedia (en)"> <link rel="EditURI" type="application/rsd+xml" href="//en.wikipedia.org/w/api.php?action=rsd"> <link rel="canonical" href="https://en.wikipedia.org/wiki/QCD_matter"> <link rel="license" href="https://creativecommons.org/licenses/by-sa/4.0/deed.en"> <link rel="alternate" type="application/atom+xml" title="Wikipedia Atom feed" href="/w/index.php?title=Special:RecentChanges&feed=atom"> <link rel="dns-prefetch" href="//meta.wikimedia.org" /> <link rel="dns-prefetch" href="//login.wikimedia.org"> </head> <body class="skin--responsive skin-vector skin-vector-search-vue mediawiki ltr sitedir-ltr mw-hide-empty-elt ns-0 ns-subject mw-editable page-QCD_matter rootpage-QCD_matter skin-vector-2022 action-view"><a class="mw-jump-link" href="#bodyContent">Jump to content</a> <div class="vector-header-container"> <header class="vector-header mw-header"> <div class="vector-header-start"> <nav class="vector-main-menu-landmark" aria-label="Site"> <div id="vector-main-menu-dropdown" class="vector-dropdown vector-main-menu-dropdown vector-button-flush-left vector-button-flush-right" > <input type="checkbox" id="vector-main-menu-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-main-menu-dropdown" class="vector-dropdown-checkbox " aria-label="Main menu" > <label id="vector-main-menu-dropdown-label" for="vector-main-menu-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-menu mw-ui-icon-wikimedia-menu"></span> <span class="vector-dropdown-label-text">Main menu</span> </label> <div class="vector-dropdown-content"> <div id="vector-main-menu-unpinned-container" class="vector-unpinned-container"> <div id="vector-main-menu" class="vector-main-menu vector-pinnable-element"> <div class="vector-pinnable-header vector-main-menu-pinnable-header vector-pinnable-header-unpinned" data-feature-name="main-menu-pinned" data-pinnable-element-id="vector-main-menu" data-pinned-container-id="vector-main-menu-pinned-container" data-unpinned-container-id="vector-main-menu-unpinned-container" > <div class="vector-pinnable-header-label">Main menu</div> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-main-menu.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-main-menu.unpin">hide</button> </div> <div id="p-navigation" class="vector-menu mw-portlet mw-portlet-navigation" > <div class="vector-menu-heading"> Navigation </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="n-mainpage-description" class="mw-list-item"><a href="/wiki/Main_Page" title="Visit the main page [z]" accesskey="z"><span>Main page</span></a></li><li id="n-contents" class="mw-list-item"><a href="/wiki/Wikipedia:Contents" title="Guides to browsing Wikipedia"><span>Contents</span></a></li><li id="n-currentevents" class="mw-list-item"><a href="/wiki/Portal:Current_events" title="Articles related to current events"><span>Current events</span></a></li><li id="n-randompage" class="mw-list-item"><a href="/wiki/Special:Random" title="Visit a randomly selected article [x]" accesskey="x"><span>Random article</span></a></li><li id="n-aboutsite" class="mw-list-item"><a href="/wiki/Wikipedia:About" title="Learn about Wikipedia and how it works"><span>About Wikipedia</span></a></li><li id="n-contactpage" class="mw-list-item"><a href="//en.wikipedia.org/wiki/Wikipedia:Contact_us" title="How to contact Wikipedia"><span>Contact us</span></a></li> </ul> </div> </div> <div id="p-interaction" class="vector-menu mw-portlet mw-portlet-interaction" > <div class="vector-menu-heading"> Contribute </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="n-help" class="mw-list-item"><a href="/wiki/Help:Contents" title="Guidance on how to use and edit Wikipedia"><span>Help</span></a></li><li id="n-introduction" class="mw-list-item"><a href="/wiki/Help:Introduction" title="Learn how to edit Wikipedia"><span>Learn to edit</span></a></li><li id="n-portal" class="mw-list-item"><a href="/wiki/Wikipedia:Community_portal" title="The hub for editors"><span>Community portal</span></a></li><li id="n-recentchanges" class="mw-list-item"><a href="/wiki/Special:RecentChanges" title="A list of recent changes to Wikipedia [r]" accesskey="r"><span>Recent changes</span></a></li><li id="n-upload" class="mw-list-item"><a href="/wiki/Wikipedia:File_upload_wizard" title="Add images or other media for use on Wikipedia"><span>Upload file</span></a></li> </ul> </div> </div> </div> </div> </div> </div> </nav> <a href="/wiki/Main_Page" class="mw-logo"> <img class="mw-logo-icon" src="/static/images/icons/wikipedia.png" alt="" aria-hidden="true" height="50" width="50"> <span class="mw-logo-container skin-invert"> <img class="mw-logo-wordmark" alt="Wikipedia" src="/static/images/mobile/copyright/wikipedia-wordmark-en.svg" style="width: 7.5em; height: 1.125em;"> <img class="mw-logo-tagline" alt="The Free Encyclopedia" src="/static/images/mobile/copyright/wikipedia-tagline-en.svg" width="117" height="13" style="width: 7.3125em; height: 0.8125em;"> </span> </a> </div> <div class="vector-header-end"> <div id="p-search" role="search" class="vector-search-box-vue vector-search-box-collapses vector-search-box-show-thumbnail vector-search-box-auto-expand-width vector-search-box"> <a href="/wiki/Special:Search" class="cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only search-toggle" title="Search Wikipedia [f]" accesskey="f"><span class="vector-icon mw-ui-icon-search mw-ui-icon-wikimedia-search"></span> <span>Search</span> </a> <div class="vector-typeahead-search-container"> <div class="cdx-typeahead-search cdx-typeahead-search--show-thumbnail cdx-typeahead-search--auto-expand-width"> <form action="/w/index.php" id="searchform" class="cdx-search-input cdx-search-input--has-end-button"> <div id="simpleSearch" class="cdx-search-input__input-wrapper" data-search-loc="header-moved"> <div class="cdx-text-input cdx-text-input--has-start-icon"> <input class="cdx-text-input__input" type="search" name="search" placeholder="Search Wikipedia" aria-label="Search Wikipedia" autocapitalize="sentences" title="Search Wikipedia [f]" accesskey="f" id="searchInput" > <span class="cdx-text-input__icon cdx-text-input__start-icon"></span> </div> <input type="hidden" name="title" value="Special:Search"> </div> <button class="cdx-button cdx-search-input__end-button">Search</button> </form> </div> </div> </div> <nav class="vector-user-links vector-user-links-wide" aria-label="Personal tools"> <div class="vector-user-links-main"> <div id="p-vector-user-menu-preferences" class="vector-menu mw-portlet emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> <div id="p-vector-user-menu-userpage" class="vector-menu mw-portlet emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> <nav class="vector-appearance-landmark" aria-label="Appearance"> <div id="vector-appearance-dropdown" class="vector-dropdown " title="Change the appearance of the page's font size, width, and color" > <input type="checkbox" id="vector-appearance-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-appearance-dropdown" class="vector-dropdown-checkbox " aria-label="Appearance" > <label id="vector-appearance-dropdown-label" for="vector-appearance-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-appearance mw-ui-icon-wikimedia-appearance"></span> <span class="vector-dropdown-label-text">Appearance</span> </label> <div class="vector-dropdown-content"> <div id="vector-appearance-unpinned-container" class="vector-unpinned-container"> </div> </div> </div> </nav> <div id="p-vector-user-menu-notifications" class="vector-menu mw-portlet emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> <div id="p-vector-user-menu-overflow" class="vector-menu mw-portlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="pt-sitesupport-2" class="user-links-collapsible-item mw-list-item user-links-collapsible-item"><a data-mw="interface" href="https://donate.wikimedia.org/wiki/Special:FundraiserRedirector?utm_source=donate&utm_medium=sidebar&utm_campaign=C13_en.wikipedia.org&uselang=en" class=""><span>Donate</span></a> </li> <li id="pt-createaccount-2" class="user-links-collapsible-item mw-list-item user-links-collapsible-item"><a data-mw="interface" href="/w/index.php?title=Special:CreateAccount&returnto=QCD+matter" title="You are encouraged to create an account and log in; however, it is not mandatory" class=""><span>Create account</span></a> </li> <li id="pt-login-2" class="user-links-collapsible-item mw-list-item user-links-collapsible-item"><a data-mw="interface" href="/w/index.php?title=Special:UserLogin&returnto=QCD+matter" title="You're encouraged to log in; however, it's not mandatory. [o]" accesskey="o" class=""><span>Log in</span></a> </li> </ul> </div> </div> </div> <div id="vector-user-links-dropdown" class="vector-dropdown vector-user-menu vector-button-flush-right vector-user-menu-logged-out" title="Log in and more options" > <input type="checkbox" id="vector-user-links-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-user-links-dropdown" class="vector-dropdown-checkbox " aria-label="Personal tools" > <label id="vector-user-links-dropdown-label" for="vector-user-links-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-ellipsis mw-ui-icon-wikimedia-ellipsis"></span> <span class="vector-dropdown-label-text">Personal tools</span> </label> <div class="vector-dropdown-content"> <div id="p-personal" class="vector-menu mw-portlet mw-portlet-personal user-links-collapsible-item" title="User menu" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="pt-sitesupport" class="user-links-collapsible-item mw-list-item"><a href="https://donate.wikimedia.org/wiki/Special:FundraiserRedirector?utm_source=donate&utm_medium=sidebar&utm_campaign=C13_en.wikipedia.org&uselang=en"><span>Donate</span></a></li><li id="pt-createaccount" class="user-links-collapsible-item mw-list-item"><a href="/w/index.php?title=Special:CreateAccount&returnto=QCD+matter" title="You are encouraged to create an account and log in; however, it is not mandatory"><span class="vector-icon mw-ui-icon-userAdd mw-ui-icon-wikimedia-userAdd"></span> <span>Create account</span></a></li><li id="pt-login" class="user-links-collapsible-item mw-list-item"><a href="/w/index.php?title=Special:UserLogin&returnto=QCD+matter" title="You're encouraged to log in; however, it's not mandatory. [o]" accesskey="o"><span class="vector-icon mw-ui-icon-logIn mw-ui-icon-wikimedia-logIn"></span> <span>Log in</span></a></li> </ul> </div> </div> <div id="p-user-menu-anon-editor" class="vector-menu mw-portlet mw-portlet-user-menu-anon-editor" > <div class="vector-menu-heading"> Pages for logged out editors <a href="/wiki/Help:Introduction" aria-label="Learn more about editing"><span>learn more</span></a> </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="pt-anoncontribs" class="mw-list-item"><a href="/wiki/Special:MyContributions" title="A list of edits made from this IP address [y]" accesskey="y"><span>Contributions</span></a></li><li id="pt-anontalk" class="mw-list-item"><a href="/wiki/Special:MyTalk" title="Discussion about edits from this IP address [n]" accesskey="n"><span>Talk</span></a></li> </ul> </div> </div> </div> </div> </nav> </div> </header> </div> <div class="mw-page-container"> <div class="mw-page-container-inner"> <div class="vector-sitenotice-container"> <div id="siteNotice"></div> </div> <div class="vector-column-start"> <div class="vector-main-menu-container"> <div id="mw-navigation"> <nav id="mw-panel" class="vector-main-menu-landmark" aria-label="Site"> <div id="vector-main-menu-pinned-container" class="vector-pinned-container"> </div> </nav> </div> </div> <div class="vector-sticky-pinned-container"> <nav id="mw-panel-toc" aria-label="Contents" data-event-name="ui.sidebar-toc" class="mw-table-of-contents-container vector-toc-landmark"> <div id="vector-toc-pinned-container" class="vector-pinned-container"> <div id="vector-toc" class="vector-toc vector-pinnable-element"> <div class="vector-pinnable-header vector-toc-pinnable-header vector-pinnable-header-pinned" data-feature-name="toc-pinned" data-pinnable-element-id="vector-toc" > <h2 class="vector-pinnable-header-label">Contents</h2> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-toc.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-toc.unpin">hide</button> </div> <ul class="vector-toc-contents" id="mw-panel-toc-list"> <li id="toc-mw-content-text" class="vector-toc-list-item vector-toc-level-1"> <a href="#" class="vector-toc-link"> <div class="vector-toc-text">(Top)</div> </a> </li> <li id="toc-Occurrence" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Occurrence"> <div class="vector-toc-text"> <span class="vector-toc-numb">1</span> <span>Occurrence</span> </div> </a> <button aria-controls="toc-Occurrence-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Occurrence subsection</span> </button> <ul id="toc-Occurrence-sublist" class="vector-toc-list"> <li id="toc-Natural_occurrence" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Natural_occurrence"> <div class="vector-toc-text"> <span class="vector-toc-numb">1.1</span> <span>Natural occurrence</span> </div> </a> <ul id="toc-Natural_occurrence-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Laboratory_experiments" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Laboratory_experiments"> <div class="vector-toc-text"> <span class="vector-toc-numb">1.2</span> <span>Laboratory experiments</span> </div> </a> <ul id="toc-Laboratory_experiments-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> <li id="toc-Thermodynamics" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Thermodynamics"> <div class="vector-toc-text"> <span class="vector-toc-numb">2</span> <span>Thermodynamics</span> </div> </a> <ul id="toc-Thermodynamics-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Phase_diagram" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Phase_diagram"> <div class="vector-toc-text"> <span class="vector-toc-numb">3</span> <span>Phase diagram</span> </div> </a> <ul id="toc-Phase_diagram-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Theoretical_challenges:_calculation_techniques" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Theoretical_challenges:_calculation_techniques"> <div class="vector-toc-text"> <span class="vector-toc-numb">4</span> <span>Theoretical challenges: calculation techniques</span> </div> </a> <button aria-controls="toc-Theoretical_challenges:_calculation_techniques-sublist" class="cdx-button cdx-button--weight-quiet cdx-button--icon-only vector-toc-toggle"> <span class="vector-icon mw-ui-icon-wikimedia-expand"></span> <span>Toggle Theoretical challenges: calculation techniques subsection</span> </button> <ul id="toc-Theoretical_challenges:_calculation_techniques-sublist" class="vector-toc-list"> <li id="toc-Lattice_gauge_theory" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Lattice_gauge_theory"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.1</span> <span>Lattice gauge theory</span> </div> </a> <ul id="toc-Lattice_gauge_theory-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Weak_coupling_theory" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Weak_coupling_theory"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.2</span> <span>Weak coupling theory</span> </div> </a> <ul id="toc-Weak_coupling_theory-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Models" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Models"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.3</span> <span>Models</span> </div> </a> <ul id="toc-Models-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Effective_theories" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Effective_theories"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.4</span> <span>Effective theories</span> </div> </a> <ul id="toc-Effective_theories-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Other_approaches" class="vector-toc-list-item vector-toc-level-2"> <a class="vector-toc-link" href="#Other_approaches"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.5</span> <span>Other approaches</span> </div> </a> <ul id="toc-Other_approaches-sublist" class="vector-toc-list"> <li id="toc-1/N_expansion" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#1/N_expansion"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.5.1</span> <span>1/N expansion</span> </div> </a> <ul id="toc-1/N_expansion-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Supersymmetry" class="vector-toc-list-item vector-toc-level-3"> <a class="vector-toc-link" href="#Supersymmetry"> <div class="vector-toc-text"> <span class="vector-toc-numb">4.5.2</span> <span>Supersymmetry</span> </div> </a> <ul id="toc-Supersymmetry-sublist" class="vector-toc-list"> </ul> </li> </ul> </li> </ul> </li> <li id="toc-Experimental_challenges" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Experimental_challenges"> <div class="vector-toc-text"> <span class="vector-toc-numb">5</span> <span>Experimental challenges</span> </div> </a> <ul id="toc-Experimental_challenges-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Evidence" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Evidence"> <div class="vector-toc-text"> <span class="vector-toc-numb">6</span> <span>Evidence</span> </div> </a> <ul id="toc-Evidence-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-See_also" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#See_also"> <div class="vector-toc-text"> <span class="vector-toc-numb">7</span> <span>See also</span> </div> </a> <ul id="toc-See_also-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Sources_and_further_reading" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Sources_and_further_reading"> <div class="vector-toc-text"> <span class="vector-toc-numb">8</span> <span>Sources and further reading</span> </div> </a> <ul id="toc-Sources_and_further_reading-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-References" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#References"> <div class="vector-toc-text"> <span class="vector-toc-numb">9</span> <span>References</span> </div> </a> <ul id="toc-References-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-External_links" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#External_links"> <div class="vector-toc-text"> <span class="vector-toc-numb">10</span> <span>External links</span> </div> </a> <ul id="toc-External_links-sublist" class="vector-toc-list"> </ul> </li> </ul> </div> </div> </nav> </div> </div> <div class="mw-content-container"> <main id="content" class="mw-body"> <header class="mw-body-header vector-page-titlebar"> <nav aria-label="Contents" class="vector-toc-landmark"> <div id="vector-page-titlebar-toc" class="vector-dropdown vector-page-titlebar-toc vector-button-flush-left" > <input type="checkbox" id="vector-page-titlebar-toc-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-page-titlebar-toc" class="vector-dropdown-checkbox " aria-label="Toggle the table of contents" > <label id="vector-page-titlebar-toc-label" for="vector-page-titlebar-toc-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-listBullet mw-ui-icon-wikimedia-listBullet"></span> <span class="vector-dropdown-label-text">Toggle the table of contents</span> </label> <div class="vector-dropdown-content"> <div id="vector-page-titlebar-toc-unpinned-container" class="vector-unpinned-container"> </div> </div> </div> </nav> <h1 id="firstHeading" class="firstHeading mw-first-heading"><span class="mw-page-title-main">QCD matter</span></h1> <div id="p-lang-btn" class="vector-dropdown mw-portlet mw-portlet-lang" > <input type="checkbox" id="p-lang-btn-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-p-lang-btn" class="vector-dropdown-checkbox mw-interlanguage-selector" aria-label="Go to an article in another language. Available in 9 languages" > <label id="p-lang-btn-label" for="p-lang-btn-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--action-progressive mw-portlet-lang-heading-9" aria-hidden="true" ><span class="vector-icon mw-ui-icon-language-progressive mw-ui-icon-wikimedia-language-progressive"></span> <span class="vector-dropdown-label-text">9 languages</span> </label> <div class="vector-dropdown-content"> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li class="interlanguage-link interwiki-ar mw-list-item"><a href="https://ar.wikipedia.org/wiki/%D9%85%D8%A7%D8%AF%D8%A9_%D9%83%D9%88%D8%A7%D8%B1%D9%83%D9%8A%D8%A9" title="مادة كواركية – Arabic" lang="ar" hreflang="ar" data-title="مادة كواركية" data-language-autonym="العربية" data-language-local-name="Arabic" class="interlanguage-link-target"><span>العربية</span></a></li><li class="interlanguage-link interwiki-ca mw-list-item"><a href="https://ca.wikipedia.org/wiki/Mat%C3%A8ria_QCD" title="Matèria QCD – Catalan" lang="ca" hreflang="ca" data-title="Matèria QCD" data-language-autonym="Català" data-language-local-name="Catalan" class="interlanguage-link-target"><span>Català</span></a></li><li class="interlanguage-link interwiki-hi mw-list-item"><a href="https://hi.wikipedia.org/wiki/%E0%A4%95%E0%A5%8D%E0%A4%B5%E0%A4%BE%E0%A4%B0%E0%A5%8D%E0%A4%95_%E0%A4%AA%E0%A4%A6%E0%A4%BE%E0%A4%B0%E0%A5%8D%E0%A4%A5" title="क्वार्क पदार्थ – Hindi" lang="hi" hreflang="hi" data-title="क्वार्क पदार्थ" data-language-autonym="हिन्दी" data-language-local-name="Hindi" class="interlanguage-link-target"><span>हिन्दी</span></a></li><li class="interlanguage-link interwiki-id mw-list-item"><a href="https://id.wikipedia.org/wiki/Zat_kuark" title="Zat kuark – Indonesian" lang="id" hreflang="id" data-title="Zat kuark" data-language-autonym="Bahasa Indonesia" data-language-local-name="Indonesian" class="interlanguage-link-target"><span>Bahasa Indonesia</span></a></li><li class="interlanguage-link interwiki-it mw-list-item"><a href="https://it.wikipedia.org/wiki/Materia_di_quark" title="Materia di quark – Italian" lang="it" hreflang="it" data-title="Materia di quark" data-language-autonym="Italiano" data-language-local-name="Italian" class="interlanguage-link-target"><span>Italiano</span></a></li><li class="interlanguage-link interwiki-pt mw-list-item"><a href="https://pt.wikipedia.org/wiki/Mat%C3%A9ria_QCD" title="Matéria QCD – Portuguese" lang="pt" hreflang="pt" data-title="Matéria QCD" data-language-autonym="Português" data-language-local-name="Portuguese" class="interlanguage-link-target"><span>Português</span></a></li><li class="interlanguage-link interwiki-th mw-list-item"><a href="https://th.wikipedia.org/wiki/%E0%B8%AA%E0%B8%AA%E0%B8%B2%E0%B8%A3%E0%B8%84%E0%B8%A7%E0%B8%B2%E0%B8%A3%E0%B9%8C%E0%B8%81" title="สสารควาร์ก – Thai" lang="th" hreflang="th" data-title="สสารควาร์ก" data-language-autonym="ไทย" data-language-local-name="Thai" class="interlanguage-link-target"><span>ไทย</span></a></li><li class="interlanguage-link interwiki-tr mw-list-item"><a href="https://tr.wikipedia.org/wiki/Kuark_maddesi" title="Kuark maddesi – Turkish" lang="tr" hreflang="tr" data-title="Kuark maddesi" data-language-autonym="Türkçe" data-language-local-name="Turkish" class="interlanguage-link-target"><span>Türkçe</span></a></li><li class="interlanguage-link interwiki-vi mw-list-item"><a href="https://vi.wikipedia.org/wiki/V%E1%BA%ADt_ch%E1%BA%A5t_quark" title="Vật chất quark – Vietnamese" lang="vi" hreflang="vi" data-title="Vật chất quark" data-language-autonym="Tiếng Việt" data-language-local-name="Vietnamese" class="interlanguage-link-target"><span>Tiếng Việt</span></a></li> </ul> <div class="after-portlet after-portlet-lang"><span class="wb-langlinks-edit wb-langlinks-link"><a href="https://www.wikidata.org/wiki/Special:EntityPage/Q2755153#sitelinks-wikipedia" title="Edit interlanguage links" class="wbc-editpage">Edit links</a></span></div> </div> </div> </div> </header> <div class="vector-page-toolbar"> <div class="vector-page-toolbar-container"> <div id="left-navigation"> <nav aria-label="Namespaces"> <div id="p-associated-pages" class="vector-menu vector-menu-tabs mw-portlet mw-portlet-associated-pages" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="ca-nstab-main" class="selected vector-tab-noicon mw-list-item"><a href="/wiki/QCD_matter" title="View the content page [c]" accesskey="c"><span>Article</span></a></li><li id="ca-talk" class="vector-tab-noicon mw-list-item"><a href="/wiki/Talk:QCD_matter" rel="discussion" title="Discuss improvements to the content page [t]" accesskey="t"><span>Talk</span></a></li> </ul> </div> </div> <div id="vector-variants-dropdown" class="vector-dropdown emptyPortlet" > <input type="checkbox" id="vector-variants-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-variants-dropdown" class="vector-dropdown-checkbox " aria-label="Change language variant" > <label id="vector-variants-dropdown-label" for="vector-variants-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet" aria-hidden="true" ><span class="vector-dropdown-label-text">English</span> </label> <div class="vector-dropdown-content"> <div id="p-variants" class="vector-menu mw-portlet mw-portlet-variants emptyPortlet" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> </ul> </div> </div> </div> </div> </nav> </div> <div id="right-navigation" class="vector-collapsible"> <nav aria-label="Views"> <div id="p-views" class="vector-menu vector-menu-tabs mw-portlet mw-portlet-views" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="ca-view" class="selected vector-tab-noicon mw-list-item"><a href="/wiki/QCD_matter"><span>Read</span></a></li><li id="ca-edit" class="vector-tab-noicon mw-list-item"><a href="/w/index.php?title=QCD_matter&action=edit" title="Edit this page [e]" accesskey="e"><span>Edit</span></a></li><li id="ca-history" class="vector-tab-noicon mw-list-item"><a href="/w/index.php?title=QCD_matter&action=history" title="Past revisions of this page [h]" accesskey="h"><span>View history</span></a></li> </ul> </div> </div> </nav> <nav class="vector-page-tools-landmark" aria-label="Page tools"> <div id="vector-page-tools-dropdown" class="vector-dropdown vector-page-tools-dropdown" > <input type="checkbox" id="vector-page-tools-dropdown-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-page-tools-dropdown" class="vector-dropdown-checkbox " aria-label="Tools" > <label id="vector-page-tools-dropdown-label" for="vector-page-tools-dropdown-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet" aria-hidden="true" ><span class="vector-dropdown-label-text">Tools</span> </label> <div class="vector-dropdown-content"> <div id="vector-page-tools-unpinned-container" class="vector-unpinned-container"> <div id="vector-page-tools" class="vector-page-tools vector-pinnable-element"> <div class="vector-pinnable-header vector-page-tools-pinnable-header vector-pinnable-header-unpinned" data-feature-name="page-tools-pinned" data-pinnable-element-id="vector-page-tools" data-pinned-container-id="vector-page-tools-pinned-container" data-unpinned-container-id="vector-page-tools-unpinned-container" > <div class="vector-pinnable-header-label">Tools</div> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-page-tools.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-page-tools.unpin">hide</button> </div> <div id="p-cactions" class="vector-menu mw-portlet mw-portlet-cactions emptyPortlet vector-has-collapsible-items" title="More options" > <div class="vector-menu-heading"> Actions </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="ca-more-view" class="selected vector-more-collapsible-item mw-list-item"><a href="/wiki/QCD_matter"><span>Read</span></a></li><li id="ca-more-edit" class="vector-more-collapsible-item mw-list-item"><a href="/w/index.php?title=QCD_matter&action=edit" title="Edit this page [e]" accesskey="e"><span>Edit</span></a></li><li id="ca-more-history" class="vector-more-collapsible-item mw-list-item"><a href="/w/index.php?title=QCD_matter&action=history"><span>View history</span></a></li> </ul> </div> </div> <div id="p-tb" class="vector-menu mw-portlet mw-portlet-tb" > <div class="vector-menu-heading"> General </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="t-whatlinkshere" class="mw-list-item"><a href="/wiki/Special:WhatLinksHere/QCD_matter" title="List of all English Wikipedia pages containing links to this page [j]" accesskey="j"><span>What links here</span></a></li><li id="t-recentchangeslinked" class="mw-list-item"><a href="/wiki/Special:RecentChangesLinked/QCD_matter" rel="nofollow" title="Recent changes in pages linked from this page [k]" accesskey="k"><span>Related changes</span></a></li><li id="t-upload" class="mw-list-item"><a href="/wiki/Wikipedia:File_Upload_Wizard" title="Upload files [u]" accesskey="u"><span>Upload file</span></a></li><li id="t-specialpages" class="mw-list-item"><a href="/wiki/Special:SpecialPages" title="A list of all special pages [q]" accesskey="q"><span>Special pages</span></a></li><li id="t-permalink" class="mw-list-item"><a href="/w/index.php?title=QCD_matter&oldid=1216611248" title="Permanent link to this revision of this page"><span>Permanent link</span></a></li><li id="t-info" class="mw-list-item"><a href="/w/index.php?title=QCD_matter&action=info" title="More information about this page"><span>Page information</span></a></li><li id="t-cite" class="mw-list-item"><a href="/w/index.php?title=Special:CiteThisPage&page=QCD_matter&id=1216611248&wpFormIdentifier=titleform" title="Information on how to cite this page"><span>Cite this page</span></a></li><li id="t-urlshortener" class="mw-list-item"><a href="/w/index.php?title=Special:UrlShortener&url=https%3A%2F%2Fen.wikipedia.org%2Fwiki%2FQCD_matter"><span>Get shortened URL</span></a></li><li id="t-urlshortener-qrcode" class="mw-list-item"><a href="/w/index.php?title=Special:QrCode&url=https%3A%2F%2Fen.wikipedia.org%2Fwiki%2FQCD_matter"><span>Download QR code</span></a></li> </ul> </div> </div> <div id="p-coll-print_export" class="vector-menu mw-portlet mw-portlet-coll-print_export" > <div class="vector-menu-heading"> Print/export </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="coll-download-as-rl" class="mw-list-item"><a href="/w/index.php?title=Special:DownloadAsPdf&page=QCD_matter&action=show-download-screen" title="Download this page as a PDF file"><span>Download as PDF</span></a></li><li id="t-print" class="mw-list-item"><a href="/w/index.php?title=QCD_matter&printable=yes" title="Printable version of this page [p]" accesskey="p"><span>Printable version</span></a></li> </ul> </div> </div> <div id="p-wikibase-otherprojects" class="vector-menu mw-portlet mw-portlet-wikibase-otherprojects" > <div class="vector-menu-heading"> In other projects </div> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="t-wikibase" class="wb-otherproject-link wb-otherproject-wikibase-dataitem mw-list-item"><a href="https://www.wikidata.org/wiki/Special:EntityPage/Q2755153" title="Structured data on this page hosted by Wikidata [g]" accesskey="g"><span>Wikidata item</span></a></li> </ul> </div> </div> </div> </div> </div> </div> </nav> </div> </div> </div> <div class="vector-column-end"> <div class="vector-sticky-pinned-container"> <nav class="vector-page-tools-landmark" aria-label="Page tools"> <div id="vector-page-tools-pinned-container" class="vector-pinned-container"> </div> </nav> <nav class="vector-appearance-landmark" aria-label="Appearance"> <div id="vector-appearance-pinned-container" class="vector-pinned-container"> <div id="vector-appearance" class="vector-appearance vector-pinnable-element"> <div class="vector-pinnable-header vector-appearance-pinnable-header vector-pinnable-header-pinned" data-feature-name="appearance-pinned" data-pinnable-element-id="vector-appearance" data-pinned-container-id="vector-appearance-pinned-container" data-unpinned-container-id="vector-appearance-unpinned-container" > <div class="vector-pinnable-header-label">Appearance</div> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-pin-button" data-event-name="pinnable-header.vector-appearance.pin">move to sidebar</button> <button class="vector-pinnable-header-toggle-button vector-pinnable-header-unpin-button" data-event-name="pinnable-header.vector-appearance.unpin">hide</button> </div> </div> </div> </nav> </div> </div> <div id="bodyContent" class="vector-body" aria-labelledby="firstHeading" data-mw-ve-target-container> <div class="vector-body-before-content"> <div class="mw-indicators"> </div> <div id="siteSub" class="noprint">From Wikipedia, the free encyclopedia</div> </div> <div id="contentSub"><div id="mw-content-subtitle"><span class="mw-redirectedfrom">(Redirected from <a href="/w/index.php?title=Quark_matter&redirect=no" class="mw-redirect" title="Quark matter">Quark matter</a>)</span></div></div> <div id="mw-content-text" class="mw-body-content"><div class="mw-content-ltr mw-parser-output" lang="en" dir="ltr"><div class="shortdescription nomobile noexcerpt noprint searchaux" style="display:none">Hypothetical phases of matter</div> <p><b>Quark matter</b> or <b>QCD matter</b> (<a href="/wiki/Quantum_chromodynamics" title="Quantum chromodynamics">quantum chromodynamic</a>) refers to any of a number of hypothetical <a href="/wiki/Phase_(matter)" title="Phase (matter)">phases</a> of matter whose <a href="/wiki/Degrees_of_freedom_(physics_and_chemistry)" title="Degrees of freedom (physics and chemistry)">degrees of freedom</a> include <a href="/wiki/Quark" title="Quark">quarks</a> and <a href="/wiki/Gluon" title="Gluon">gluons</a>, of which the prominent example is <a href="/wiki/Quark%E2%80%93gluon_plasma" title="Quark–gluon plasma">quark-gluon plasma</a>.<sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> Several series of conferences in 2019, 2020, and 2021 were devoted to this topic.<sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-3" class="reference"><a href="#cite_note-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> </p><p>Quarks are liberated into quark matter at extremely high temperatures and/or densities, and some of them are still only theoretical as they require conditions so extreme that they cannot be produced in any laboratory, especially not at equilibrium conditions. Under these extreme conditions, the familiar structure of <a href="/wiki/Matter" title="Matter">matter</a>, where the basic constituents are <a href="/wiki/Atomic_nucleus" title="Atomic nucleus">nuclei</a> (consisting of <a href="/wiki/Nucleon" title="Nucleon">nucleons</a> which are bound states of quarks) and electrons, is disrupted. In quark matter it is more appropriate to treat the quarks themselves as the basic degrees of freedom. </p><p>In the <a href="/wiki/Standard_model" class="mw-redirect" title="Standard model">standard model</a> of particle physics, the <a href="/wiki/Strong_interaction" title="Strong interaction">strong force</a> is described by the theory of <a href="/wiki/Quantum_chromodynamics" title="Quantum chromodynamics">QCD</a>. At ordinary temperatures or densities this force just <a href="/wiki/Color_confinement" title="Color confinement">confines</a> the quarks into composite particles (<a href="/wiki/Hadrons" class="mw-redirect" title="Hadrons">hadrons</a>) of size around 10<sup>−15</sup> m = 1 <a href="/wiki/Femtometer" class="mw-redirect" title="Femtometer">femtometer</a> = 1 fm (corresponding to the QCD energy scale Λ<sub>QCD</sub> ≈ 200 <a href="/wiki/MeV" class="mw-redirect" title="MeV">MeV</a>) and its effects are not noticeable at longer distances. </p><p>However, when the temperature reaches the QCD energy scale (<a href="/wiki/Electronvolt" title="Electronvolt">T</a> of order 10<sup>12</sup> <a href="/wiki/Kelvin" title="Kelvin">kelvins</a>) or the density rises to the point where the average inter-quark separation is less than 1 fm (quark <a href="/wiki/Chemical_potential" title="Chemical potential">chemical potential</a> μ around 400 MeV), the hadrons are melted into their constituent quarks, and the strong interaction becomes the dominant feature of the physics. Such phases are called quark matter or QCD matter. </p><p>The strength of the color force makes the properties of quark matter unlike gas or plasma, instead leading to a state of matter more reminiscent of a liquid. At high densities, quark matter is a <a href="/wiki/Fermi_liquid_theory" title="Fermi liquid theory">Fermi liquid</a>, but is predicted to exhibit <a href="/wiki/Color_superconductivity" title="Color superconductivity">color superconductivity</a> at high densities and temperatures below 10<sup>12</sup> K. </p> <style data-mw-deduplicate="TemplateStyles:r1233989161">.mw-parser-output .unsolved{margin:0.5em 0 1em 1em;border:#ccc solid;padding:0.35em 0.35em 0.35em 2.2em;background-color:var(--background-color-interactive-subtle);background-image:url("https://upload.wikimedia.org/wikipedia/commons/2/26/Question%2C_Web_Fundamentals.svg");background-position:top 50%left 0.35em;background-size:1.5em;background-repeat:no-repeat}@media(min-width:720px){.mw-parser-output .unsolved{clear:right;float:right;max-width:25%}}.mw-parser-output .unsolved-label{font-weight:bold}.mw-parser-output .unsolved-body{margin:0.35em;font-style:italic}.mw-parser-output .unsolved-more{font-size:smaller}</style> <div role="note" aria-labelledby="unsolved-label-physics" class="unsolved"> <div><span class="unsolved-label" id="unsolved-label-physics">Unsolved problem in physics</span>:</div> <div class="unsolved-body">QCD in the non-<a href="/wiki/Perturbation_theory_(quantum_mechanics)" title="Perturbation theory (quantum mechanics)">perturbative</a> regime: <b>quark matter</b>. The equations of QCD predict that a <a href="/wiki/Quark%E2%80%93gluon_plasma" title="Quark–gluon plasma">sea of quarks and gluons</a> should be formed at high temperature and density. What are the properties of this <a href="/wiki/Phase_of_matter" class="mw-redirect" title="Phase of matter">phase of matter</a>?</div> <div class="unsolved-more"><a href="/wiki/List_of_unsolved_problems_in_physics" title="List of unsolved problems in physics">(more unsolved problems in physics)</a></div> </div> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Occurrence">Occurrence</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=QCD_matter&action=edit&section=1" title="Edit section: Occurrence"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <div class="mw-heading mw-heading3"><h3 id="Natural_occurrence">Natural occurrence</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=QCD_matter&action=edit&section=2" title="Edit section: Natural occurrence"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li>According to the <a href="/wiki/Big_Bang" title="Big Bang">Big Bang</a> theory, in the early universe at high temperatures when the universe was only a few tens of microseconds old, the phase of matter took the form of a hot phase of quark matter called the <a href="/wiki/Quark%E2%80%93gluon_plasma" title="Quark–gluon plasma">quark–gluon plasma</a> (QGP).<sup id="cite_ref-5" class="reference"><a href="#cite_note-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup></li> <li><a href="/wiki/Compact_star" class="mw-redirect" title="Compact star">Compact stars</a> (<a href="/wiki/Neutron_star" title="Neutron star">neutron stars</a>). A neutron star is much cooler than 10<sup>12</sup> K, but gravitational collapse has compressed it to such high densities, that it is reasonable to surmise that quark matter may exist in the core.<sup id="cite_ref-6" class="reference"><a href="#cite_note-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> Compact stars composed mostly or entirely of quark matter are called <a href="/wiki/Quark_star" title="Quark star">quark stars</a> or <a href="/wiki/Strange_star" title="Strange star">strange stars</a>.</li> <li>QCD matter may exist within the <a href="/wiki/Hypernova" title="Hypernova">collapsar</a> of a <a href="/wiki/Gamma-ray_burst" title="Gamma-ray burst">gamma-ray burst</a>, where temperatures as high as 6.7 × 10<sup>13</sup> K may be generated.</li></ul> <p>At this time no star with properties expected of these objects has been observed, although some evidence has been provided for quark matter in the cores of large neutron stars.<sup id="cite_ref-:0_7-0" class="reference"><a href="#cite_note-:0-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup> </p> <ul><li><a href="/wiki/Strangelet" title="Strangelet">Strangelets</a>. These are theoretically postulated (but as yet unobserved) lumps of <a href="/wiki/Strange_matter" title="Strange matter">strange matter</a> comprising nearly equal amounts of up, down and strange quarks. Strangelets are supposed to be present in the galactic flux of high energy particles and should therefore theoretically be detectable in <a href="/wiki/Cosmic_rays" class="mw-redirect" title="Cosmic rays">cosmic rays</a> here on Earth, but no strangelet has been detected with certainty.<sup id="cite_ref-8" class="reference"><a href="#cite_note-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-9" class="reference"><a href="#cite_note-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup></li> <li><a href="/wiki/Cosmic_ray" title="Cosmic ray">Cosmic ray</a> impacts. Cosmic rays comprise a lot of different particles, including highly accelerated atomic nuclei, particularly that of <a href="/wiki/Iron" title="Iron">iron</a>.</li></ul> <p>Laboratory experiments suggests that the inevitable interaction with heavy <a href="/wiki/Noble_gas" title="Noble gas">noble gas</a> nuclei in the <a href="/wiki/Upper_atmosphere" title="Upper atmosphere">upper atmosphere</a> would lead to quark–gluon plasma formation. </p> <ul><li>Quark matter with <a href="/wiki/Baryon_number" title="Baryon number">baryon number</a> over about 300 may be more stable than nuclear matter. This form of baryonic matter could possibly form a <a href="/wiki/Continent_of_stability" title="Continent of stability">continent of stability</a>.<sup id="cite_ref-10" class="reference"><a href="#cite_note-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup></li></ul> <div class="mw-heading mw-heading3"><h3 id="Laboratory_experiments">Laboratory experiments</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=QCD_matter&action=edit&section=3" title="Edit section: Laboratory experiments"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-default-size" typeof="mw:File/Thumb"><a href="/wiki/File:Alicelead3.jpg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/3/3c/Alicelead3.jpg/220px-Alicelead3.jpg" decoding="async" width="220" height="156" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/3/3c/Alicelead3.jpg/330px-Alicelead3.jpg 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/3/3c/Alicelead3.jpg/440px-Alicelead3.jpg 2x" data-file-width="1496" data-file-height="1060" /></a><figcaption>Particle debris trajectories from one of the first lead-ion collisions with the LHC, as recorded by the <a href="/wiki/ALICE:_A_Large_Ion_Collider_Experiment" class="mw-redirect" title="ALICE: A Large Ion Collider Experiment">ALICE</a> detector. The extremely brief appearance of quark matter in the point of collision is inferred from the statistics of the trajectories.</figcaption></figure> <p>Even though quark-gluon plasma can only occur under quite extreme conditions of temperature and/or pressure, it is being actively studied at <a href="/wiki/Particle_collider" class="mw-redirect" title="Particle collider">particle colliders</a>, such as the Large Hadron Collider <a href="/wiki/Large_Hadron_Collider" title="Large Hadron Collider">LHC</a> at <a href="/wiki/CERN" title="CERN">CERN</a> and the Relativistic Heavy Ion Collider <a href="/wiki/Relativistic_Heavy_Ion_Collider" title="Relativistic Heavy Ion Collider">RHIC</a> at <a href="/wiki/Brookhaven_National_Laboratory" title="Brookhaven National Laboratory">Brookhaven National Laboratory</a>. </p><p>In these collisions, the plasma only occurs for a very short time before it spontaneously disintegrates. The plasma's physical characteristics are studied by detecting the debris emanating from the collision region with large particle detectors <sup id="cite_ref-11" class="reference"><a href="#cite_note-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-12" class="reference"><a href="#cite_note-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup> </p><p><a href="/wiki/Heavy-ion_collisions" class="mw-redirect" title="Heavy-ion collisions">Heavy-ion collisions</a> at very high energies can produce small short-lived regions of space whose energy density is comparable to that of the <a href="/wiki/Chronology_of_the_universe#The_quark_epoch" title="Chronology of the universe">20-micro-second-old universe</a>. This has been achieved by colliding heavy nuclei such as <a href="/wiki/Lead" title="Lead">lead</a> nuclei at high speeds, and a first time claim of formation of <a href="/wiki/Quark%E2%80%93gluon_plasma" title="Quark–gluon plasma">quark–gluon plasma</a> came from the <a href="/wiki/Super_Proton_Synchrotron" title="Super Proton Synchrotron">SPS</a> accelerator at <a href="/wiki/CERN" title="CERN">CERN</a> in February 2000.<sup id="cite_ref-13" class="reference"><a href="#cite_note-13"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup> </p><p>This work has been continued at more powerful accelerators, such as RHIC in the US, and as of 2010 at the European LHC at CERN located in the border area of Switzerland and France. There is good evidence that the quark–gluon plasma has also been produced at RHIC.<sup id="cite_ref-14" class="reference"><a href="#cite_note-14"><span class="cite-bracket">[</span>14<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Thermodynamics">Thermodynamics</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=QCD_matter&action=edit&section=4" title="Edit section: Thermodynamics"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The context for understanding the thermodynamics of quark matter is the <a href="/wiki/Standard_model" class="mw-redirect" title="Standard model">standard model</a> of particle physics, which contains six different <a href="/wiki/Flavor_(particle_physics)" class="mw-redirect" title="Flavor (particle physics)">flavors</a> of quarks, as well as <a href="/wiki/Lepton" title="Lepton">leptons</a> like <a href="/wiki/Electron" title="Electron">electrons</a> and <a href="/wiki/Neutrino" title="Neutrino">neutrinos</a>. These interact via the <a href="/wiki/Strong_interaction" title="Strong interaction">strong interaction</a>, <a href="/wiki/Electromagnetism" title="Electromagnetism">electromagnetism</a>, and also the <a href="/wiki/Weak_interaction" title="Weak interaction">weak interaction</a> which allows one flavor of quark to turn into another. Electromagnetic interactions occur between particles that carry electrical charge; strong interactions occur between particles that carry <a href="/wiki/Color_charge" title="Color charge">color charge</a>. </p><p>The correct thermodynamic treatment of quark matter depends on the physical context. For large quantities that exist for long periods of time (the "thermodynamic limit"), we must take into account the fact that the only conserved charges in the standard model are quark number (equivalent to <a href="/wiki/Baryon" title="Baryon">baryon</a> number), electric charge, the eight color charges, and lepton number. Each of these can have an associated chemical potential. However, large volumes of matter must be electrically and color-neutral, which determines the electric and color charge chemical potentials. This leaves a three-dimensional <a href="/wiki/Phase_space" title="Phase space">phase space</a>, parameterized by quark chemical potential, lepton chemical potential, and temperature. </p><p>In compact stars quark matter would occupy cubic kilometers and exist for millions of years, so the thermodynamic limit is appropriate. However, the neutrinos escape, violating lepton number, so the phase space for quark matter in compact stars only has two dimensions, temperature (<i>T</i>) and quark number chemical potential μ. A <a href="/wiki/Strangelet" title="Strangelet">strangelet</a> is not in the thermodynamic limit of large volume, so it is like an exotic nucleus: it may carry electric charge. </p><p>A heavy-ion collision is in neither the thermodynamic limit of large volumes nor long times. Putting aside questions of whether it is sufficiently equilibrated for thermodynamics to be applicable, there is certainly not enough time for weak interactions to occur, so flavor is conserved, and there are independent chemical potentials for all six quark flavors. The initial conditions (the <a href="/wiki/Impact_parameter" title="Impact parameter">impact parameter</a> of the collision, the number of up and down quarks in the colliding nuclei, and the fact that they contain no quarks of other flavors) determine the chemical potentials. (Reference for this section:<sup id="cite_ref-RMP_15-0" class="reference"><a href="#cite_note-RMP-15"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Rischke_16-0" class="reference"><a href="#cite_note-Rischke-16"><span class="cite-bracket">[</span>16<span class="cite-bracket">]</span></a></sup>). </p> <div class="mw-heading mw-heading2"><h2 id="Phase_diagram">Phase diagram</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=QCD_matter&action=edit&section=5" title="Edit section: Phase diagram"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <figure class="mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/File:QCD_phase_diagram.png" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/8/8f/QCD_phase_diagram.png/300px-QCD_phase_diagram.png" decoding="async" width="300" height="230" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/8/8f/QCD_phase_diagram.png/450px-QCD_phase_diagram.png 1.5x, //upload.wikimedia.org/wikipedia/commons/8/8f/QCD_phase_diagram.png 2x" data-file-width="457" data-file-height="350" /></a><figcaption>Conjectured form of the phase diagram of QCD matter, with temperature on the vertical axis and quark <a href="/wiki/Chemical_potential" title="Chemical potential">chemical potential</a> on the horizontal axis, both in mega-<a href="/wiki/Electron_volt" class="mw-redirect" title="Electron volt">electron volts</a>.<sup id="cite_ref-RMP_15-1" class="reference"><a href="#cite_note-RMP-15"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup></figcaption></figure> <p>The <a href="/wiki/Phase_diagram" title="Phase diagram">phase diagram</a> of quark matter is not well known, either experimentally or theoretically. A commonly conjectured form of the phase diagram is shown in the figure to the right.<sup id="cite_ref-RMP_15-2" class="reference"><a href="#cite_note-RMP-15"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup> It is applicable to matter in a compact star, where the only relevant thermodynamic potentials are quark <a href="/wiki/Chemical_potential#Fundamental_particle_chemical_potential" title="Chemical potential">chemical potential</a> μ and <a href="/wiki/Temperature" title="Temperature">temperature</a> T. </p><p>For guidance it also shows the typical values of μ and <i>T</i> in heavy-ion collisions and in the early universe. For readers who are not familiar with the concept of a chemical potential, it is helpful to think of μ as a measure of the imbalance between quarks and antiquarks in the system. Higher μ means a stronger bias favoring quarks over antiquarks. At low temperatures there are no antiquarks, and then higher μ generally means a higher density of quarks. </p><p>Ordinary atomic matter as we know it is really a mixed phase, droplets of nuclear matter (nuclei) surrounded by vacuum, which exists at the low-temperature phase boundary between vacuum and nuclear matter, at μ = 310 MeV and <i>T</i> close to zero. If we increase the quark density (i.e. increase μ) keeping the temperature low, we move into a phase of more and more compressed nuclear matter. Following this path corresponds to burrowing more and more deeply into a <a href="/wiki/Neutron_star" title="Neutron star">neutron star</a>. </p><p>Eventually, at an unknown critical value of μ, there is a transition to quark matter. At ultra-high densities we expect to find the <a href="/wiki/Color-flavor_locking" class="mw-redirect" title="Color-flavor locking">color-flavor-locked</a> (CFL) phase of <a href="/wiki/Color_superconductivity" title="Color superconductivity">color-superconducting</a> quark matter. At intermediate densities we expect some other phases (labelled "non-CFL quark liquid" in the figure) whose nature is presently unknown.<sup id="cite_ref-RMP_15-3" class="reference"><a href="#cite_note-RMP-15"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Rischke_16-1" class="reference"><a href="#cite_note-Rischke-16"><span class="cite-bracket">[</span>16<span class="cite-bracket">]</span></a></sup> They might be other forms of color-superconducting quark matter, or something different. </p><p>Now, imagine starting at the bottom left corner of the phase diagram, in the vacuum where μ = <i>T</i> = 0. If we heat up the system without introducing any preference for quarks over antiquarks, this corresponds to moving vertically upwards along the <i>T</i> axis. At first, quarks are still confined and we create a gas of hadrons (<a href="/wiki/Pion" title="Pion">pions</a>, mostly). Then around <i>T</i> = 150 MeV there is a crossover to the quark gluon plasma: thermal fluctuations break up the pions, and we find a gas of quarks, antiquarks, and gluons, as well as lighter particles such as photons, electrons, positrons, etc. Following this path corresponds to travelling far back in time (so to say), to the state of the universe shortly after the big bang (where there was a very tiny preference for quarks over antiquarks). </p><p>The line that rises up from the nuclear/quark matter transition and then bends back towards the <i>T</i> axis, with its end marked by a star, is the conjectured boundary between confined and unconfined phases. Until recently it was also believed to be a boundary between phases where chiral symmetry is broken (low temperature and density) and phases where it is unbroken (high temperature and density). It is now known that the CFL phase exhibits chiral symmetry breaking, and other quark matter phases may also break chiral symmetry, so it is not clear whether this is really a chiral transition line. The line ends at the "chiral <a href="/wiki/Critical_point_(thermodynamics)" title="Critical point (thermodynamics)">critical point</a>", marked by a star in this figure, which is a special temperature and density at which striking physical phenomena, analogous to <a href="/wiki/Critical_opalescence" title="Critical opalescence">critical opalescence</a>, are expected. (Reference for this section:<sup id="cite_ref-RMP_15-4" class="reference"><a href="#cite_note-RMP-15"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-Rischke_16-2" class="reference"><a href="#cite_note-Rischke-16"><span class="cite-bracket">[</span>16<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-TS_17-0" class="reference"><a href="#cite_note-TS-17"><span class="cite-bracket">[</span>17<span class="cite-bracket">]</span></a></sup>). </p><p>For a complete description of phase diagram it is required that one must have complete understanding of dense, strongly interacting hadronic matter and strongly interacting quark matter from some underlying theory e.g. quantum chromodynamics (QCD). However, because such a description requires the proper understanding of QCD in its non-perturbative regime, which is still far from being completely understood, any theoretical advance remains very challenging. </p> <div class="mw-heading mw-heading2"><h2 id="Theoretical_challenges:_calculation_techniques">Theoretical challenges: calculation techniques</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=QCD_matter&action=edit&section=6" title="Edit section: Theoretical challenges: calculation techniques"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The phase structure of quark matter remains mostly conjectural because it is difficult to perform calculations predicting the properties of quark matter. The reason is that QCD, the theory describing the dominant interaction between quarks, is strongly coupled at the densities and temperatures of greatest physical interest, and hence it is very hard to obtain any predictions from it. Here are brief descriptions of some of the standard approaches. </p> <div class="mw-heading mw-heading3"><h3 id="Lattice_gauge_theory">Lattice gauge theory</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=QCD_matter&action=edit&section=7" title="Edit section: Lattice gauge theory"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The only first-principles calculational tool currently available is <a href="/wiki/Lattice_QCD" title="Lattice QCD">lattice QCD</a>, i.e. brute-force computer calculations. Because of a technical obstacle known as the fermion <a href="/wiki/Sign_problem" class="mw-redirect" title="Sign problem">sign problem</a>, this method can only be used at low density and high temperature (μ < <i>T</i>), and it predicts that the crossover to the quark–gluon plasma will occur around <i>T</i> = 150 MeV <sup id="cite_ref-18" class="reference"><a href="#cite_note-18"><span class="cite-bracket">[</span>18<span class="cite-bracket">]</span></a></sup> However, it cannot be used to investigate the interesting color-superconducting phase structure at high density and low temperature.<sup id="cite_ref-19" class="reference"><a href="#cite_note-19"><span class="cite-bracket">[</span>19<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Weak_coupling_theory">Weak coupling theory</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=QCD_matter&action=edit&section=8" title="Edit section: Weak coupling theory"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Because QCD is <a href="/wiki/Asymptotic_freedom" title="Asymptotic freedom">asymptotically free</a> it becomes weakly coupled at unrealistically high densities, and diagrammatic methods can be used.<sup id="cite_ref-Rischke_16-3" class="reference"><a href="#cite_note-Rischke-16"><span class="cite-bracket">[</span>16<span class="cite-bracket">]</span></a></sup> Such methods show that the CFL phase occurs at very high density. At high temperatures, however, diagrammatic methods are still not under full control. </p> <div class="mw-heading mw-heading3"><h3 id="Models">Models</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=QCD_matter&action=edit&section=9" title="Edit section: Models"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>To obtain a rough idea of what phases might occur, one can use a model that has some of the same properties as QCD, but is easier to manipulate. Many physicists use <a href="/wiki/Nambu%E2%80%93Jona-Lasinio_model" title="Nambu–Jona-Lasinio model">Nambu–Jona-Lasinio models</a>, which contain no gluons, and replace the strong interaction with a <a href="/wiki/Four-fermion_interaction" class="mw-redirect" title="Four-fermion interaction">four-fermion interaction</a>. Mean-field methods are commonly used to analyse the phases. Another approach is the <a href="/wiki/Bag_model" class="mw-redirect" title="Bag model">bag model</a>, in which the effects of confinement are simulated by an additive energy density that penalizes unconfined quark matter. </p> <div class="mw-heading mw-heading3"><h3 id="Effective_theories">Effective theories</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=QCD_matter&action=edit&section=10" title="Edit section: Effective theories"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Many physicists simply give up on a microscopic approach, and make informed guesses of the expected phases (perhaps based on NJL model results). For each phase, they then write down an effective theory for the low-energy excitations, in terms of a small number of parameters, and use it to make predictions that could allow those parameters to be fixed by experimental observations.<sup id="cite_ref-TS_17-1" class="reference"><a href="#cite_note-TS-17"><span class="cite-bracket">[</span>17<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading3"><h3 id="Other_approaches">Other approaches</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=QCD_matter&action=edit&section=11" title="Edit section: Other approaches"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1236090951">.mw-parser-output .hatnote{font-style:italic}.mw-parser-output div.hatnote{padding-left:1.6em;margin-bottom:0.5em}.mw-parser-output .hatnote i{font-style:normal}.mw-parser-output .hatnote+link+.hatnote{margin-top:-0.5em}@media print{body.ns-0 .mw-parser-output .hatnote{display:none!important}}</style><div role="note" class="hatnote navigation-not-searchable">Main article: <a href="/wiki/AdS/QCD" class="mw-redirect" title="AdS/QCD">AdS/QCD</a></div> <p>There are other methods that are sometimes used to shed light on QCD, but for various reasons have not yet yielded useful results in studying quark matter. </p> <div class="mw-heading mw-heading4"><h4 id="1/N_expansion"><span id="1.2FN_expansion"></span>1/N expansion</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=QCD_matter&action=edit&section=12" title="Edit section: 1/N expansion"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Treat the number of colors <i>N</i>, which is actually 3, as a large number, and expand in powers of 1/<i>N</i>. It turns out that at high density the higher-order corrections are large, and the expansion gives misleading results.<sup id="cite_ref-RMP_15-5" class="reference"><a href="#cite_note-RMP-15"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading4"><h4 id="Supersymmetry">Supersymmetry</h4><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=QCD_matter&action=edit&section=13" title="Edit section: Supersymmetry"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Adding scalar quarks (squarks) and fermionic gluons (gluinos) to the theory makes it more tractable, but the thermodynamics of quark matter depends crucially on the fact that only fermions can carry quark number, and on the number of degrees of freedom in general. </p> <div class="mw-heading mw-heading2"><h2 id="Experimental_challenges">Experimental challenges</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=QCD_matter&action=edit&section=14" title="Edit section: Experimental challenges"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Experimentally, it is hard to map the phase diagram of quark matter because it has been rather difficult to learn how to tune to high enough temperatures and density in the laboratory experiment using collisions of relativistic heavy ions as experimental tools. However, these collisions ultimately will provide information about the crossover from <a href="/wiki/Hadron" title="Hadron">hadronic matter</a> to QGP. It has been suggested that the observations of compact stars may also constrain the information about the high-density low-temperature region. Models of the cooling, spin-down, and precession of these stars offer information about the relevant properties of their interior. As observations become more precise, physicists hope to learn more.<sup id="cite_ref-RMP_15-6" class="reference"><a href="#cite_note-RMP-15"><span class="cite-bracket">[</span>15<span class="cite-bracket">]</span></a></sup> </p><p>One of the natural subjects for future research is the search for the exact location of the chiral critical point. Some ambitious lattice QCD calculations may have found evidence for it, and future calculations will clarify the situation. Heavy-ion collisions might be able to measure its position experimentally, but this will require scanning across a range of values of μ and T.<sup id="cite_ref-20" class="reference"><a href="#cite_note-20"><span class="cite-bracket">[</span>20<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Evidence">Evidence</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=QCD_matter&action=edit&section=15" title="Edit section: Evidence"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>In 2020, evidence was provided that the cores of neutron stars with mass ~2<a href="/wiki/Solar_mass" title="Solar mass">M<sub>⊙</sub></a> were likely composed of quark matter.<sup id="cite_ref-:0_7-1" class="reference"><a href="#cite_note-:0-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-21" class="reference"><a href="#cite_note-21"><span class="cite-bracket">[</span>21<span class="cite-bracket">]</span></a></sup> Their result was based on neutron-star <a href="/wiki/Spaghettification" title="Spaghettification">tidal deformability</a> during a <a href="/wiki/Neutron_star_merger" title="Neutron star merger">neutron star merger</a> as measured by <a href="/wiki/Gravitational-wave_observatory" title="Gravitational-wave observatory">gravitational-wave observatories</a>, leading to an estimate of star radius, combined with calculations of the equation of state relating the pressure and energy density of the star's core. The evidence was strongly suggestive but did not conclusively prove the existence of quark matter. </p> <div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=QCD_matter&action=edit&section=16" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/Color%E2%80%93flavor_locking" title="Color–flavor locking">Color–flavor locking</a> – Phenomenon in high-density strange matter</li> <li><a href="/wiki/Lattice_QCD" title="Lattice QCD">Lattice QCD</a> – Quantum chromodynamics on a lattice</li> <li><a href="/wiki/Quantum_chromodynamics" title="Quantum chromodynamics">Quantum chromodynamics</a> – Theory of the strong nuclear interactions</li> <li><a href="/wiki/Quark%E2%80%93gluon_plasma" title="Quark–gluon plasma">Quark–gluon plasma</a> – Phase of quantum chromodynamics (QCD)</li> <li><a href="/wiki/Quark_star" title="Quark star">Quark star</a> – Compact exotic star which forms matter consisting mostly of quarks</li> <li><a href="/wiki/SU(2)_color_superconductivity" title="SU(2) color superconductivity">SU(2) color superconductivity</a> – Property of quark matter</li> <li><a href="/wiki/Strange_matter" title="Strange matter">Strange matter</a> – Degenerate matter made from strange quarks</li> <li><a href="/wiki/Strangeness_and_quark-gluon_plasma" class="mw-redirect" title="Strangeness and quark-gluon plasma">Strangeness and quark-gluon plasma</a> – Subatomic signature<span style="display:none" class="category-annotation-with-redirected-description">Pages displaying short descriptions of redirect targets</span></li> <li><a href="/wiki/1/N_expansion" title="1/N expansion">1/N expansion</a> – Perturbative analysis of quantum field theories</li></ul> <div class="mw-heading mw-heading2"><h2 id="Sources_and_further_reading">Sources and further reading</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=QCD_matter&action=edit&section=17" title="Edit section: Sources and further reading"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li>Aronson, S. and Ludlam, T.: <a rel="nofollow" class="external text" href="https://searchworks.stanford.edu/view/11327941"><i>"Hunting the quark gluon plasma"</i></a>, U.S. Dept. of Energy (2005)</li> <li>Letessier, Jean: <i><a rel="nofollow" class="external text" href="https://searchworks.stanford.edu/view/4807502">Hadrons and quark-gluon plasma</a></i>, Cambridge monographs on particle physics, nuclear physics, and cosmology (Vol. 18), Cambridge University Press (2002)</li> <li><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite id="CITEREFS._Hands2001" class="citation journal cs1">S. Hands (2001). "The phase diagram of QCD". <i>Contemporary Physics</i>. <b>42</b> (4): 209–225. <a href="/wiki/ArXiv_(identifier)" class="mw-redirect" title="ArXiv (identifier)">arXiv</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://arxiv.org/abs/physics/0105022">physics/0105022</a></span>. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/2001ConPh..42..209H">2001ConPh..42..209H</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1080%2F00107510110063843">10.1080/00107510110063843</a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:16835076">16835076</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Contemporary+Physics&rft.atitle=The+phase+diagram+of+QCD&rft.volume=42&rft.issue=4&rft.pages=209-225&rft.date=2001&rft_id=info%3Aarxiv%2Fphysics%2F0105022&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A16835076%23id-name%3DS2CID&rft_id=info%3Adoi%2F10.1080%2F00107510110063843&rft_id=info%3Abibcode%2F2001ConPh..42..209H&rft.au=S.+Hands&rfr_id=info%3Asid%2Fen.wikipedia.org%3AQCD+matter" class="Z3988"></span></li> <li><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFK._Rajagopal2001" class="citation journal cs1">K. Rajagopal (2001). <a rel="nofollow" class="external text" href="http://www.slac.stanford.edu/pubs/beamline/31/2/31-2-rajagopal.pdf">"Free the quarks"</a> <span class="cs1-format">(PDF)</span>. <i><a href="/w/index.php?title=Beam_Line&action=edit&redlink=1" class="new" title="Beam Line (page does not exist)">Beam Line</a></i>. <b>32</b> (2): 9–15.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Beam+Line&rft.atitle=Free+the+quarks&rft.volume=32&rft.issue=2&rft.pages=9-15&rft.date=2001&rft.au=K.+Rajagopal&rft_id=http%3A%2F%2Fwww.slac.stanford.edu%2Fpubs%2Fbeamline%2F31%2F2%2F31-2-rajagopal.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AQCD+matter" class="Z3988"></span></li></ul> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=QCD_matter&action=edit&section=18" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist reflist-columns references-column-width" style="column-width: 30em;"> <ol class="references"> <li id="cite_note-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-1">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFLetessierRafelski2002" class="citation book cs1">Letessier, Jean; Rafelski, Johann (2002). <a rel="nofollow" class="external text" href="https://www.cambridge.org/core/product/identifier/9780511534997/type/book"><i>Hadrons and Quark–Gluon Plasma</i></a> (1 ed.). Cambridge University Press. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1017%2Fcbo9780511534997">10.1017/cbo9780511534997</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-521-38536-7" title="Special:BookSources/978-0-521-38536-7"><bdi>978-0-521-38536-7</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Hadrons+and+Quark%E2%80%93Gluon+Plasma&rft.edition=1&rft.pub=Cambridge+University+Press&rft.date=2002&rft_id=info%3Adoi%2F10.1017%2Fcbo9780511534997&rft.isbn=978-0-521-38536-7&rft.aulast=Letessier&rft.aufirst=Jean&rft.au=Rafelski%2C+Johann&rft_id=https%3A%2F%2Fwww.cambridge.org%2Fcore%2Fproduct%2Fidentifier%2F9780511534997%2Ftype%2Fbook&rfr_id=info%3Asid%2Fen.wikipedia.org%3AQCD+matter" class="Z3988"></span></span> </li> <li id="cite_note-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-2">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://indico.cern.ch/event/895086/">"Quark Matter 2021: The 29th International Conference on Ultrarelativistic Nucleus-Nucleus Collisions"</a>. <i>Indico</i><span class="reference-accessdate">. Retrieved <span class="nowrap">2020-06-26</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=Indico&rft.atitle=Quark+Matter+2021%3A+The+29th+International+Conference+on+Ultrarelativistic+Nucleus-Nucleus+Collisions&rft_id=https%3A%2F%2Findico.cern.ch%2Fevent%2F895086%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AQCD+matter" class="Z3988"></span></span> </li> <li id="cite_note-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-3">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://indico.cern.ch/event/851194/">"CPOD2020 - International Conference on Critical Point and Onset of Deconfinement"</a>. <i>Indico</i>. 4 May 2020<span class="reference-accessdate">. Retrieved <span class="nowrap">2020-06-26</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=Indico&rft.atitle=CPOD2020+-+International+Conference+on+Critical+Point+and+Onset+of+Deconfinement&rft.date=2020-05-04&rft_id=https%3A%2F%2Findico.cern.ch%2Fevent%2F851194%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AQCD+matter" class="Z3988"></span></span> </li> <li id="cite_note-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-4">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://indico.cern.ch/event/755366/">"Strangeness in Quark Matter 2019"</a>. <i>Indico</i>. 9 June 2019<span class="reference-accessdate">. Retrieved <span class="nowrap">2020-06-26</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=Indico&rft.atitle=Strangeness+in+Quark+Matter+2019&rft.date=2019-06-09&rft_id=https%3A%2F%2Findico.cern.ch%2Fevent%2F755366%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AQCD+matter" class="Z3988"></span></span> </li> <li id="cite_note-5"><span class="mw-cite-backlink"><b><a href="#cite_ref-5">^</a></b></span> <span class="reference-text">See <i>"Hadrons and quark-gluon plasma"</i> for example.</span> </li> <li id="cite_note-6"><span class="mw-cite-backlink"><b><a href="#cite_ref-6">^</a></b></span> <span class="reference-text">Shapiro and Teukolsky: <i>Black Holes, White Dwarfs and Neutron Stars: The Physics of Compact Objects</i>, Wiley 2008</span> </li> <li id="cite_note-:0-7"><span class="mw-cite-backlink">^ <a href="#cite_ref-:0_7-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-:0_7-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFAnnalaGordaKurkelaNättilä2020" class="citation journal cs1">Annala, Eemeli; Gorda, Tyler; Kurkela, Aleksi; Nättilä, Joonas; Vuorinen, Aleksi (2020-06-01). <a rel="nofollow" class="external text" href="https://doi.org/10.1038%2Fs41567-020-0914-9">"Evidence for quark-matter cores in massive neutron stars"</a>. <i>Nature Physics</i>. <b>16</b> (9): 907–910. <a href="/wiki/ArXiv_(identifier)" class="mw-redirect" title="ArXiv (identifier)">arXiv</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://arxiv.org/abs/1903.09121">1903.09121</a></span>. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/2020NatPh..16..907A">2020NatPh..16..907A</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.1038%2Fs41567-020-0914-9">10.1038/s41567-020-0914-9</a></span>. <a href="/wiki/ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/1745-2481">1745-2481</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Nature+Physics&rft.atitle=Evidence+for+quark-matter+cores+in+massive+neutron+stars&rft.volume=16&rft.issue=9&rft.pages=907-910&rft.date=2020-06-01&rft_id=info%3Aarxiv%2F1903.09121&rft.issn=1745-2481&rft_id=info%3Adoi%2F10.1038%2Fs41567-020-0914-9&rft_id=info%3Abibcode%2F2020NatPh..16..907A&rft.aulast=Annala&rft.aufirst=Eemeli&rft.au=Gorda%2C+Tyler&rft.au=Kurkela%2C+Aleksi&rft.au=N%C3%A4ttil%C3%A4%2C+Joonas&rft.au=Vuorinen%2C+Aleksi&rft_id=https%3A%2F%2Fdoi.org%2F10.1038%252Fs41567-020-0914-9&rfr_id=info%3Asid%2Fen.wikipedia.org%3AQCD+matter" class="Z3988"></span></span> </li> <li id="cite_note-8"><span class="mw-cite-backlink"><b><a href="#cite_ref-8">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFBiswas2016" class="citation book cs1 cs1-prop-long-vol">Biswas, Sayan; et al. (2016). <a rel="nofollow" class="external text" href="http://inspirehep.net/record/1483757/references">"A production scenario of Galactic strangelets and an estimation of their possible flux in solar neighborhood"</a>. <i>Proceedings: A production scenario of Galactic strangelets and an estimation of their possible flux in solar neighborhood</i>. Vol. ICRC2015. inSpire. p. 504. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.22323%2F1.236.0504">10.22323/1.236.0504</a></span><span class="reference-accessdate">. Retrieved <span class="nowrap">11 October</span> 2016</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=bookitem&rft.atitle=A+production+scenario+of+Galactic+strangelets+and+an+estimation+of+their+possible+flux+in+solar+neighborhood&rft.btitle=Proceedings%3A+A+production+scenario+of+Galactic+strangelets+and+an+estimation+of+their+possible+flux+in+solar+neighborhood&rft.pages=504&rft.pub=inSpire&rft.date=2016&rft_id=info%3Adoi%2F10.22323%2F1.236.0504&rft.aulast=Biswas&rft.aufirst=Sayan&rft_id=http%3A%2F%2Finspirehep.net%2Frecord%2F1483757%2Freferences&rfr_id=info%3Asid%2Fen.wikipedia.org%3AQCD+matter" class="Z3988"></span></span> </li> <li id="cite_note-9"><span class="mw-cite-backlink"><b><a href="#cite_ref-9">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFMadsen,_Jes2004" class="citation journal cs1">Madsen, Jes (18 November 2004). "Strangelet propagation and cosmic ray flux". <i>Phys. Rev. D</i>. <b>71</b> (1): 014026. <a href="/wiki/ArXiv_(identifier)" class="mw-redirect" title="ArXiv (identifier)">arXiv</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://arxiv.org/abs/astro-ph/0411538">astro-ph/0411538</a></span>. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/2005PhRvD..71a4026M">2005PhRvD..71a4026M</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1103%2FPhysRevD.71.014026">10.1103/PhysRevD.71.014026</a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:119485839">119485839</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Phys.+Rev.+D&rft.atitle=Strangelet+propagation+and+cosmic+ray+flux&rft.volume=71&rft.issue=1&rft.pages=014026&rft.date=2004-11-18&rft_id=info%3Aarxiv%2Fastro-ph%2F0411538&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A119485839%23id-name%3DS2CID&rft_id=info%3Adoi%2F10.1103%2FPhysRevD.71.014026&rft_id=info%3Abibcode%2F2005PhRvD..71a4026M&rft.au=Madsen%2C+Jes&rfr_id=info%3Asid%2Fen.wikipedia.org%3AQCD+matter" class="Z3988"></span></span> </li> <li id="cite_note-10"><span class="mw-cite-backlink"><b><a href="#cite_ref-10">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFHoldomRenZhang2018" class="citation journal cs1">Holdom, Bob; Ren, Jing; Zhang, Chen (31 May 2018). "Quark Matter May Not Be Strange". <i>Physical Review Letters</i>. <b>120</b> (22): 222001. <a href="/wiki/ArXiv_(identifier)" class="mw-redirect" title="ArXiv (identifier)">arXiv</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://arxiv.org/abs/1707.06610">1707.06610</a></span>. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/2018PhRvL.120v2001H">2018PhRvL.120v2001H</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1103%2FPhysRevLett.120.222001">10.1103/PhysRevLett.120.222001</a>. <a href="/wiki/PMID_(identifier)" class="mw-redirect" title="PMID (identifier)">PMID</a> <a rel="nofollow" class="external text" href="https://pubmed.ncbi.nlm.nih.gov/29906186">29906186</a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:49216916">49216916</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Physical+Review+Letters&rft.atitle=Quark+Matter+May+Not+Be+Strange&rft.volume=120&rft.issue=22&rft.pages=222001&rft.date=2018-05-31&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A49216916%23id-name%3DS2CID&rft_id=info%3Abibcode%2F2018PhRvL.120v2001H&rft_id=info%3Aarxiv%2F1707.06610&rft_id=info%3Apmid%2F29906186&rft_id=info%3Adoi%2F10.1103%2FPhysRevLett.120.222001&rft.aulast=Holdom&rft.aufirst=Bob&rft.au=Ren%2C+Jing&rft.au=Zhang%2C+Chen&rfr_id=info%3Asid%2Fen.wikipedia.org%3AQCD+matter" class="Z3988"></span></span> </li> <li id="cite_note-11"><span class="mw-cite-backlink"><b><a href="#cite_ref-11">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://home.cern/about/experiments/alice">"ALICE"</a>. CERN<span class="reference-accessdate">. Retrieved <span class="nowrap">16 December</span> 2015</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=ALICE&rft.pub=CERN&rft_id=http%3A%2F%2Fhome.cern%2Fabout%2Fexperiments%2Falice&rfr_id=info%3Asid%2Fen.wikipedia.org%3AQCD+matter" class="Z3988"></span></span> </li> <li id="cite_note-12"><span class="mw-cite-backlink"><b><a href="#cite_ref-12">^</a></b></span> <span class="reference-text">See <i>"Hunting the quark gluoan plasma"</i> as an example of the research at RHIC.</span> </li> <li id="cite_note-13"><span class="mw-cite-backlink"><b><a href="#cite_ref-13">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFHeinzJacob2000" class="citation arxiv cs1">Heinz, Ulrich; Jacob, Maurice (2000). "Evidence for a New State of Matter: An Assessment of the Results from the CERN Lead Beam Programme". <a href="/wiki/ArXiv_(identifier)" class="mw-redirect" title="ArXiv (identifier)">arXiv</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://arxiv.org/abs/nucl-th/0002042">nucl-th/0002042</a></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=preprint&rft.jtitle=arXiv&rft.atitle=Evidence+for+a+New+State+of+Matter%3A+An+Assessment+of+the+Results+from+the+CERN+Lead+Beam+Programme&rft.date=2000&rft_id=info%3Aarxiv%2Fnucl-th%2F0002042&rft.aulast=Heinz&rft.aufirst=Ulrich&rft.au=Jacob%2C+Maurice&rfr_id=info%3Asid%2Fen.wikipedia.org%3AQCD+matter" class="Z3988"></span></span> </li> <li id="cite_note-14"><span class="mw-cite-backlink"><b><a href="#cite_ref-14">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFHeinzJacob2005" class="citation arxiv cs1">Heinz, Ulrich; Jacob, Maurice (2005). "Quark Matter 2005 – Theoretical Summary". <a href="/wiki/ArXiv_(identifier)" class="mw-redirect" title="ArXiv (identifier)">arXiv</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://arxiv.org/abs/nucl-th/0508062">nucl-th/0508062</a></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=preprint&rft.jtitle=arXiv&rft.atitle=Quark+Matter+2005+%E2%80%93+Theoretical+Summary&rft.date=2005&rft_id=info%3Aarxiv%2Fnucl-th%2F0508062&rft.aulast=Heinz&rft.aufirst=Ulrich&rft.au=Jacob%2C+Maurice&rfr_id=info%3Asid%2Fen.wikipedia.org%3AQCD+matter" class="Z3988"></span></span> </li> <li id="cite_note-RMP-15"><span class="mw-cite-backlink">^ <a href="#cite_ref-RMP_15-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-RMP_15-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-RMP_15-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-RMP_15-3"><sup><i><b>d</b></i></sup></a> <a href="#cite_ref-RMP_15-4"><sup><i><b>e</b></i></sup></a> <a href="#cite_ref-RMP_15-5"><sup><i><b>f</b></i></sup></a> <a href="#cite_ref-RMP_15-6"><sup><i><b>g</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFAlford,_Mark_G.Schmitt,_AndreasRajagopal,_KrishnaSchäfer,_Thomas2008" class="citation journal cs1">Alford, Mark G.; Schmitt, Andreas; Rajagopal, Krishna; Schäfer, Thomas (2008). "Color superconductivity in dense quark matter". <i>Reviews of Modern Physics</i>. <b>80</b> (4): 1455–1515. <a href="/wiki/ArXiv_(identifier)" class="mw-redirect" title="ArXiv (identifier)">arXiv</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://arxiv.org/abs/0709.4635">0709.4635</a></span>. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/2008RvMP...80.1455A">2008RvMP...80.1455A</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1103%2FRevModPhys.80.1455">10.1103/RevModPhys.80.1455</a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:14117263">14117263</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Reviews+of+Modern+Physics&rft.atitle=Color+superconductivity+in+dense+quark+matter&rft.volume=80&rft.issue=4&rft.pages=1455-1515&rft.date=2008&rft_id=info%3Aarxiv%2F0709.4635&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A14117263%23id-name%3DS2CID&rft_id=info%3Adoi%2F10.1103%2FRevModPhys.80.1455&rft_id=info%3Abibcode%2F2008RvMP...80.1455A&rft.au=Alford%2C+Mark+G.&rft.au=Schmitt%2C+Andreas&rft.au=Rajagopal%2C+Krishna&rft.au=Sch%C3%A4fer%2C+Thomas&rfr_id=info%3Asid%2Fen.wikipedia.org%3AQCD+matter" class="Z3988"></span></span> </li> <li id="cite_note-Rischke-16"><span class="mw-cite-backlink">^ <a href="#cite_ref-Rischke_16-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-Rischke_16-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-Rischke_16-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-Rischke_16-3"><sup><i><b>d</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFRischke2004" class="citation journal cs1">Rischke, D (2004). "The quark–gluon plasma in equilibrium". <i>Progress in Particle and Nuclear Physics</i>. <b>52</b> (1): 197–296. <a href="/wiki/ArXiv_(identifier)" class="mw-redirect" title="ArXiv (identifier)">arXiv</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://arxiv.org/abs/nucl-th/0305030">nucl-th/0305030</a></span>. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/2004PrPNP..52..197R">2004PrPNP..52..197R</a>. <a href="/wiki/CiteSeerX_(identifier)" class="mw-redirect" title="CiteSeerX (identifier)">CiteSeerX</a> <span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.265.4175">10.1.1.265.4175</a></span>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1016%2Fj.ppnp.2003.09.002">10.1016/j.ppnp.2003.09.002</a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:119081533">119081533</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Progress+in+Particle+and+Nuclear+Physics&rft.atitle=The+quark%E2%80%93gluon+plasma+in+equilibrium&rft.volume=52&rft.issue=1&rft.pages=197-296&rft.date=2004&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A119081533%23id-name%3DS2CID&rft_id=info%3Abibcode%2F2004PrPNP..52..197R&rft_id=https%3A%2F%2Fciteseerx.ist.psu.edu%2Fviewdoc%2Fsummary%3Fdoi%3D10.1.1.265.4175%23id-name%3DCiteSeerX&rft_id=info%3Adoi%2F10.1016%2Fj.ppnp.2003.09.002&rft_id=info%3Aarxiv%2Fnucl-th%2F0305030&rft.aulast=Rischke&rft.aufirst=D&rfr_id=info%3Asid%2Fen.wikipedia.org%3AQCD+matter" class="Z3988"></span></span> </li> <li id="cite_note-TS-17"><span class="mw-cite-backlink">^ <a href="#cite_ref-TS_17-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-TS_17-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFT._Schäfer2004" class="citation conference cs1">T. Schäfer (2004). "Quark matter". In A. B. Santra (ed.). <i>Mesons and Quarks</i>. 14th National Nuclear Physics Summer School. Alpha Science International. <a href="/wiki/ArXiv_(identifier)" class="mw-redirect" title="ArXiv (identifier)">arXiv</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://arxiv.org/abs/hep-ph/0304281">hep-ph/0304281</a></span>. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/2003hep.ph....4281S">2003hep.ph....4281S</a>. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-81-7319-589-1" title="Special:BookSources/978-81-7319-589-1"><bdi>978-81-7319-589-1</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=conference&rft.atitle=Quark+matter&rft.btitle=Mesons+and+Quarks&rft.pub=Alpha+Science+International&rft.date=2004&rft_id=info%3Aarxiv%2Fhep-ph%2F0304281&rft_id=info%3Abibcode%2F2003hep.ph....4281S&rft.isbn=978-81-7319-589-1&rft.au=T.+Sch%C3%A4fer&rfr_id=info%3Asid%2Fen.wikipedia.org%3AQCD+matter" class="Z3988"></span></span> </li> <li id="cite_note-18"><span class="mw-cite-backlink"><b><a href="#cite_ref-18">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFP._Petreczky2012" class="citation journal cs1">P. Petreczky (2012). "Lattice QCD at non-zero temperature". <i>J. Phys. G</i>. <b>39</b> (9): 093002. <a href="/wiki/ArXiv_(identifier)" class="mw-redirect" title="ArXiv (identifier)">arXiv</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://arxiv.org/abs/1203.5320">1203.5320</a></span>. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/2012JPhG...39i3002P">2012JPhG...39i3002P</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1088%2F0954-3899%2F39%2F9%2F093002">10.1088/0954-3899/39/9/093002</a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:119193093">119193093</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=J.+Phys.+G&rft.atitle=Lattice+QCD+at+non-zero+temperature&rft.volume=39&rft.issue=9&rft.pages=093002&rft.date=2012&rft_id=info%3Aarxiv%2F1203.5320&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A119193093%23id-name%3DS2CID&rft_id=info%3Adoi%2F10.1088%2F0954-3899%2F39%2F9%2F093002&rft_id=info%3Abibcode%2F2012JPhG...39i3002P&rft.au=P.+Petreczky&rfr_id=info%3Asid%2Fen.wikipedia.org%3AQCD+matter" class="Z3988"></span></span> </li> <li id="cite_note-19"><span class="mw-cite-backlink"><b><a href="#cite_ref-19">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFChristian_Schmidt2006" class="citation journal cs1">Christian Schmidt (2006). <a rel="nofollow" class="external text" href="https://doi.org/10.22323%2F1.032.0021">"Lattice QCD at Finite Density"</a>. <i>PoS LAT2006</i>. <b>2006</b> (21): 021. <a href="/wiki/ArXiv_(identifier)" class="mw-redirect" title="ArXiv (identifier)">arXiv</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://arxiv.org/abs/hep-lat/0610116">hep-lat/0610116</a></span>. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/2006slft.confE..21S">2006slft.confE..21S</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://doi.org/10.22323%2F1.032.0021">10.22323/1.032.0021</a></span>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:14890549">14890549</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=PoS+LAT2006&rft.atitle=Lattice+QCD+at+Finite+Density&rft.volume=2006&rft.issue=21&rft.pages=021&rft.date=2006&rft_id=info%3Aarxiv%2Fhep-lat%2F0610116&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A14890549%23id-name%3DS2CID&rft_id=info%3Adoi%2F10.22323%2F1.032.0021&rft_id=info%3Abibcode%2F2006slft.confE..21S&rft.au=Christian+Schmidt&rft_id=https%3A%2F%2Fdoi.org%2F10.22323%252F1.032.0021&rfr_id=info%3Asid%2Fen.wikipedia.org%3AQCD+matter" class="Z3988"></span></span> </li> <li id="cite_note-20"><span class="mw-cite-backlink"><b><a href="#cite_ref-20">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFRajagopal1999" class="citation journal cs1">Rajagopal, K (1999). "Mapping the QCD phase diagram". <i><a href="/wiki/Nuclear_Physics_A" class="mw-redirect" title="Nuclear Physics A">Nuclear Physics A</a></i>. <b>661</b> (1–4): 150–161. <a href="/wiki/ArXiv_(identifier)" class="mw-redirect" title="ArXiv (identifier)">arXiv</a>:<span class="id-lock-free" title="Freely accessible"><a rel="nofollow" class="external text" href="https://arxiv.org/abs/hep-ph/9908360">hep-ph/9908360</a></span>. <a href="/wiki/Bibcode_(identifier)" class="mw-redirect" title="Bibcode (identifier)">Bibcode</a>:<a rel="nofollow" class="external text" href="https://ui.adsabs.harvard.edu/abs/1999NuPhA.661..150R">1999NuPhA.661..150R</a>. <a href="/wiki/Doi_(identifier)" class="mw-redirect" title="Doi (identifier)">doi</a>:<a rel="nofollow" class="external text" href="https://doi.org/10.1016%2FS0375-9474%2899%2985017-9">10.1016/S0375-9474(99)85017-9</a>. <a href="/wiki/S2CID_(identifier)" class="mw-redirect" title="S2CID (identifier)">S2CID</a> <a rel="nofollow" class="external text" href="https://api.semanticscholar.org/CorpusID:15893165">15893165</a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Nuclear+Physics+A&rft.atitle=Mapping+the+QCD+phase+diagram&rft.volume=661&rft.issue=1%E2%80%934&rft.pages=150-161&rft.date=1999&rft_id=info%3Aarxiv%2Fhep-ph%2F9908360&rft_id=https%3A%2F%2Fapi.semanticscholar.org%2FCorpusID%3A15893165%23id-name%3DS2CID&rft_id=info%3Adoi%2F10.1016%2FS0375-9474%2899%2985017-9&rft_id=info%3Abibcode%2F1999NuPhA.661..150R&rft.aulast=Rajagopal&rft.aufirst=K&rfr_id=info%3Asid%2Fen.wikipedia.org%3AQCD+matter" class="Z3988"></span></span> </li> <li id="cite_note-21"><span class="mw-cite-backlink"><b><a href="#cite_ref-21">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.sciencedaily.com/releases/2020/06/200601120036.htm">"A new type of matter discovered inside neutron stars"</a>. <i>ScienceDaily</i><span class="reference-accessdate">. Retrieved <span class="nowrap">2020-06-01</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=ScienceDaily&rft.atitle=A+new+type+of+matter+discovered+inside+neutron+stars&rft_id=https%3A%2F%2Fwww.sciencedaily.com%2Freleases%2F2020%2F06%2F200601120036.htm&rfr_id=info%3Asid%2Fen.wikipedia.org%3AQCD+matter" class="Z3988"></span></span> </li> </ol></div> <div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=QCD_matter&action=edit&section=19" title="Edit section: External links"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a rel="nofollow" class="external text" href="http://qgp.phy.duke.edu/">Virtual Journal on QCD Matter</a></li> <li><a rel="nofollow" class="external text" href="http://www.bnl.gov/rhic/news2/news.asp?a=1075&t=pr">RHIC finds Exotic Antimatter</a></li></ul> <div class="navbox-styles"><style data-mw-deduplicate="TemplateStyles:r1129693374">.mw-parser-output .hlist dl,.mw-parser-output .hlist ol,.mw-parser-output .hlist ul{margin:0;padding:0}.mw-parser-output .hlist dd,.mw-parser-output .hlist dt,.mw-parser-output .hlist li{margin:0;display:inline}.mw-parser-output .hlist.inline,.mw-parser-output .hlist.inline dl,.mw-parser-output .hlist.inline ol,.mw-parser-output .hlist.inline ul,.mw-parser-output .hlist dl dl,.mw-parser-output .hlist dl ol,.mw-parser-output .hlist dl ul,.mw-parser-output .hlist ol dl,.mw-parser-output .hlist ol ol,.mw-parser-output .hlist ol ul,.mw-parser-output .hlist ul dl,.mw-parser-output .hlist ul ol,.mw-parser-output .hlist ul ul{display:inline}.mw-parser-output .hlist .mw-empty-li{display:none}.mw-parser-output .hlist dt::after{content:": "}.mw-parser-output .hlist dd::after,.mw-parser-output .hlist li::after{content:" · ";font-weight:bold}.mw-parser-output .hlist dd:last-child::after,.mw-parser-output .hlist dt:last-child::after,.mw-parser-output .hlist li:last-child::after{content:none}.mw-parser-output .hlist dd dd:first-child::before,.mw-parser-output .hlist dd dt:first-child::before,.mw-parser-output .hlist dd li:first-child::before,.mw-parser-output .hlist dt dd:first-child::before,.mw-parser-output .hlist dt dt:first-child::before,.mw-parser-output .hlist dt li:first-child::before,.mw-parser-output .hlist li dd:first-child::before,.mw-parser-output .hlist li dt:first-child::before,.mw-parser-output .hlist li li:first-child::before{content:" (";font-weight:normal}.mw-parser-output .hlist dd dd:last-child::after,.mw-parser-output .hlist dd dt:last-child::after,.mw-parser-output .hlist dd li:last-child::after,.mw-parser-output .hlist dt dd:last-child::after,.mw-parser-output .hlist dt dt:last-child::after,.mw-parser-output .hlist dt li:last-child::after,.mw-parser-output .hlist li dd:last-child::after,.mw-parser-output .hlist li dt:last-child::after,.mw-parser-output .hlist li li:last-child::after{content:")";font-weight:normal}.mw-parser-output .hlist ol{counter-reset:listitem}.mw-parser-output .hlist ol>li{counter-increment:listitem}.mw-parser-output .hlist ol>li::before{content:" "counter(listitem)"\a0 "}.mw-parser-output .hlist dd ol>li:first-child::before,.mw-parser-output .hlist dt ol>li:first-child::before,.mw-parser-output .hlist li ol>li:first-child::before{content:" ("counter(listitem)"\a0 "}</style><style data-mw-deduplicate="TemplateStyles:r1236075235">.mw-parser-output .navbox{box-sizing:border-box;border:1px solid #a2a9b1;width:100%;clear:both;font-size:88%;text-align:center;padding:1px;margin:1em auto 0}.mw-parser-output .navbox .navbox{margin-top:0}.mw-parser-output .navbox+.navbox,.mw-parser-output .navbox+.navbox-styles+.navbox{margin-top:-1px}.mw-parser-output .navbox-inner,.mw-parser-output .navbox-subgroup{width:100%}.mw-parser-output .navbox-group,.mw-parser-output .navbox-title,.mw-parser-output .navbox-abovebelow{padding:0.25em 1em;line-height:1.5em;text-align:center}.mw-parser-output .navbox-group{white-space:nowrap;text-align:right}.mw-parser-output .navbox,.mw-parser-output .navbox-subgroup{background-color:#fdfdfd}.mw-parser-output .navbox-list{line-height:1.5em;border-color:#fdfdfd}.mw-parser-output .navbox-list-with-group{text-align:left;border-left-width:2px;border-left-style:solid}.mw-parser-output tr+tr>.navbox-abovebelow,.mw-parser-output tr+tr>.navbox-group,.mw-parser-output tr+tr>.navbox-image,.mw-parser-output tr+tr>.navbox-list{border-top:2px solid #fdfdfd}.mw-parser-output .navbox-title{background-color:#ccf}.mw-parser-output .navbox-abovebelow,.mw-parser-output .navbox-group,.mw-parser-output .navbox-subgroup .navbox-title{background-color:#ddf}.mw-parser-output .navbox-subgroup .navbox-group,.mw-parser-output .navbox-subgroup .navbox-abovebelow{background-color:#e6e6ff}.mw-parser-output .navbox-even{background-color:#f7f7f7}.mw-parser-output .navbox-odd{background-color:transparent}.mw-parser-output .navbox .hlist td dl,.mw-parser-output .navbox .hlist td ol,.mw-parser-output .navbox .hlist td ul,.mw-parser-output .navbox td.hlist dl,.mw-parser-output .navbox td.hlist ol,.mw-parser-output .navbox td.hlist ul{padding:0.125em 0}.mw-parser-output .navbox .navbar{display:block;font-size:100%}.mw-parser-output .navbox-title .navbar{float:left;text-align:left;margin-right:0.5em}body.skin--responsive .mw-parser-output .navbox-image img{max-width:none!important}@media print{body.ns-0 .mw-parser-output .navbox{display:none!important}}</style></div><div role="navigation" class="navbox" aria-labelledby="States_of_matter_(list)" style="padding:3px"><table class="nowraplinks hlist mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="3"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><style data-mw-deduplicate="TemplateStyles:r1239400231">.mw-parser-output .navbar{display:inline;font-size:88%;font-weight:normal}.mw-parser-output .navbar-collapse{float:left;text-align:left}.mw-parser-output .navbar-boxtext{word-spacing:0}.mw-parser-output .navbar ul{display:inline-block;white-space:nowrap;line-height:inherit}.mw-parser-output .navbar-brackets::before{margin-right:-0.125em;content:"[ "}.mw-parser-output .navbar-brackets::after{margin-left:-0.125em;content:" ]"}.mw-parser-output .navbar li{word-spacing:-0.125em}.mw-parser-output .navbar a>span,.mw-parser-output .navbar a>abbr{text-decoration:inherit}.mw-parser-output .navbar-mini abbr{font-variant:small-caps;border-bottom:none;text-decoration:none;cursor:inherit}.mw-parser-output .navbar-ct-full{font-size:114%;margin:0 7em}.mw-parser-output .navbar-ct-mini{font-size:114%;margin:0 4em}html.skin-theme-clientpref-night .mw-parser-output .navbar li a abbr{color:var(--color-base)!important}@media(prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .navbar li a abbr{color:var(--color-base)!important}}@media print{.mw-parser-output .navbar{display:none!important}}</style><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:States_of_matter" title="Template:States of matter"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:States_of_matter" title="Template talk:States of matter"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:States_of_matter" title="Special:EditPage/Template:States of matter"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="States_of_matter_(list)" style="font-size:114%;margin:0 4em"><a href="/wiki/State_of_matter" title="State of matter">States of matter</a> (<a href="/wiki/List_of_states_of_matter" title="List of states of matter">list</a>)</div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%">State</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Solid" title="Solid">Solid</a></li> <li><a href="/wiki/Liquid" title="Liquid">Liquid</a></li> <li><a href="/wiki/Gas" title="Gas">Gas</a> / <a href="/wiki/Vapor" title="Vapor">Vapor</a></li> <li><a href="/wiki/Supercritical_fluid" title="Supercritical fluid">Supercritical fluid</a></li> <li><a href="/wiki/Plasma_(physics)" title="Plasma (physics)">Plasma</a></li></ul> </div></td><td class="noviewer navbox-image" rowspan="7" style="width:1px;padding:0 0 0 2px"><div><span typeof="mw:File"><a href="/wiki/File:Phase_change_-_en.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/0/0b/Phase_change_-_en.svg/150px-Phase_change_-_en.svg.png" decoding="async" width="150" height="159" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/0/0b/Phase_change_-_en.svg/225px-Phase_change_-_en.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/0/0b/Phase_change_-_en.svg/300px-Phase_change_-_en.svg.png 2x" data-file-width="493" data-file-height="524" /></a></span></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Low energy</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Bose%E2%80%93Einstein_condensate" title="Bose–Einstein condensate">Bose–Einstein condensate</a></li> <li><a href="/wiki/Fermionic_condensate" title="Fermionic condensate">Fermionic condensate</a></li> <li><a href="/wiki/Degenerate_matter" title="Degenerate matter">Degenerate matter</a></li> <li><a href="/wiki/Quantum_Hall_effect" title="Quantum Hall effect">Quantum Hall</a></li> <li><a href="/wiki/Rydberg_matter" title="Rydberg matter">Rydberg matter</a></li> <li><a href="/wiki/Strange_matter" title="Strange matter">Strange matter</a></li> <li><a href="/wiki/Superfluidity" title="Superfluidity">Superfluid</a></li> <li><a href="/wiki/Supersolid" title="Supersolid">Supersolid</a></li> <li><a href="/wiki/Photonic_molecule" title="Photonic molecule">Photonic molecule</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">High energy</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a class="mw-selflink selflink">QCD matter</a></li> <li><a href="/wiki/Quark%E2%80%93gluon_plasma" title="Quark–gluon plasma">Quark–gluon plasma</a></li> <li><a href="/wiki/Color-glass_condensate" title="Color-glass condensate">Color-glass condensate</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Other states</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Colloid" title="Colloid">Colloid</a></li> <li><a href="/wiki/Crystal" title="Crystal">Crystal</a></li> <li><a href="/wiki/Liquid_crystal" title="Liquid crystal">Liquid crystal</a></li> <li><a href="/wiki/Time_crystal" title="Time crystal">Time crystal</a></li> <li><a href="/wiki/Quantum_spin_liquid" title="Quantum spin liquid">Quantum spin liquid</a></li> <li><a href="/wiki/Exotic_matter" title="Exotic matter">Exotic matter</a></li> <li><a href="/wiki/Programmable_matter" title="Programmable matter">Programmable matter</a></li> <li><a href="/wiki/Dark_matter" title="Dark matter">Dark matter</a></li> <li><a href="/wiki/Antimatter" title="Antimatter">Antimatter</a></li> <li>Magnetically ordered <ul><li><a href="/wiki/Antiferromagnetism" title="Antiferromagnetism">Antiferromagnet</a></li> <li><a href="/wiki/Ferrimagnetism" title="Ferrimagnetism">Ferrimagnet</a></li> <li><a href="/wiki/Ferromagnetism" title="Ferromagnetism">Ferromagnet</a></li></ul></li> <li><a href="/wiki/String-net_liquid" title="String-net liquid">String-net liquid</a></li> <li><a href="/wiki/Superglass" title="Superglass">Superglass</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Phase_transitions" class="mw-redirect" title="Phase transitions">Phase transitions</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Boiling" title="Boiling">Boiling</a></li> <li><a href="/wiki/Boiling_point" title="Boiling point">Boiling point</a></li> <li><a href="/wiki/Condensation" title="Condensation">Condensation</a></li> <li><a href="/wiki/Critical_line_(thermodynamics)" title="Critical line (thermodynamics)">Critical line</a></li> <li><a href="/wiki/Critical_point_(thermodynamics)" title="Critical point (thermodynamics)">Critical point</a></li> <li><a href="/wiki/Crystallization" title="Crystallization">Crystallization</a></li> <li><a href="/wiki/Deposition_(phase_transition)" title="Deposition (phase transition)">Deposition</a></li> <li><a href="/wiki/Evaporation" title="Evaporation">Evaporation</a></li> <li><a href="/wiki/Flash_evaporation" title="Flash evaporation">Flash evaporation</a></li> <li><a href="/wiki/Freezing" title="Freezing">Freezing</a></li> <li><a href="/wiki/Chemical_ionization" title="Chemical ionization">Chemical ionization</a></li> <li><a href="/wiki/Ionization" title="Ionization">Ionization</a></li> <li><a href="/wiki/Lambda_point" title="Lambda point">Lambda point</a></li> <li><a href="/wiki/Melting" title="Melting">Melting</a></li> <li><a href="/wiki/Melting_point" title="Melting point">Melting point</a></li> <li><a href="/wiki/Plasma_recombination" title="Plasma recombination">Recombination</a></li> <li><a href="/wiki/Regelation" title="Regelation">Regelation</a></li> <li><a href="/wiki/Vapor%E2%80%93liquid_equilibrium" title="Vapor–liquid equilibrium">Saturated fluid</a></li> <li><a href="/wiki/Sublimation_(phase_transition)" title="Sublimation (phase transition)">Sublimation</a></li> <li><a href="/wiki/Supercooling" title="Supercooling">Supercooling</a></li> <li><a href="/wiki/Triple_point" title="Triple point">Triple point</a></li> <li><a href="/wiki/Vaporization" title="Vaporization">Vaporization</a></li> <li><a href="/wiki/Vitrification" title="Vitrification">Vitrification</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Quantities</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Enthalpy_of_fusion" title="Enthalpy of fusion">Enthalpy of fusion</a></li> <li><a href="/wiki/Enthalpy_of_sublimation" title="Enthalpy of sublimation">Enthalpy of sublimation</a></li> <li><a href="/wiki/Enthalpy_of_vaporization" title="Enthalpy of vaporization">Enthalpy of vaporization</a></li> <li><a href="/wiki/Latent_heat" title="Latent heat">Latent heat</a></li> <li><a href="/wiki/Latent_internal_energy" title="Latent internal energy">Latent internal energy</a></li> <li><a href="/wiki/Trouton%27s_rule" title="Trouton's rule">Trouton's rule</a></li> <li><a href="/wiki/Volatility_(chemistry)" title="Volatility (chemistry)">Volatility</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Concepts</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Baryonic_matter" class="mw-redirect" title="Baryonic matter">Baryonic matter</a></li> <li><a href="/wiki/Binodal" title="Binodal">Binodal</a></li> <li><a href="/wiki/Compressed_fluid" title="Compressed fluid">Compressed fluid</a></li> <li><a href="/wiki/Cooling_curve" title="Cooling curve">Cooling curve</a></li> <li><a href="/wiki/Equation_of_state" title="Equation of state">Equation of state</a></li> <li><a href="/wiki/Leidenfrost_effect" title="Leidenfrost effect">Leidenfrost effect</a></li> <li><a href="/wiki/Macroscopic_quantum_phenomena" title="Macroscopic quantum phenomena">Macroscopic quantum phenomena</a></li> <li><a href="/wiki/Mpemba_effect" title="Mpemba effect">Mpemba effect</a></li> <li><a href="/wiki/Order_and_disorder_(physics)" class="mw-redirect" title="Order and disorder (physics)">Order and disorder (physics)</a></li> <li><a href="/wiki/Spinodal" title="Spinodal">Spinodal</a></li> <li><a href="/wiki/Superconductivity" title="Superconductivity">Superconductivity</a></li> <li><a href="/wiki/Superheated_water" title="Superheated water">Superheated vapor</a></li> <li><a href="/wiki/Superheating" title="Superheating">Superheating</a></li> <li><a href="/wiki/Thermo-dielectric_effect" title="Thermo-dielectric effect">Thermo-dielectric effect</a></li></ul> </div></td></tr></tbody></table></div>    </div><noscript><img src="https://login.wikimedia.org/wiki/Special:CentralAutoLogin/start?type=1x1" alt="" width="1" height="1" style="border: none; position: absolute;"></noscript> <div class="printfooter" data-nosnippet="">Retrieved from "<a dir="ltr" href="https://en.wikipedia.org/w/index.php?title=QCD_matter&oldid=1216611248">https://en.wikipedia.org/w/index.php?title=QCD_matter&oldid=1216611248</a>"</div></div> <div id="catlinks" class="catlinks" data-mw="interface"><div id="mw-normal-catlinks" class="mw-normal-catlinks"><a href="/wiki/Help:Category" title="Help:Category">Categories</a>: <ul><li><a href="/wiki/Category:Quark_matter" title="Category:Quark matter">Quark matter</a></li><li><a href="/wiki/Category:Quantum_chromodynamics" title="Category:Quantum chromodynamics">Quantum chromodynamics</a></li><li><a href="/wiki/Category:Phases_of_matter" title="Category:Phases of matter">Phases of matter</a></li><li><a href="/wiki/Category:Unsolved_problems_in_physics" title="Category:Unsolved problems in physics">Unsolved problems in physics</a></li></ul></div><div id="mw-hidden-catlinks" class="mw-hidden-catlinks mw-hidden-cats-hidden">Hidden categories: <ul><li><a href="/wiki/Category:CS1:_long_volume_value" title="Category:CS1: long volume value">CS1: long volume value</a></li><li><a href="/wiki/Category:Articles_with_short_description" title="Category:Articles with short description">Articles with short description</a></li><li><a href="/wiki/Category:Short_description_is_different_from_Wikidata" title="Category:Short description is different from Wikidata">Short description is different from Wikidata</a></li><li><a href="/wiki/Category:Pages_displaying_short_descriptions_of_redirect_targets_via_Module:Annotated_link" title="Category:Pages displaying short descriptions of redirect targets via Module:Annotated link">Pages displaying short descriptions of redirect targets via Module:Annotated link</a></li></ul></div></div> </div> </main> </div> <div class="mw-footer-container"> <footer id="footer" class="mw-footer" > <ul id="footer-info"> <li id="footer-info-lastmod"> This page was last edited on 1 April 2024, at 01:14<span class="anonymous-show"> (UTC)</span>.</li> <li id="footer-info-copyright">Text is available under the <a href="/wiki/Wikipedia:Text_of_the_Creative_Commons_Attribution-ShareAlike_4.0_International_License" title="Wikipedia:Text of the Creative Commons Attribution-ShareAlike 4.0 International License">Creative Commons Attribution-ShareAlike 4.0 License</a>; additional terms may apply. By using this site, you agree to the <a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Terms_of_Use" class="extiw" title="foundation:Special:MyLanguage/Policy:Terms of Use">Terms of Use</a> and <a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Privacy_policy" class="extiw" title="foundation:Special:MyLanguage/Policy:Privacy policy">Privacy Policy</a>. Wikipedia® is a registered trademark of the <a rel="nofollow" class="external text" href="https://wikimediafoundation.org/">Wikimedia Foundation, Inc.</a>, a non-profit organization.</li> </ul> <ul id="footer-places"> <li id="footer-places-privacy"><a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Privacy_policy">Privacy policy</a></li> <li id="footer-places-about"><a href="/wiki/Wikipedia:About">About Wikipedia</a></li> <li id="footer-places-disclaimers"><a href="/wiki/Wikipedia:General_disclaimer">Disclaimers</a></li> <li id="footer-places-contact"><a href="//en.wikipedia.org/wiki/Wikipedia:Contact_us">Contact Wikipedia</a></li> <li id="footer-places-wm-codeofconduct"><a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Universal_Code_of_Conduct">Code of Conduct</a></li> <li id="footer-places-developers"><a href="https://developer.wikimedia.org">Developers</a></li> <li id="footer-places-statslink"><a href="https://stats.wikimedia.org/#/en.wikipedia.org">Statistics</a></li> <li id="footer-places-cookiestatement"><a href="https://foundation.wikimedia.org/wiki/Special:MyLanguage/Policy:Cookie_statement">Cookie statement</a></li> <li id="footer-places-mobileview"><a href="//en.m.wikipedia.org/w/index.php?title=QCD_matter&mobileaction=toggle_view_mobile" class="noprint stopMobileRedirectToggle">Mobile view</a></li> </ul> <ul id="footer-icons" class="noprint"> <li id="footer-copyrightico"><a href="https://wikimediafoundation.org/" class="cdx-button cdx-button--fake-button cdx-button--size-large cdx-button--fake-button--enabled"><img src="/static/images/footer/wikimedia-button.svg" width="84" height="29" alt="Wikimedia Foundation" loading="lazy"></a></li> <li id="footer-poweredbyico"><a href="https://www.mediawiki.org/" class="cdx-button cdx-button--fake-button cdx-button--size-large cdx-button--fake-button--enabled"><img src="/w/resources/assets/poweredby_mediawiki.svg" alt="Powered by MediaWiki" width="88" height="31" loading="lazy"></a></li> </ul> </footer> </div> </div> </div> <div class="vector-settings" id="p-dock-bottom"> <ul></ul> </div><script>(RLQ=window.RLQ||[]).push(function(){mw.config.set({"wgHostname":"mw-web.codfw.main-cc877b49b-hsx6b","wgBackendResponseTime":204,"wgPageParseReport":{"limitreport":{"cputime":"0.542","walltime":"0.655","ppvisitednodes":{"value":2857,"limit":1000000},"postexpandincludesize":{"value":61859,"limit":2097152},"templateargumentsize":{"value":1123,"limit":2097152},"expansiondepth":{"value":8,"limit":100},"expensivefunctioncount":{"value":2,"limit":500},"unstrip-depth":{"value":1,"limit":20},"unstrip-size":{"value":85467,"limit":5000000},"entityaccesscount":{"value":0,"limit":400},"timingprofile":["100.00% 579.420 1 -total"," 29.39% 170.264 9 Template:Annotated_link"," 23.10% 133.836 10 Template:Cite_journal"," 20.94% 121.317 1 Template:Reflist"," 14.28% 82.763 1 Template:States_of_matter"," 13.73% 79.557 1 Template:Navbox"," 11.70% 67.784 1 Template:Short_description"," 7.24% 41.955 2 Template:Pagetype"," 3.01% 17.469 5 Template:Cite_web"," 3.01% 17.441 1 Template:Main"]},"scribunto":{"limitreport-timeusage":{"value":"0.365","limit":"10.000"},"limitreport-memusage":{"value":13372190,"limit":52428800}},"cachereport":{"origin":"mw-web.codfw.main-f7b5ccf54-lgq79","timestamp":"20241125153812","ttl":2592000,"transientcontent":false}}});});</script> <script type="application/ld+json">{"@context":"https:\/\/schema.org","@type":"Article","name":"QCD matter","url":"https:\/\/en.wikipedia.org\/wiki\/QCD_matter","sameAs":"http:\/\/www.wikidata.org\/entity\/Q2755153","mainEntity":"http:\/\/www.wikidata.org\/entity\/Q2755153","author":{"@type":"Organization","name":"Contributors to Wikimedia projects"},"publisher":{"@type":"Organization","name":"Wikimedia Foundation, Inc.","logo":{"@type":"ImageObject","url":"https:\/\/www.wikimedia.org\/static\/images\/wmf-hor-googpub.png"}},"datePublished":"2005-05-21T09:52:59Z","dateModified":"2024-04-01T01:14:58Z","headline":"number of theorized phases of matter whose degrees of freedom include quarks and gluons"}</script> </body> </html>