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Title: Machine learning a fixed point action for SU(3) gauge theory with a gauge equivariant convolutional neural network

Fixed point lattice actions are designed to have continuum classical properties unaffected by discretization effects and reduced lattice artifacts at the quantum level. They provide a possible way to extract continuum physics with coarser lattices, thereby allowing one to circumvent problems with critical slowing down and topological freezing toward the continuum limit. A crucial ingredient for practical applications is to find an accurate and compact parametrization of a fixed point action, since many of its properties are only implicitly defined. Here we use machine learning methods to revisit the question of how to parametrize fixed point actions. In particular, we obtain a fixed point action for four-dimensional SU(3) gauge theory using convolutional neural networks with exact gauge invariance. The large operator space allows us to find superior parametrizations compared to previous studies, a necessary first step for future Monte Carlo simulations and scaling studies.

<supplementary-material><permissions><copyright-statement>Published by the American Physical Society</copyright-statement><copyright-year>2024</copyright-year></permissions></supplementary-material></sec> </span> <a href='#' class='show open-abstract' style='margin-left:10px;'>more »</a> <a href='#' class='hide close-abstract' style='margin-left:10px;'>« less</a> <div style="clear:both;margin-bottom:20px;"></div> <dl class="dl-horizontal small semi-colon-delimited-data"> <dt>Award ID(s):</dt> <dd> <span> <a target="_blank" rel="noopener noreferrer" href="https://par.nsf.gov/search/award_ids:2014150"> 2014150</a> </span> </dd> </dl> <dl class="dl-horizontal small"> <dt>PAR ID:</dt> <dd>10546359</dd> </dl> <dl class="dl-horizontal small"> <dt>Author(s) / Creator(s):</dt> <dd> <a target="_blank" rel="noopener noreferrer" href="https://par.nsf.gov/search/author:"Holland, Kieran""><span class="author" itemprop="author">Holland, Kieran</span></a><span class="sep">; </span><a target="_blank" rel="noopener noreferrer" href="https://par.nsf.gov/search/author:"Ipp, Andreas""><span class="author" itemprop="author">Ipp, Andreas</span></a><span class="sep">; </span><a target="_blank" rel="noopener noreferrer" href="https://par.nsf.gov/search/author:"Müller, David I""><span class="author" itemprop="author">Müller, David I</span></a><span class="sep">; </span><a target="_blank" rel="noopener noreferrer" href="https://par.nsf.gov/search/author:"Wenger, Urs""><span class="author" itemprop="author">Wenger, Urs</span></a></dd> </dl> <dl class="dl-horizontal small"> <dt>Publisher / Repository:</dt> <dd itemprop="publisher">American Physical Society</dd> </dl> <dl class="dl-horizontal small"> <dt>Date Published:</dt> <dd> <time itemprop="datePublished" datetime="2024-10-01">2024-10-01</time> </dd> </dl> <dl class="dl-horizontal small"> <dt>Journal Name:</dt> <dd>Physical Review D</dd> </dl> <dl class="dl-horizontal small"> <dt>Volume:</dt> <dd>110</dd> </dl> <dl class="dl-horizontal small"> <dt>Issue:</dt> <dd>7</dd> </dl> <dl class="dl-horizontal small"> <dt>ISSN:</dt> <dd>2470-0010</dd> </dl> <dl class="dl-horizontal small"> <dt>Format(s):</dt> <dd>Medium: X</dd> </dl> <dl class="dl-horizontal small semi-colon-delimited-data"> <dt>Sponsoring Org:</dt> <dd itemprop="sourceOrganization"> <span>National Science Foundation</span> </dd> </dl> <div class="clearfix"></div> </div> </div> <div id="citation-addl" class="hidden-print"> <h5 id='mlt-header'>More Like this</h5> <ol class="item-list documents" id="citation-mlt" style="min-height: 80px;"> <li> <div class="article item document" itemscope itemtype="http://schema.org/TechArticle"> <div class="item-info"> <div class="title"> <a href="https://par.nsf.gov/biblio/10556983-new-basis-hamiltonian-su-simulations" itemprop="url"> <span class='span-link' itemprop="name">New basis for Hamiltonian SU(2) simulations</span> </a> </div> <div> <strong> <a class="misc external-link" href="https://doi.org/10.1103/PhysRevD.109.074501" target="_blank" title="Link to document DOI">https://doi.org/10.1103/PhysRevD.109.074501  <span class="fas fa-external-link-alt"></span></a> </strong> </div> <div class="metadata"> <span class="authors"> <span class="author" itemprop="author">D’Andrea, Irian</span> <span class="sep">; </span><span class="author" itemprop="author">Bauer, Christian W</span> <span class="sep">; </span><span class="author" itemprop="author">Grabowska, Dorota M</span> <span class="sep">; </span><span class="author" itemprop="author">Freytsis, Marat</span> </span> <span class="year">( <time itemprop="datePublished" datetime="2024-04-01">April 2024</time> , Physical Review D) </span> </div> <div style="cursor: pointer;-webkit-line-clamp: 5;" class="abstract" itemprop="description"> <p>Due to rapidly improving quantum computing hardware, Hamiltonian simulations of relativistic lattice field theories have seen a resurgence of attention. 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Little prior knowledge is assumed, so this may also be used as an introduction to the subject of Hamiltonian formulations of lattice gauge theories.</p> <sec><supplementary-material><permissions><copyright-statement>Published by the American Physical Society</copyright-statement><copyright-year>2024</copyright-year></permissions></supplementary-material></sec> </div> <a href='#' class='show open-abstract' style='margin-left:10px;'>more »</a> <a href='#' class='hide close-abstract' style='margin-left:10px;'>« less</a> </div><div class="clearfix"></div> </div> </li> <li> <div class="article item document" itemscope itemtype="http://schema.org/TechArticle"> <div class="item-info"> <div class="title"> <a href="https://par.nsf.gov/biblio/10521342-deconfined-quantum-criticality-nodal-wave-superconductivity-neel-order-charge-order-square-lattice-half-filling" itemprop="url"> <span class='span-link' itemprop="name">Deconfined quantum criticality of nodal d -wave superconductivity, Néel order, and charge order on the square lattice at half-filling</span> </a> </div> <div> <strong> <a class="misc external-link" href="https://doi.org/10.1103/PhysRevResearch.6.033018" target="_blank" title="Link to document DOI">https://doi.org/10.1103/PhysRevResearch.6.033018  <span class="fas fa-external-link-alt"></span></a> </strong> </div> <div class="metadata"> <span class="authors"> <span class="author" itemprop="author">Christos, Maine</span> <span class="sep">; </span><span class="author" itemprop="author">Shackleton, Henry</span> <span class="sep">; </span><span class="author" itemprop="author">Sachdev, Subir</span> <span class="sep">; </span><span class="author" itemprop="author">Luo, Zhu-Xi</span> </span> <span class="year">( <time itemprop="datePublished" datetime="2024-07-01">July 2024</time> , Physical Review Research) </span> </div> <div style="cursor: pointer;-webkit-line-clamp: 5;" class="abstract" itemprop="description"> <p>We consider a SU(2) lattice gauge theory on the square lattice, with a single fundamental complex fermion and a single fundamental complex boson on each lattice site. 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We provide a forward-looking introduction to RIXS and outline how this technique is poised to deepen our insight into the nature of quantum materials and of their emergent electronic phenomena.</p> <sec><supplementary-material><permissions><copyright-statement>Published by the American Physical Society</copyright-statement><copyright-year>2024</copyright-year></permissions></supplementary-material></sec> </div> <a href='#' class='show open-abstract' style='margin-left:10px;'>more »</a> <a href='#' class='hide close-abstract' style='margin-left:10px;'>« less</a> </div><div class="clearfix"></div> </div> </li> <li> <div class="article item document" itemscope itemtype="http://schema.org/TechArticle"> <div class="item-info"> <div class="title"> <a href="https://par.nsf.gov/biblio/10515604-matrix-product-study-spin-fractionalization-one-dimensional-kondo-insulator" itemprop="url"> <span class='span-link' itemprop="name">Matrix product study of spin fractionalization in the one-dimensional Kondo insulator</span> </a> </div> <div> <strong> <a class="misc external-link" href="https://doi.org/10.1103/PhysRevResearch.6.023227" target="_blank" title="Link to document DOI">https://doi.org/10.1103/PhysRevResearch.6.023227  <span class="fas fa-external-link-alt"></span></a> </strong> </div> <div class="metadata"> <span class="authors"> <span class="author" itemprop="author">Chen, Jing</span> <span class="sep">; </span><span class="author" itemprop="author">Stoudenmire, E Miles</span> <span class="sep">; </span><span class="author" itemprop="author">Komijani, Yashar</span> <span class="sep">; </span><span class="author" itemprop="author">Coleman, Piers</span> </span> <span class="year">( <time itemprop="datePublished" datetime="2024-06-01">June 2024</time> , Physical Review Research) </span> </div> <div style="cursor: pointer;-webkit-line-clamp: 5;" class="abstract" itemprop="description"> <p>The Kondo lattice is one of the classic examples of strongly correlated electronic systems. 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Furthermore, spin excitations can be thought to be composed of such fractionalized quasiparticles with a residual interaction which tend to disappear at weak Kondo coupling.</p> <sec><supplementary-material><permissions><copyright-statement>Published by the American Physical Society</copyright-statement><copyright-year>2024</copyright-year></permissions></supplementary-material></sec> </div> <a href='#' class='show open-abstract' style='margin-left:10px;'>more »</a> <a href='#' class='hide close-abstract' style='margin-left:10px;'>« less</a> </div><div class="clearfix"></div> </div> </li> </ol> <div class="push_top"></div> </div> </div> <div class="col-md-3"> <div id="citation-sidebar"> <ul class="nav nav-list" id="citation-fulltext-sidebar" style="font-size: 14px; font-family: Georgia Regular;"> <li style="font-weight: bold; margin-bottom: 5px; font-size:13px;">Free Publicly Accessible Full Text</li> <li class="small"> This content will become publicly available on October 1, 2025</li> <li class="divider"></li> <li style="font-weight: bold;font-size:13px;">Journal Article:</li> <li style="word-break:break-all" class="small"> <a href="https://doi.org/10.1103/PhysRevD.110.074502" target="_blank" rel="noopener noreferrer" title="Document DOI URL" class="external-link" data-ostiid="10546359" style="word-wrap: break-word;">https://doi.org/10.1103/PhysRevD.110.074502  <span class="fas fa-external-link-alt"></span></a></li> </ul> <div class="hidden-print"> <ul class="nav nav-list clearfix" id="sidebar-feedback" style="margin-top: 20px; margin-bottom: 20px; clear: both;"> <li style="position: relative;"> <div class="feedback-container"> <div style="font-family: Georgia Regular; font-size: 14px; color: #313b52; padding:20px;"> Have feedback or suggestions for a way to improve these results?<br/> <span style="text-decoration: underline;"> <script type="text/javascript" defer>/* <![CDATA[ */ user = "feedback"; site = "research.gov"; subject = "?subject=Comments or Suggestions"; content = "<span class='fa fa-envelope'></span><span class='span-link' style='padding-left:5px'>Let us know</span>"; id = ""; document.write('<a itemprop="'+ id +'" href="mailto:' + user + '@' + site + subject + '">' + (content != '' ? content : (user + '@' + site)) + '</a>'); /* ]]> */</script> <noscript></noscript>!</span> </div> </li> </ul> <ul class="nav nav-list" style="font-size: 14px; font-family: Arial Regular;"> <li class="nav-header header-format">Citation Formats</li> <li class="links-format"><a href="#cite-mla" data-toggle="modal">MLA</a> <div id="cite-mla" class="modal" tabindex="-1" role="dialog" aria-labelledby="cite-mla_label" aria-hidden="true"> <div class="modal-dialog"> <div class="modal-content"> <div class="modal-header"> <button type="button" class="close" data-dismiss="modal" aria-hidden="true">×</button> <strong id="cite-mla_label">Cite: MLA Format</strong> </div> <div class="modal-body" >Holland, Kieran, Ipp, Andreas, Müller, David I, and Wenger, Urs. <em>Machine learning a fixed point action for SU(3) gauge theory with a gauge equivariant convolutional neural network</em>. Retrieved from https://par.nsf.gov/biblio/10546359. <em>Physical Review D</em> 110.7 Web. doi:10.1103/PhysRevD.110.074502. </div> <div class="modal-footer"> <button class="btn btn-sm btn-default" data-dismiss="modal" aria-hidden="true">Close</button> </div> </div> </div> </div></li> <li class="links-format"><a href="#cite-apa" data-toggle="modal">APA</a> <div id="cite-apa" class="modal" tabindex="-1" role="dialog" aria-labelledby="cite-apa_label" aria-hidden="true"> <div class="modal-dialog"> <div class="modal-content"> <div class="modal-header"> <button type="button" class="close" data-dismiss="modal" aria-hidden="true">×</button> <strong id="cite-apa_label">Cite: APA Format</strong> </div> <div class="modal-body">Holland, Kieran, Ipp, Andreas, Müller, David I, & Wenger, Urs. <em>Machine learning a fixed point action for SU(3) gauge theory with a gauge equivariant convolutional neural network</em>. <em>Physical Review D</em>, <em>110</em> (7). Retrieved from https://par.nsf.gov/biblio/10546359. <a href="https://doi.org/10.1103/PhysRevD.110.074502">https://doi.org/10.1103/PhysRevD.110.074502</a> </div> <div class="modal-footer"> <button class="btn btn-sm btn-default" data-dismiss="modal" aria-hidden="true">Close</button> </div> </div> </div> </div></li> <li class="links-format"><a href="#cite-chi" data-toggle="modal">Chicago</a> <div id="cite-chi" class="modal" tabindex="-1" role="dialog" aria-labelledby="cite-chi_label" aria-hidden="true"> <div class="modal-dialog"> <div class="modal-content"> <div class="modal-header"> <button type="button" class="close" data-dismiss="modal" aria-hidden="true">×</button> <strong id="cite-chi_label">Cite: Chicago Format</strong> </div> <div class="modal-body">Holland, Kieran, Ipp, Andreas, Müller, David I, and Wenger, Urs. "Machine learning a fixed point action for SU(3) gauge theory with a gauge equivariant convolutional neural network". <em>Physical Review D</em> 110 (7). Country unknown/Code not available: American Physical Society. <a href="https://doi.org/10.1103/PhysRevD.110.074502">https://doi.org/10.1103/PhysRevD.110.074502.</a> <a href="https://par.nsf.gov/biblio/10546359">https://par.nsf.gov/biblio/10546359</a>. </div> <div class="modal-footer"> <button class="btn btn-sm btn-default" data-dismiss="modal" aria-hidden="true">Close</button> </div> </div> </div> </div></li> <li class="links-format"><a href="#cite-bib" data-toggle="modal">BibTeX</a> <div id="cite-bib" class="modal" tabindex="-1" role="dialog" aria-labelledby="cite-bib_label" aria-hidden="true"> <div class="modal-dialog"> <div class="modal-content"> <div class="modal-header"> <button type="button" class="close" data-dismiss="modal" aria-hidden="true">×</button> <strong id="cite-bib_label">Cite: BibTeX Format</strong> </div> <div class="modal-body"> @article{osti_10546359,<br/> place = {Country unknown/Code not available}, title = {Machine learning a fixed point action for SU(3) gauge theory with a gauge equivariant convolutional neural network}, url = {https://par.nsf.gov/biblio/10546359}, DOI = {10.1103/PhysRevD.110.074502}, abstractNote = {Fixed point lattice actions are designed to have continuum classical properties unaffected by discretization effects and reduced lattice artifacts at the quantum level. They provide a possible way to extract continuum physics with coarser lattices, thereby allowing one to circumvent problems with critical slowing down and topological freezing toward the continuum limit. A crucial ingredient for practical applications is to find an accurate and compact parametrization of a fixed point action, since many of its properties are only implicitly defined. Here we use machine learning methods to revisit the question of how to parametrize fixed point actions. In particular, we obtain a fixed point action for four-dimensional SU(3) gauge theory using convolutional neural networks with exact gauge invariance. The large operator space allows us to find superior parametrizations compared to previous studies, a necessary first step for future Monte Carlo simulations and scaling studies. Published by the American Physical Society2024}, journal = {Physical Review D}, volume = {110}, number = {7}, publisher = {American Physical Society}, author = {Holland, Kieran and Ipp, Andreas and Müller, David I and Wenger, Urs}, }</div> <div class="modal-footer"> <button class="btn btn-sm btn-default" data-dismiss="modal" aria-hidden="true">Close</button> </div> </div> </div> </div></li> <li class="divider"></li> </ul> <ul class="nav nav-list" style="font-size: 14px; font-family: Arial Regular;"> <li class="nav-header header-format">Export Metadata</li> <li class="links-format"><a href="https://par.nsf.gov/endnote?osti_id=10546359">EndNote</a></li> <li class="links-format"><a href="https://par.nsf.gov/export/format:excel/osti-id:10546359">Excel</a></li> <li class="links-format"><a href="https://par.nsf.gov/export/format:csv/osti-id:10546359">CSV</a></li> <li class="links-format"><a href="https://par.nsf.gov/export/format:xml/osti-id:10546359">XML</a></li> <li class="divider"></li> </ul> <ul class="nav nav-list" style="font-size: 14px; 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