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href="/nlab/show/analysis">analysis</a></p> <ul> <li> <p><a class="existingWikiWord" href="/nlab/show/nonstandard+analysis">nonstandard analysis</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/functional+analysis">functional analysis</a></p> <ul> <li><a class="existingWikiWord" href="/nlab/show/operator+algebras">operator algebras</a></li> </ul> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/Fourier+transform">Fourier transform</a></p> </li> </ul> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/Lie+theory">Lie theory</a></p> <ul> <li><a class="existingWikiWord" href="/nlab/show/infinity-Lie+theory+-+contents">higher Lie theory</a></li> </ul> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/probability+theory">probability theory</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/discrete+mathematics">discrete mathematics</a></p> </li> </ul> </div></div> <div class="hide"><div> <p><strong><a class="existingWikiWord" href="/nlab/show/physics">physics</a></strong>, <a class="existingWikiWord" href="/nlab/show/mathematical+physics">mathematical physics</a>, <a class="existingWikiWord" href="/nlab/show/philosophy+of+physics">philosophy of physics</a></p> <h2 id="surveys_textbooks_and_lecture_notes">Surveys, textbooks and lecture notes</h2> <ul> <li> <p><em><a class="existingWikiWord" href="/nlab/show/higher+category+theory+and+physics">(higher) category theory and physics</a></em></p> </li> <li> <p><em><a class="existingWikiWord" href="/nlab/show/geometry+of+physics">geometry of physics</a></em></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/books+and+reviews+in+mathematical+physics">books and reviews</a>, <a class="existingWikiWord" href="/nlab/show/physics+resources">physics resources</a></p> </li> </ul> <hr /> <p><a class="existingWikiWord" href="/nlab/show/theory+%28physics%29">theory (physics)</a>, <a class="existingWikiWord" href="/nlab/show/model+%28physics%29">model (physics)</a></p> <p><a class="existingWikiWord" href="/nlab/show/experiment">experiment</a>, <a class="existingWikiWord" href="/nlab/show/measurement">measurement</a>, <a class="existingWikiWord" href="/nlab/show/computable+physics">computable physics</a></p> <ul> <li> <p><strong><a class="existingWikiWord" href="/nlab/show/mechanics">mechanics</a></strong></p> <ul> <li> <p><a class="existingWikiWord" href="/nlab/show/mass">mass</a>, <a class="existingWikiWord" href="/nlab/show/charge">charge</a>, <a class="existingWikiWord" href="/nlab/show/momentum">momentum</a>, <a class="existingWikiWord" href="/nlab/show/angular+momentum">angular momentum</a>, <a class="existingWikiWord" href="/nlab/show/moment+of+inertia">moment of inertia</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/dynamics+on+Lie+groups">dynamics on Lie groups</a></p> <ul> <li><a class="existingWikiWord" href="/nlab/show/rigid+body+dynamics">rigid body dynamics</a></li> </ul> </li> </ul> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/field+%28physics%29">field (physics)</a></p> <ul> <li> <p><a class="existingWikiWord" href="/nlab/show/Lagrangian+mechanics">Lagrangian mechanics</a></p> <ul> <li> <p><a class="existingWikiWord" href="/nlab/show/configuration+space">configuration space</a>, <a class="existingWikiWord" href="/nlab/show/state">state</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/action+functional">action functional</a>, <a class="existingWikiWord" href="/nlab/show/Lagrangian">Lagrangian</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/covariant+phase+space">covariant phase space</a>, <a class="existingWikiWord" href="/nlab/show/Euler-Lagrange+equations">Euler-Lagrange equations</a></p> </li> </ul> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/Hamiltonian+mechanics">Hamiltonian mechanics</a></p> <ul> <li> <p><a class="existingWikiWord" href="/nlab/show/phase+space">phase space</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/symplectic+geometry">symplectic geometry</a></p> <ul> <li> <p><a class="existingWikiWord" href="/nlab/show/Poisson+manifold">Poisson manifold</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/symplectic+manifold">symplectic manifold</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/symplectic+groupoid">symplectic groupoid</a></p> </li> </ul> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/multisymplectic+geometry">multisymplectic geometry</a></p> <ul> <li><a class="existingWikiWord" href="/nlab/show/n-symplectic+manifold">n-symplectic manifold</a></li> </ul> </li> </ul> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/spacetime">spacetime</a></p> <ul> <li> <p><a class="existingWikiWord" href="/nlab/show/smooth+Lorentzian+manifold">smooth Lorentzian manifold</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/special+relativity">special relativity</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/general+relativity">general relativity</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/gravity">gravity</a></p> <ul> <li> <p><a class="existingWikiWord" href="/nlab/show/supergravity">supergravity</a>, <a class="existingWikiWord" href="/nlab/show/dilaton+gravity">dilaton gravity</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/black+hole">black hole</a></p> </li> </ul> </li> </ul> </li> </ul> </li> <li> <p><strong><a class="existingWikiWord" href="/nlab/show/classical+field+theory">Classical field theory</a></strong></p> <ul> <li> <p><a class="existingWikiWord" href="/nlab/show/classical+physics">classical physics</a></p> <ul> <li><a class="existingWikiWord" href="/nlab/show/classical+mechanics">classical mechanics</a></li> <li><a class="existingWikiWord" href="/nlab/show/waves">waves</a> and <a class="existingWikiWord" href="/nlab/show/optics">optics</a></li> <li><a class="existingWikiWord" href="/nlab/show/thermodynamics">thermodynamics</a></li> </ul> </li> </ul> </li> <li> <p><strong><a class="existingWikiWord" href="/nlab/show/quantum+mechanics">Quantum Mechanics</a></strong></p> <ul> <li> <p><a class="existingWikiWord" href="/nlab/show/quantum+mechanics+in+terms+of+dagger-compact+categories">in terms of ∞-compact categories</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/quantum+information">quantum information</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/Hamiltonian+operator">Hamiltonian operator</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/density+matrix">density matrix</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/Kochen-Specker+theorem">Kochen-Specker theorem</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/Bell%27s+theorem">Bell's theorem</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/Gleason%27s+theorem">Gleason's theorem</a></p> </li> </ul> </li> <li> <p><strong><a class="existingWikiWord" href="/nlab/show/quantization">Quantization</a></strong></p> <ul> <li> <p><a class="existingWikiWord" href="/nlab/show/geometric+quantization">geometric quantization</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/deformation+quantization">deformation quantization</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/path+integral">path integral quantization</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/semiclassical+approximation">semiclassical approximation</a></p> </li> </ul> </li> <li> <p><strong><a class="existingWikiWord" href="/nlab/show/quantum+field+theory">Quantum Field Theory</a></strong></p> <ul> <li> <p>Axiomatizations</p> <ul> <li> <p><a class="existingWikiWord" href="/nlab/show/AQFT">algebraic QFT</a></p> <ul> <li> <p><a class="existingWikiWord" href="/nlab/show/Wightman+axioms">Wightman axioms</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/Haag-Kastler+axioms">Haag-Kastler axioms</a></p> <ul> <li> <p><a class="existingWikiWord" href="/nlab/show/operator+algebra">operator algebra</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/local+net">local net</a></p> </li> </ul> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/conformal+net">conformal net</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/Reeh-Schlieder+theorem">Reeh-Schlieder theorem</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/Osterwalder-Schrader+theorem">Osterwalder-Schrader theorem</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/PCT+theorem">PCT theorem</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/Bisognano-Wichmann+theorem">Bisognano-Wichmann theorem</a></p> <ul> <li><a class="existingWikiWord" href="/nlab/show/modular+theory">modular theory</a></li> </ul> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/spin-statistics+theorem">spin-statistics theorem</a></p> <ul> <li><a class="existingWikiWord" href="/nlab/show/boson">boson</a>, <a class="existingWikiWord" href="/nlab/show/fermion">fermion</a></li> </ul> </li> </ul> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/FQFT">functorial QFT</a></p> <ul> <li> <p><a class="existingWikiWord" href="/nlab/show/cobordism">cobordism</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/%28%E2%88%9E%2Cn%29-category+of+cobordisms">(∞,n)-category of cobordisms</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/cobordism+hypothesis">cobordism hypothesis</a>-theorem</p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/extended+topological+quantum+field+theory">extended topological quantum field theory</a></p> </li> </ul> </li> </ul> </li> <li> <p>Tools</p> <ul> <li> <p><a class="existingWikiWord" href="/nlab/show/perturbative+quantum+field+theory">perturbative quantum field theory</a>, <a class="existingWikiWord" href="/nlab/show/vacuum">vacuum</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/effective+quantum+field+theory">effective quantum field theory</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/renormalization">renormalization</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/BV-BRST+formalism">BV-BRST formalism</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/geometric+%E2%88%9E-function+theory">geometric ∞-function theory</a></p> </li> </ul> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/particle+physics">particle physics</a></p> <ul> <li> <p><a class="existingWikiWord" href="/nlab/show/phenomenology">phenomenology</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/model+%28in+particle+phyiscs%29">models</a></p> <ul> <li> <p><a class="existingWikiWord" href="/nlab/show/standard+model+of+particle+physics">standard model of particle physics</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/fields+and+quanta+-+table">fields and quanta</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/GUT">Grand Unified Theories</a>, <a class="existingWikiWord" href="/nlab/show/MSSM">MSSM</a></p> </li> </ul> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/scattering+amplitude">scattering amplitude</a></p> <ul> <li><a class="existingWikiWord" href="/nlab/show/on-shell+recursion">on-shell recursion</a>, <a class="existingWikiWord" href="/nlab/show/KLT+relations">KLT relations</a></li> </ul> </li> </ul> </li> <li> <p>Structural phenomena</p> <ul> <li> <p><a class="existingWikiWord" href="/nlab/show/universality+class">universality class</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/quantum+anomaly">quantum anomaly</a></p> <ul> <li><a class="existingWikiWord" href="/nlab/show/Green-Schwarz+mechanism">Green-Schwarz mechanism</a></li> </ul> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/instanton">instanton</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/spontaneously+broken+symmetry">spontaneously broken symmetry</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/Kaluza-Klein+mechanism">Kaluza-Klein mechanism</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/integrable+systems">integrable systems</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/holonomic+quantum+fields">holonomic quantum fields</a></p> </li> </ul> </li> <li> <p>Types of quantum field thories</p> <ul> <li> <p><a class="existingWikiWord" href="/nlab/show/TQFT">TQFT</a></p> <ul> <li> <p><a class="existingWikiWord" href="/nlab/show/2d+TQFT">2d TQFT</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/Dijkgraaf-Witten+theory">Dijkgraaf-Witten theory</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/Chern-Simons+theory">Chern-Simons theory</a></p> </li> </ul> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/TCFT">TCFT</a></p> <ul> <li> <p><a class="existingWikiWord" href="/nlab/show/A-model">A-model</a>, <a class="existingWikiWord" href="/nlab/show/B-model">B-model</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/homological+mirror+symmetry">homological mirror symmetry</a></p> </li> </ul> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/QFT+with+defects">QFT with defects</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/conformal+field+theory">conformal field theory</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/%281%2C1%29-dimensional+Euclidean+field+theories+and+K-theory">(1,1)-dimensional Euclidean field theories and K-theory</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/%282%2C1%29-dimensional+Euclidean+field+theory">(2,1)-dimensional Euclidean field theory and elliptic cohomology</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/CFT">CFT</a></p> <ul> <li> <p><a class="existingWikiWord" href="/nlab/show/WZW+model">WZW model</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/6d+%282%2C0%29-supersymmetric+QFT">6d (2,0)-supersymmetric QFT</a></p> </li> </ul> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/gauge+theory">gauge theory</a></p> <ul> <li> <p><a class="existingWikiWord" href="/nlab/show/field+strength">field strength</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/gauge+group">gauge group</a>, <a class="existingWikiWord" href="/nlab/show/gauge+transformation">gauge transformation</a>, <a class="existingWikiWord" href="/nlab/show/gauge+fixing">gauge fixing</a></p> </li> <li> <p>examples</p> <ul> <li><a class="existingWikiWord" href="/nlab/show/electromagnetic+field">electromagnetic field</a>, <a class="existingWikiWord" href="/nlab/show/QED">QED</a></li> </ul> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/electric+charge">electric charge</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/magnetic+charge">magnetic charge</a></p> <ul> <li><a class="existingWikiWord" href="/nlab/show/Yang-Mills+field">Yang-Mills field</a>, <a class="existingWikiWord" href="/nlab/show/QCD">QCD</a></li> </ul> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/Yang-Mills+theory">Yang-Mills theory</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/spinors+in+Yang-Mills+theory">spinors in Yang-Mills theory</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/topological+Yang-Mills+theory">topological Yang-Mills theory</a></p> <ul> <li><a class="existingWikiWord" href="/nlab/show/Kalb-Ramond+field">Kalb-Ramond field</a></li> <li><a class="existingWikiWord" href="/nlab/show/supergravity+C-field">supergravity C-field</a></li> <li><a class="existingWikiWord" href="/nlab/show/RR+field">RR field</a></li> <li><a class="existingWikiWord" href="/nlab/show/first-order+formulation+of+gravity">first-order formulation of gravity</a></li> </ul> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/general+covariance">general covariance</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/supergravity">supergravity</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/D%27Auria-Fre+formulation+of+supergravity">D'Auria-Fre formulation of supergravity</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/gravity+as+a+BF-theory">gravity as a BF-theory</a></p> </li> </ul> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/sigma-model">sigma-model</a></p> <ul> <li> <p><a class="existingWikiWord" href="/nlab/show/particle">particle</a>, <a class="existingWikiWord" href="/nlab/show/relativistic+particle">relativistic particle</a>, <a class="existingWikiWord" href="/nlab/show/fundamental+particle">fundamental particle</a>, <a class="existingWikiWord" href="/nlab/show/spinning+particle">spinning particle</a>, <a class="existingWikiWord" href="/nlab/show/superparticle">superparticle</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/string">string</a>, <a class="existingWikiWord" href="/nlab/show/spinning+string">spinning string</a>, <a class="existingWikiWord" href="/nlab/show/superstring">superstring</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/membrane">membrane</a></p> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/AKSZ+theory">AKSZ theory</a></p> </li> </ul> </li> </ul> </li> </ul> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/string+theory">String Theory</a></p> <ul> <li><a class="existingWikiWord" href="/nlab/show/string+theory+results+applied+elsewhere">string theory results applied elsewhere</a></li> </ul> </li> <li> <p><a class="existingWikiWord" href="/nlab/show/number+theory+and+physics">number theory and physics</a></p> <ul> <li><a class="existingWikiWord" href="/nlab/show/Riemann+hypothesis+and+physics">Riemann hypothesis and physics</a></li> </ul> </li> </ul> <div> <p> <a href="/nlab/edit/physicscontents">Edit this sidebar</a> </p> </div></div></div> </div> </div> <div class="query"> <p><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline" class="maruku-mathml"><semantics><mrow><mspace width="thinmathspace"></mspace></mrow><annotation encoding="application/x-tex">\,</annotation></semantics></math></p> <div align="center"> <em>Search the nLab (<a class="existingWikiWord" href="/nlab/show/Searching+the+nLab">hints</a>)</em> <form name="gsearch" method="get" action="https://www.google.com/search" id="gsearch"><input type="text" size="30" name="as_q" /><input type="hidden" name="as_sitesearch" value="https://ncatlab.org/nlab/" /></form> </div> <p> <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline" class="maruku-mathml"><semantics><mrow><mspace width="thinmathspace"></mspace></mrow><annotation encoding="application/x-tex">\,</annotation></semantics></math></p> </div> <p><a class="existingWikiWord" href="/nlab/show/About">This</a> is a <a href="http://en.wikipedia.org/wiki/Wiki">wiki</a> for collaborative work on <em><a class="existingWikiWord" href="/nlab/show/Mathematics">Mathematics</a></em>, <em><a class="existingWikiWord" href="/nlab/show/Physics">Physics</a></em>, and <em><a class="existingWikiWord" href="/nlab/show/Philosophy">Philosophy</a></em> — especially (but far from exclusively) from the <a class="existingWikiWord" href="/nlab/show/higher+structures">higher structures</a> <a class="existingWikiWord" href="/nlab/show/n-point+of+view">point of view</a>: with a sympathy towards the tools and perspectives of <a class="existingWikiWord" href="/nlab/show/homotopy+theory">homotopy theory</a>/<a class="existingWikiWord" href="/nlab/show/algebraic+topology">algebraic topology</a>, <a class="existingWikiWord" href="/nlab/show/homotopy+type+theory">homotopy</a> <a class="existingWikiWord" href="/nlab/show/type+theory">type theory</a>, <a class="existingWikiWord" href="/nlab/show/higher+category+theory">higher</a> <a class="existingWikiWord" href="/nlab/show/category+theory">category theory</a> and <a class="existingWikiWord" href="/nlab/show/higher+algebra">higher</a> <a class="existingWikiWord" href="/nlab/show/categorical+algebra">categorical algebra</a>.</p> <h1 id='section_table_of_contents'>Contents</h1> <div class='maruku_toc'> <ul> <li><a href='#purpose'>Purpose</a></li> <li><a href='#Discussion'>nForum, discussion, comments, and questions</a></li> <li><a href='#Contributing'>Contributing to the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline" class="maruku-mathml"><semantics><mrow><mi>n</mi></mrow><annotation encoding="application/x-tex">n</annotation></semantics></math>Lab</a></li> <li><a href='#SoftwareRequirements'>Viewing and editing the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline" class="maruku-mathml"><semantics><mrow><mi>n</mi></mrow><annotation encoding="application/x-tex">n</annotation></semantics></math>Lab</a></li> <li><a href='#TermsOfUse'>Making use of material from the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline" class="maruku-mathml"><semantics><mrow><mi>n</mi></mrow><annotation encoding="application/x-tex">n</annotation></semantics></math>Lab</a></li> <li><a href='#Installation'>Installation</a></li> <li><a href='#Contact'>Contact</a></li> <li><a href='#SteeringCommitte'>Steering Committee</a></li> </ul> </div> <h2 id="purpose">Purpose</h2> <p>The nLab records and explores a wide range of mathematics, physics, and philosophy. Along with work of an expository nature, original material can be found in abundance, as can notes from evolving research. Where mathematics, physics, and philosophy arise in other fields, computer science and linguistics for example, the nLab explores these too.</p> <p>If you take a little time to find something in the literature, or to work through a proof or example, or to find an intuitive or new way to think about something, add a note on it to the nLab! Others will benefit, and you may well find that it proves useful to you too.</p> <p>A fundamental idea behind the nLab is that the linking between pages of a wiki is a profound way to record knowledge, placing it in a rich context.</p> <p>For more, see also <a class="existingWikiWord" href="/nlab/show/Urs+Schreiber">Urs Schreiber</a>‘s thoughts at <a class="existingWikiWord" href="/schreiber/show/What+is...+the+nLab">What is… the nLab?</a>.</p> <h2 id="Discussion">nForum, discussion, comments, and questions</h2> <p>Most nLab pages have a corresponding discussion thread at the <a href="https://nforum.ncatlab.org">nForum</a>, linked to in the menus at the top and bottom of the page. For all but the most trivial edits (correcting spelling or punctuation, etc), we ask that you announce your changes at the nForum using the box at the bottom of the edit page. Typically this would be a short note summarising what you have done, but it can also include what you plan to do, or what you would like others to do! See <a class="existingWikiWord" href="/nlabmeta/show/Welcome+to+the+nForum">Welcome to the nForum</a> for more on the nForum.</p> <p>If you have any questions about an nLab page, or would like to discuss or make a comment upon something in it, whether because you feel that something is wrong or missing or for any other reason, you are encouraged and very welcome to use the nForum discussion thread for the page for this purpose too. If the discussion thread does not yet exist, feel free to create it manually: use the ‘nLab - Latest changes’ category, and give it the same title (case-sensitive!) as the nLab page.</p> <p>The pages of the nLab have almost always been edited by several people. In almost all cases, we recommend that you use the nForum rather than contact an author of an edit directly, but if you do have a reason to do this, the history of edits to the page with the details of who made them can be found by clicking on ‘History’ at the bottom of the page.</p> <h2 id="Contributing">Contributing to the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline" class="maruku-mathml"><semantics><mrow><mi>n</mi></mrow><annotation encoding="application/x-tex">n</annotation></semantics></math>Lab</h2> <p>If after looking around for a while you feel like contributing yourself, you are very welcome to do so! See <a href="#SoftwareRequirements">below</a> for more on how to actually edit, as well as the <a class="existingWikiWord" href="/nlab/show/HowTo">HowTo</a>.</p> <p>If you make any edits to the nLab, please follow the guidelines for announcing your changes at the <a href="https://nforum.ncatlab.org">nForum</a> given <a href="#Discussion">above</a>. If you are unsure whether what you would like to contribute is appropriate, please ask at the nForum before making the edit.</p> <h2 id="SoftwareRequirements">Viewing and editing the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline" class="maruku-mathml"><semantics><mrow><mi>n</mi></mrow><annotation encoding="application/x-tex">n</annotation></semantics></math>Lab</h2> <p>The nLab should be viewable and editable in any modern web browser on any device. For technical reasons, browsers which are able to render <a href="http://en.wikipedia.org/wiki/MathML">MathML</a>, such as Firefox, may render very large pages quicker than other browsers, but these pages are few and far between, and most people will be able to use the browser of their choice.</p> <p>Editing the nLab these days can be done more or less as in LaTeX. Macros are not currently available, but mathematics can be entered within dollar signs as usual, <a href="https://ncatlab.org/nlab/show/HowTo#DefinitionTheoremProofEnvironments">theorem environments</a>, sections and tables of contents can be defined as in LaTeX, <a href="https://ncatlab.org/nlab/show/HowTo#diagrams">commutative diagrams</a> and figures can be created in Tikz or XyMatrix, and so on. For simple formatting, such as italics, and for some other things such as tables, <a href="https://en.wikipedia.org/wiki/Markdown">Markdown</a> is used.</p> <p>See the <a class="existingWikiWord" href="/nlab/show/HowTo">HowTo</a> for more on editing the nLab.</p> <h2 id="TermsOfUse">Making use of material from the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline" class="maruku-mathml"><semantics><mrow><mi>n</mi></mrow><annotation encoding="application/x-tex">n</annotation></semantics></math>Lab</h2> <p>One goal of the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline" class="maruku-mathml"><semantics><mrow><mi>n</mi></mrow><annotation encoding="application/x-tex">n</annotation></semantics></math>Lab is to help make information widely available and usefully related to other information. In this users and contributors are expected to follow traditional academic practice:</p> <ul> <li> <p>Using and distributing content obtained from the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline" class="maruku-mathml"><semantics><mrow><mi>n</mi></mrow><annotation encoding="application/x-tex">n</annotation></semantics></math>Lab is free and encouraged if you acknowledge the source, as usual in academia.</p> <p>(There is currently no consensus on a more formal license statement, but if it matters check if relevant individual contributors state such on their <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline" class="maruku-mathml"><semantics><mrow><mi>n</mi></mrow><annotation encoding="application/x-tex">n</annotation></semantics></math>Lab homepages.)</p> <p>If you cite a page you may want to point to a specific version of it, because <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline" class="maruku-mathml"><semantics><mrow><mi>n</mi></mrow><annotation encoding="application/x-tex">n</annotation></semantics></math>Lab pages can change. You can find a list of all the versions of a page by clicking on the <strong>History</strong> link at the bottom of the page itself.</p> </li> <li> <p>Conversely, any content contributed to the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline" class="maruku-mathml"><semantics><mrow><mi>n</mi></mrow><annotation encoding="application/x-tex">n</annotation></semantics></math>Lab is publicly available and you should be aware that others may use your contributions (whatever you decide to do with their content elsewhere) and indeed may edit them. In the first case you trust that users will cite your contributions properly, in the second that they will respect and only improve on them. At the same time, you are expected to properly acknowledge sources of information for material entered into the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline" class="maruku-mathml"><semantics><mrow><mi>n</mi></mrow><annotation encoding="application/x-tex">n</annotation></semantics></math>Lab.</p> </li> </ul> <p>Usually this works well. If there is need for discussion, the <a href="http://nforum.ncatlab.org">nForum</a> is the forum to turn to. If serious problems arise, the <a href="#SteeringCommitte">steering committee</a> might intervene.</p> <h2 id="Installation">Installation</h2> <p>The domain <code>ncatlab.org</code> is owned by <a class="existingWikiWord" href="/nlab/show/Urs+Schreiber">Urs Schreiber</a>.</p> <p>The <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline" class="maruku-mathml"><semantics><mrow><mi>n</mi></mrow><annotation encoding="application/x-tex">n</annotation></semantics></math>Lab server is currently hosted at Carnegie Mellon University, kindly provided by <a class="existingWikiWord" href="/nlab/show/Steve+Awodey">Steve Awodey</a>.</p> <p>The nLab’s software and technical administrative matters are in the hands of the nLab’s <a class="existingWikiWord" href="/nlabmeta/show/technical+board">technical board</a>.</p> <p>Much of the software behind the nLab has been written especially for the nLab: the latest source can be found at <a href="https://github.com/ncatlab/nlab">GitHub</a>. It was originally an instance of <a href="https://golem.ph.utexas.edu/wiki/instiki/show/HomePage">Instiki</a>.</p> <p>The <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline" class="maruku-mathml"><semantics><mrow><mi>n</mi></mrow><annotation encoding="application/x-tex">n</annotation></semantics></math>Lab page style is due to <a class="existingWikiWord" href="/nlab/show/Jake+Bian">Jake Bian</a>, originating with his <a href="https://github.com/jakebian/kan">Kan browser extension</a></p> <p>The <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline" class="maruku-mathml"><semantics><mrow><mi>n</mi></mrow><annotation encoding="application/x-tex">n</annotation></semantics></math>Lab logo is due to <a class="existingWikiWord" href="/nlab/show/David+Roberts">David Roberts</a>, inspired by Matisse’s painting <em><a href="https://collections.lacma.org/node/207557">La Gerbe</a></em>. Besides being an inside reference to <a class="existingWikiWord" href="/schreiber/show/Higher+Structures">higher structures</a> known as <em><a class="existingWikiWord" href="/nlab/show/gerbes">gerbes</a></em>, the logo represents maybe <a class="existingWikiWord" href="/nlab/show/computational+trinitarianism">computational trinitarianism</a> or the <a class="existingWikiWord" href="/nlab/show/Science+of+Logic">progression of modalities</a> or generally the unity of diverse mathematical phenomena revealed by the <a class="existingWikiWord" href="/nlab/show/nPOV">nPOV</a>.</p> <p><br /></p> <h2 id="Contact">Contact</h2> <p>The default venue for all communication regarding the nLab is the <a href="https://nforum.ncatlab.org/">nForum</a>. When posting there you get to choose a “category”-label for your message:</p> <ul> <li> <p>Latest edit logs are to be posted under <em><a href="https://nforum.ncatlab.org/5/">Latest changes</a></em>.</p> </li> <li> <p>Organizational matters (such as concerning user accounts) are best posted under <em><a href="https://nforum.ncatlab.org/14/">nLab Organisation</a></em>.</p> </li> <li> <p>Technical bug reports or software feature requests are best raised in <em><a href="https://nforum.ncatlab.org/21/">nLab Technical Matters</a></em></p> <p>or directly on <a href="https://github.com/ncatlab/nlab/issues">github.com/ncatlab/nlab/issues</a>.</p> </li> </ul> <p>Please do not try to contact the technical team on matters that are not purely technical: Policy decisions are made by the active nLab community or, if all fails, by the <a href="#SteeringCommitte">Steering Committee</a>.</p> <p><br /></p> <h2 id="SteeringCommitte">Steering Committee</h2> <p>The <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline" class="maruku-mathml"><semantics><mrow><mi>n</mi></mrow><annotation encoding="application/x-tex">n</annotation></semantics></math>Lab is a community undertaking. But for all matters that do require that the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline" class="maruku-mathml"><semantics><mrow><mi>n</mi></mrow><annotation encoding="application/x-tex">n</annotation></semantics></math>Lab is represented to the outside by an official decision-taking body, we have the <a class="existingWikiWord" href="/nlabmeta/show/steering+committee">steering committee</a>. <em>Nobody “is in charge of the <math xmlns="http://www.w3.org/1998/Math/MathML" display="inline" class="maruku-mathml"><semantics><mrow><mi>n</mi></mrow><annotation encoding="application/x-tex">n</annotation></semantics></math>Lab”.</em> But the steering committee is the closest approximation to a body being in charge that we have.</p> <div class="property">category: <a class="category_link" href="/nlab/all_pages/meta">meta</a></div></body></html> </div> <div class="revisedby"> <p> Last revised on March 30, 2024 at 02:03:46. See the <a href="/nlab/history/HomePage" style="color: #005c19">history</a> of this page for a list of all contributions to it. </p> </div> <div class="navigation navfoot"> <a href="/nlab/edit/HomePage" accesskey="E" class="navlink" id="edit" rel="nofollow">Edit Page</a><a href="/nlab/edit_web" accesskey="W" class="navlink" id="edit_web" rel="nofollow">Edit Web</a><a href="https://nforum.ncatlab.org/discussion/3545/#Item_102">Discuss</a><span class="backintime"><a href="/nlab/revision/HomePage/308" accesskey="B" class="navlinkbackintime" id="to_previous_revision" rel="nofollow">Previous revision</a></span><a href="/nlab/show/diff/HomePage" accesskey="C" class="navlink" id="see_changes" rel="nofollow">Changes from previous revision</a><a href="/nlab/history/HomePage" accesskey="S" class="navlink" id="history" rel="nofollow">History (308 revisions)</a> <a href="/nlab/show/HomePage/cite" style="color: black">Cite</a> <a href="/nlab/print/HomePage" accesskey="p" id="view_print" rel="nofollow">Print</a> <a href="/nlab/source/HomePage" id="view_source" rel="nofollow">Source</a> </div> </div>  </div>  </body> </html>