BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//CMSA - ECPv6.16.3//NONSGML v1.0//EN
CALSCALE:GREGORIAN
METHOD:PUBLISH
X-ORIGINAL-URL:https://cmsa.fas.harvard.edu
X-WR-CALDESC:Events for CMSA
REFRESH-INTERVAL;VALUE=DURATION:PT1H
X-Robots-Tag:noindex
X-PUBLISHED-TTL:PT1H
BEGIN:VTIMEZONE
TZID:America/New_York
BEGIN:DAYLIGHT
TZOFFSETFROM:-0500
TZOFFSETTO:-0400
TZNAME:EDT
DTSTART:20220313T070000
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:-0400
TZOFFSETTO:-0500
TZNAME:EST
DTSTART:20221106T060000
END:STANDARD
BEGIN:DAYLIGHT
TZOFFSETFROM:-0500
TZOFFSETTO:-0400
TZNAME:EDT
DTSTART:20230312T070000
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:-0400
TZOFFSETTO:-0500
TZNAME:EST
DTSTART:20231105T060000
END:STANDARD
BEGIN:DAYLIGHT
TZOFFSETFROM:-0500
TZOFFSETTO:-0400
TZNAME:EDT
DTSTART:20240310T070000
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:-0400
TZOFFSETTO:-0500
TZNAME:EST
DTSTART:20241103T060000
END:STANDARD
BEGIN:DAYLIGHT
TZOFFSETFROM:-0500
TZOFFSETTO:-0400
TZNAME:EDT
DTSTART:20250309T070000
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:-0400
TZOFFSETTO:-0500
TZNAME:EST
DTSTART:20251102T060000
END:STANDARD
END:VTIMEZONE
BEGIN:VTIMEZONE
TZID:America/New_York
BEGIN:DAYLIGHT
TZOFFSETFROM:-0500
TZOFFSETTO:-0400
TZNAME:EDT
DTSTART:20220313T070000
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:-0400
TZOFFSETTO:-0500
TZNAME:EST
DTSTART:20221106T060000
END:STANDARD
BEGIN:DAYLIGHT
TZOFFSETFROM:-0500
TZOFFSETTO:-0400
TZNAME:EDT
DTSTART:20230312T070000
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:-0400
TZOFFSETTO:-0500
TZNAME:EST
DTSTART:20231105T060000
END:STANDARD
BEGIN:DAYLIGHT
TZOFFSETFROM:-0500
TZOFFSETTO:-0400
TZNAME:EDT
DTSTART:20240310T070000
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:-0400
TZOFFSETTO:-0500
TZNAME:EST
DTSTART:20241103T060000
END:STANDARD
BEGIN:DAYLIGHT
TZOFFSETFROM:-0500
TZOFFSETTO:-0400
TZNAME:EDT
DTSTART:20250309T070000
END:DAYLIGHT
BEGIN:STANDARD
TZOFFSETFROM:-0400
TZOFFSETTO:-0500
TZNAME:EST
DTSTART:20251102T060000
END:STANDARD
END:VTIMEZONE
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20241115T143000
DTEND;TZID=America/New_York:20241115T173000
DTSTAMP:20260618T133951
CREATED:20240923T164810Z
LAST-MODIFIED:20241112T153736Z
UID:10003602-1731681000-1731691800@cmsa.fas.harvard.edu
SUMMARY:Freedman CMSA Seminar
DESCRIPTION:Freedman CMSA Seminar \n*Note: via Zoom only* \n  \n2:00-3:30 pm ET \nSpeaker: Michael Freedman\, Harvard CMSA \nTitle: Some questions and theorems about closed 3 manifolds embedded in S^4 \nAbstract: Much is unknown about smooth embeddings of 3-manifolds in S^4; the Schoenflies problem  (Is there only one smoothly embedded 3-sphere in S^4 up to isotopy?) is the best-known example. There has long been a hope that 3-manifold reasoning applied to level-sets will be helpful.  I’ll mention some successes and failures of this method and revisit a classical theorem of Hantzsche in this light. (Hantzsche: If a 3-manifold embeds in S^4 its linking form is hyperbolic.) \n  \n3:30-4:00 pm ET \nBreak/Discussion \n  \n4:00-5:30 pm ET \nSpeaker: Slava Krushkal\, University of Virginia \nTitle: A higher order torsion linking form for 3-manifolds \nAbstract: This talk is based on a joint work with Mike Freedman defining a triple linking form for rational homology spheres\, assuming that the classical torsion linking pairing of three classes pairwise vanishes. I will discuss its vanishing for 3-manifolds in S^4\, and its relation to the Matsumoto triple intersection form on 4-manifolds. \n  \n 
URL:https://cmsa.fas.harvard.edu/event/freedman_11824/
LOCATION:Virtual
CATEGORIES:Freedman Seminar
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-Freedman-Seminar-11.15.2024.docx-1.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20241113T100000
DTEND;TZID=America/New_York:20241113T230000
DTSTAMP:20260618T133951
CREATED:20241017T141250Z
LAST-MODIFIED:20241115T175125Z
UID:10003613-1731492000-1731538800@cmsa.fas.harvard.edu
SUMMARY:Frontier of Formal Theorem Proving with Large Language Models: Insights from the DeepSeek-Prover Series
DESCRIPTION:New Technologies in Mathematics Seminar \nSpeaker: Huajian Xin\, DeepSeek \nTitle: Frontier of Formal Theorem Proving with Large Language Models: Insights from the DeepSeek-Prover Series \nAbstract: Recent advances in large language models have markedly influenced mathematical reasoning and automated theorem proving within artificial intelligence. Yet\, despite their success in natural language tasks\, these models face notable obstacles in formal theorem proving environments such as Lean and Isabelle\, where exacting derivations must adhere to strict formal specifications. Even state-of-the-art models encounter difficulty generating accurate and complex formal proofs\, revealing the unique blend of mathematical rigor required in this domain. In the DeepSeek-Prover series (V1 and V1.5)\, we have explored specialized methodologies aimed at addressing these challenges. This talk will delve into three foundational areas: the synthesis of training data through autoformalization\, reinforcement learning that utilizes feedback from proof assistants\, and test-time optimization using Monte Carlo tree search. I will also provide insights into current model capabilities\, persistent challenges\, and the future potential of large language models in automated theorem proving.
URL:https://cmsa.fas.harvard.edu/event/newtech_111324/
LOCATION:Virtual
CATEGORIES:New Technologies in Mathematics Seminar
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-NTM-Seminar-11.13.24.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20241108T100000
DTEND;TZID=America/New_York:20241108T113000
DTSTAMP:20260618T133951
CREATED:20240907T194143Z
LAST-MODIFIED:20241104T181059Z
UID:10003470-1731060000-1731065400@cmsa.fas.harvard.edu
SUMMARY:Representations of minimal W-algebras: unitarity and modular invariance
DESCRIPTION:Quantum Field Theory and Physical Mathematics Seminar \nSpeaker: Victor Kac (MIT) \nTitle: Representations of minimal W-algebras: unitarity and modular invariance \nAbstract: The minimal W-algebras\, obtained by quantum Hamiltonian reduction from affina vertex algebras\, form the most interesting class of vertex algebras\, which includes all superconformal algebras: Virasoro\, Neveu-Scharz\, N=2\, 3\, 4\, and big N=4. I will explain a unified classification of their unitary representations\, and their character formulas. For N=0\, 1\, and 2 these vertex algebras are modular invariant (meaning that tr q^L_0-c/24 is a modular function). However for all other minimal W-algebra modular invariance fails\, and one needs the “modification” of characters to restore modular invariance. Unfortunately the representation-theoretical or physical meaning of the modification is not known (at least to me).
URL:https://cmsa.fas.harvard.edu/event/qm_11824/
LOCATION:Virtual
CATEGORIES:Quantum Field Theory and Physical Mathematics
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-QFT-and-Physical-Mathematics-11.8.2024.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20241029T110000
DTEND;TZID=America/New_York:20241029T120000
DTSTAMP:20260618T133951
CREATED:20240903T183326Z
LAST-MODIFIED:20241026T192248Z
UID:10003425-1730199600-1730203200@cmsa.fas.harvard.edu
SUMMARY:Formation of Trapped Surfaces in Geodesic Foliation
DESCRIPTION:General Relativity Seminar \nSpeaker: Xuantao Chen\, Johns Hopkins University \nTitle: Formation of Trapped Surfaces in Geodesic Foliation \nAbstract: We reprove the formation of trapped surfaces for the Einstein vacuum equation using the incoming geodesic foliation. All previous results\, starting with the seminal work of Christodoulou\, make use of the double null foliation. In the new proof\, all Ricci coefficients are estimated by transport equations in the incoming null direction\, and the incoming initial data is only used in the curvature (energy) estimates. The result is based on a version of the non-integrable PT frame\, which was introduced in the proof of Kerr stability with small angular momentum. \n 
URL:https://cmsa.fas.harvard.edu/event/general-relativity-seminar-102224/
LOCATION:Virtual
CATEGORIES:General Relativity Seminar
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-GR-Seminar-10.29.2024.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20241025T143000
DTEND;TZID=America/New_York:20241025T173000
DTSTAMP:20260618T133951
CREATED:20240907T191539Z
LAST-MODIFIED:20241010T152044Z
UID:10003466-1729866600-1729877400@cmsa.fas.harvard.edu
SUMMARY:Freedman CMSA Seminar
DESCRIPTION:Freedman CMSA Seminar \n*Note: via Zoom only* \n2:00-3:30 pm ET \nSpeaker: Matt Hastings\, Microsoft Quantum Program \nTitle: Invertible Phases of Matter and Quantum Cellular Automata: Dimensions One to Three \nAbstract: A Quantum Cellular Automaton (QCA) is a *-automorphism of the algebra of local operators. While local quantum circuits provide one example of QCA\, we are most interested in nontrivial QCA which are those which cannot be written as conjugation by a local quantum circuit. For systems in one and two spatial dimensions\, all nontrivial QCA are shifts (i.e.\, translations by some amount)\, up to conjugation by a quantum circuit\, but in three and higher dimensions\, other examples are known. I’ll explain the relation between QCA and a certain “boundary algebra” of operators in one lower spatial dimension\, and also the relation to invertible phases of matter on the boundary\, and use this to explain and motivate some of these results in dimensions one through three. \n  \n3:30-4:00 pm ET \nBreak/Discussion \n  \n4:00-5:30 pm ET \nSpeaker: Lukasz Fidkowski\, U Washington\, Physics \nTitle: Invertible Phases of Matter and Quantum Cellular Automata: Higher dimensions \nAbstract: We discuss the explicit construction of a non-trivial QCA in 3 dimensions\, one which takes the form of multiplication by a discrete Chern-Simons functional in an appropriate basis for the Hilbert space. We relate the non-trivialness of the QCA to the fact that the Chern-Simons action is not the integral of a gauge invariant local quantity. One property of this QCA is that it creates a specific non-trivial time reversal symmetry protected topological (SPT) phase when acting on a non-trivial tensor product state. Motivated by this\, we construct a general class of QCA in arbitrary dimensions based on time reversal protected SPTs\, and conjecture a general correspondence between unoriented cobordism (which classifies such SPTs) and QCA. \n  \n 
URL:https://cmsa.fas.harvard.edu/event/freedman_102524/
LOCATION:Virtual
CATEGORIES:Freedman Seminar
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-Freedman-Seminar-10.25.2024.docx-1.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20241024T100000
DTEND;TZID=America/New_York:20241024T110000
DTSTAMP:20260618T133951
CREATED:20241018T143428Z
LAST-MODIFIED:20241018T144254Z
UID:10003595-1729764000-1729767600@cmsa.fas.harvard.edu
SUMMARY:Heterotic Little String Theories and Inequivalent Genus-One Fibrations
DESCRIPTION:Mathematical Physics and Algebraic Geometry Seminar \nSpeaker: Hamza Ahmed\, Northeastern University \nTitle: Heterotic Little String Theories and Inequivalent Genus-One Fibrations \nAbstract: Little String Theories (LSTs) are 6D Supersymmetric quantum field theories (SQFTs) with an additional physical relation called T-duality. This enables us to arrange them into equivalence classes\, where each equivalence class has 6D LSTs that lead to the same 5D effective theory when compactified on a circle. The problem of finding T-dual LSTs can be mapped to the problem of finding inequivalent genus-one fibrations of the same non-compact Calabi-Yau (CY) threefold. For T-dual theories\, certain field theory data is expected to match\, which then implies certain invariants of inequivalent fibrations. Focusing on theories with 8 supercharges (Heterotic LSTs)\, we use this geometry-field theory equivalence to study the T-duality landscape\, particularly in the case where the genus-one fiber does not have a section\, leading to what are called twisted T-dual theories. Based on the excellent agreement we find between the geometry and field theory arguments\, we conjecture the existence of a new class of twisted T-duals for which no geometric construction is known. \n  \n 
URL:https://cmsa.fas.harvard.edu/event/mathphys_102424/
LOCATION:Virtual
CATEGORIES:Mathematical Physics and Algebraic Geometry
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-Mathematical-Physics-and-Algebraic-Geometry-10.24.2024.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20240918T090000
DTEND;TZID=America/New_York:20240918T103000
DTSTAMP:20260618T133951
CREATED:20240904T181255Z
LAST-MODIFIED:20250328T150446Z
UID:10003442-1726650000-1726655400@cmsa.fas.harvard.edu
SUMMARY:CMSA/Tsinghua Math-Science Literature Lecture: Marc Lackenby
DESCRIPTION:CMSA/Tsinghua Math-Science Literature Lecture \nDate: Wednesday\, September 18\, 2024 \nTime: 9:00 – 10:30 am ET \nLocation: Via Zoom Webinar \nSpeaker: Marc Lackenby\, University of Oxford \nTitle: The complexity of knots \nAbstract: In his final paper in 1954\, Alan Turing wrote `No systematic method is yet known by which one can tell whether two knots are the same.’ Within the next 20 years\, Wolfgang Haken and Geoffrey Hemion had discovered such a method. However\, the computational complexity of this problem remains unknown. In my talk\, I will give a survey on this area\, that draws on the work of many low-dimensional topologists and geometers. Unfortunately\, the current upper bounds on the computational complexity of the knot equivalence problem remain quite poor. However\, there are some recent results indicating that\, perhaps\, knots are more tractable than they first seem. Specifically\, I will explain a theorem that provides\, for each knot type K\, a polynomial p_K with the property that any two diagrams of K with n_1 and n_2 crossings differ by at most p_K(n_1) + p_K(n_2) Reidemeister moves. \n\nBeginning in Spring 2020\, the CMSA began hosting a lecture series on literature in the mathematical sciences\, with a focus on significant developments in mathematics that have influenced the discipline\, and the lifetime accomplishments of significant scholars.
URL:https://cmsa.fas.harvard.edu/event/mathscilit2024_ml/
LOCATION:Virtual
CATEGORIES:Math Science Literature Lecture Series,Public Lecture,Special Lectures
ATTACH;FMTTYPE=image/jpeg:https://cmsa.fas.harvard.edu/media/Mathlit_Lackenby_8.5x11.jpg
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20240507T140000
DTEND;TZID=America/New_York:20240507T150000
DTSTAMP:20260618T133951
CREATED:20240411T181320Z
LAST-MODIFIED:20240819T151524Z
UID:10000835-1715090400-1715094000@cmsa.fas.harvard.edu
SUMMARY:Real-time observables in horizon thermodynamics
DESCRIPTION:General Relativity Seminar \nSpeaker: Albert Law\, Stanford \nTitle: Real-time observables in horizon thermodynamics \nAbstract: Euclidean black hole 1-loop determinants have recently been shown to compute a renormalized thermal canonical partition function for free fields in Lorentzian signature. A key ingredient is a ‘quasinormal mode (QNM) character’\, whose Fourier transform equals the renormalized spectral density of the single-particle Hamiltonian. Using a static patch in de Sitter space as an example\, in this talk\, I will offer new perspectives on the QNM character\, including its connection with the local density of states for the single-particle quantum mechanical problem associated with the Klein-Gordon equation\, and its direct relationships with (thermal) correlators of the free fields. I will discuss how these considerations might point toward a generalization to interacting theories.
URL:https://cmsa.fas.harvard.edu/event/general-relativity-seminar-5724/
LOCATION:Virtual
CATEGORIES:General Relativity Seminar
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-GR-Seminar-05.7.2024.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20240425T103000
DTEND;TZID=America/New_York:20240425T113000
DTSTAMP:20260618T133951
CREATED:20240416T133525Z
LAST-MODIFIED:20240422T185259Z
UID:10000888-1714041000-1714044600@cmsa.fas.harvard.edu
SUMMARY:The logarithmic double ramification locus
DESCRIPTION:Algebraic Geometry in String Theory Seminar \nSpeaker: Alessandro Chiodo\, IMJ-Paris Rive Gauche (Jussieu) \nTitle: The logarithmic double ramification locus \nAbstract: Given a family of smooth curves C -> S with a line bundle L on C\, it is natural to study the locus of points x in S where L_x is trivial on C_x. When the family is stable\, the definition can be extended\, not directly on the base scheme S\, but more naturally on a (logarithmic) blow-up S’ of S. The problem is in many ways analogue to the problem of defining a Néron model on the moduli space of stable curves (instead of a DVR). Over the past years\, David Holmes and his collaborators pioneered a new approach on a logarithmic modification of the entire moduli space of curves. In this talk\, we determine this logarithmic double ramification cycle and several variants and alternative presentations of it (work in collaboration with David Holmes).
URL:https://cmsa.fas.harvard.edu/event/agst-42524/
LOCATION:Virtual
CATEGORIES:Algebraic Geometry in String Theory Seminar
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-Algebraic-Geometry-in-String-Theory-04.25.2024.docx-2.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20240423T100000
DTEND;TZID=America/New_York:20240423T110000
DTSTAMP:20260618T133951
CREATED:20240415T162430Z
LAST-MODIFIED:20240422T154105Z
UID:10000833-1713866400-1713870000@cmsa.fas.harvard.edu
SUMMARY:Quantum Energy Inequalities
DESCRIPTION:General Relativity Seminar \nSpeaker: Chris Fewster\, York University \nTitle: Quantum Energy Inequalities \nAbstract: Many theorems of mathematical relativity\, including singularity and positive mass theorems\, include the classical energy conditions among their hypotheses. However\, matter described by quantum field theory can violate the classical energy conditions and indeed there is no lower bound to the energy density at a given point as the quantum state is varied. Do the classical theorems apply to quantised matter? \nIn this talk I discuss Quantum Energy Inequalities\, lower bounds on averages of the energy density along timelike curves or over spacetime regions\, that have been proved in QFT and are the remnants of the classical energy conditions after quantisation. I will also discuss some of their consequences.
URL:https://cmsa.fas.harvard.edu/event/general-relativity-seminar_42324/
LOCATION:Virtual
CATEGORIES:General Relativity Seminar
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20240416T110000
DTEND;TZID=America/New_York:20240416T120000
DTSTAMP:20260618T133951
CREATED:20240409T163938Z
LAST-MODIFIED:20240502T195940Z
UID:10000832-1713265200-1713268800@cmsa.fas.harvard.edu
SUMMARY:New Well-Posed Boundary Conditions for Semi-Classical Euclidean Gravity
DESCRIPTION:General Relativity Seminar \nSpeaker: Xiaoyi Liu\, UCSB \nTitle: New Well-Posed Boundary Conditions for Semi-Classical Euclidean Gravity \nAbstract: We consider four-dimensional Euclidean gravity in a finite cavity.  We point out that there exists a one-parameter family of boundary conditions\, parameterized by a real constant\, where a suitably Weyl-rescaled boundary metric is fixed\, and all give a well-posed elliptic system\, as opposed to the Dirichlet boundary condition. Focussing on static Euclidean solutions\, we derive a thermodynamic first law. Restricting to a spherical spatial boundary\, the infillings are flat space or the Schwarzschild solution and have similar thermodynamics to the Dirichlet case. We study the stability behavior of several geometries under these boundary conditions in both Euclidean and Lorentzian signatures and find two puzzles.
URL:https://cmsa.fas.harvard.edu/event/general-relativity-seminar_41624/
LOCATION:Virtual
CATEGORIES:General Relativity Seminar
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-GR-Seminar-04.16.2024.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20240322T090000
DTEND;TZID=America/New_York:20240322T103000
DTSTAMP:20260618T133951
CREATED:20240318T135251Z
LAST-MODIFIED:20240318T141920Z
UID:10001511-1711098000-1711103400@cmsa.fas.harvard.edu
SUMMARY:Non-Invertible Peccei-Quinn Symmetry and the Massless Quark Solution to the Strong CP Problem
DESCRIPTION:Quantum Matter in Mathematics and Physics Seminar \nSpeaker: Sungwoo Hong\, Korea Advanced Institute of Science and Technology (KAIST) \nTitle: Non-Invertible Peccei-Quinn Symmetry and the Massless Quark Solution to the Strong CP Problem \nAbstract: In this talk\, I will discuss a new solution to the strong CP problem\, one of the most important and challenging problems\, of the Standard Model (SM) based on the generalized global symmetry. To this end\, I will first show that there exist non-invertible chiral symmetries acting on quark fields once the SM is extended with gauged quark flavor symmetry. Interestingly enough\, such symmetries\, which we named them as “non-invertible Peccei-Quinn symmetries”\, exist only because the SM has the same number of generations as colors\, yet another feature that deserves a fundamental explanation. Then I discuss how these new generalized symmetries set the down Yukawa to be exactly zero and lead to a massless quark solution to the strong CP problem. Completion of the solution requires (i) generation of down quark Yukawas to be consistent with both observed quark mass spectrum and mixings and (ii) generation of O(1) CP violating phase called CKM phase\, crucially without destabilizing our solution to the strong CP problem. I will discuss that these rather non-trivial tasks can be achieved by a UV completion in an SU(9) quark color-flavor unification.
URL:https://cmsa.fas.harvard.edu/event/qm-32224/
LOCATION:Virtual
CATEGORIES:Quantum Matter
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-QMMP-03.22.2024.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20240320T140000
DTEND;TZID=America/New_York:20240320T150000
DTSTAMP:20260618T133951
CREATED:20240130T215041Z
LAST-MODIFIED:20240321T140550Z
UID:10001519-1710943200-1710946800@cmsa.fas.harvard.edu
SUMMARY:Solving olympiad geometry without human demonstrations
DESCRIPTION:New Technologies in Mathematics Seminar \nSpeaker: Trieu H. Trinh\, Google Deepmind and NYU Dept. of Computer Science \nTitle: Solving olympiad geometry without human demonstrations \nAbstract: Proving mathematical theorems at the olympiad level represents a notable milestone in human-level automated reasoning\, owing to their reputed difficulty among the world’s best talents in pre-university mathematics. Current machine-learning approaches\, however\, are not applicable to most mathematical domains owing to the high cost of translating human proofs into machine-verifiable format. The problem is even worse for geometry because of its unique translation challenges\, resulting in severe scarcity of training data. We propose AlphaGeometry\, a theorem prover for Euclidean plane geometry that sidesteps the need for human demonstrations by synthesizing millions of theorems and proofs across different levels of complexity. AlphaGeometry is a neuro-symbolic system that uses a neural language model\, trained from scratch on our large-scale synthetic data\, to guide a symbolic deduction engine through infinite branching points in challenging problems. On a test set of 30 latest olympiad-level problems\, AlphaGeometry solves 25\, outperforming the previous best method that only solves ten problems and approaching the performance of an average International Mathematical Olympiad (IMO) gold medallist. Notably\, AlphaGeometry produces human-readable proofs\, solves all geometry problems in the IMO 2000 and 2015 under human expert evaluation and discovers a generalized version of a translated IMO theorem in 2004. \n 
URL:https://cmsa.fas.harvard.edu/event/nt-32024/
LOCATION:Virtual
CATEGORIES:New Technologies in Mathematics Seminar
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-NTM-Seminar-03.20.2024.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20240315T100000
DTEND;TZID=America/New_York:20240315T113000
DTSTAMP:20260618T133951
CREATED:20240311T164549Z
LAST-MODIFIED:20240311T164549Z
UID:10002907-1710496800-1710502200@cmsa.fas.harvard.edu
SUMMARY:Monopoles\, scattering\, generalized symmetries
DESCRIPTION:Quantum Matter in Mathematics and Physics Seminar \nSpeaker: Diego Delmastro (Simons Center for Geometry and Physics) \nTitle: Monopoles\, scattering\, generalized symmetries\n \nAbstract: Gauge theory is a very mature subject by now. Surprisingly\, some of its symmetries have only been properly understood in the last couple of years. Specifically\, such theories typically have a very rich set of symmetries\, involving modern notions such as higher-form symmetries\, higher-group symmetries\, and categorical symmetries. A proper understanding of these generalized symmetries is not really crucial if we are interested in scattering processes involvingfundamental particles only\, but it does become quite essential if we want to add monopoles into the mix.  In this talk I will review where these generalized symmetries come from\, and how they impose constraints on scattering amplitudes of elementary particles against heavy monopoles. This will allow us to resolve a decades-old puzzle concerning such processes\, where incoming electrons appear to become fractional particles after the scattering event.
URL:https://cmsa.fas.harvard.edu/event/monopoles-scattering-generalized-symmetries/
LOCATION:Virtual
CATEGORIES:Quantum Matter
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/1710175391273-1be4453c-8fc6-4e08-84f5-51bec5d04ec1docx_1-2.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20240308T090000
DTEND;TZID=America/New_York:20240308T100000
DTSTAMP:20260618T133951
CREATED:20240305T204031Z
LAST-MODIFIED:20240307T165344Z
UID:10001510-1709888400-1709892000@cmsa.fas.harvard.edu
SUMMARY:A model for studying the sign problem on quantum computers: Z(3) gauge theory with three fermion flavors in 1+1 dimensions
DESCRIPTION:Quantum Matter in Mathematics and Physics Seminar \nSpeaker: Semeon Valgushev (Iowa State University) \nTitle: A model for studying the sign problem on quantum computers: Z(3) gauge theory with three fermion flavors in 1+1 dimensions \nAbstract: Many properties of quantum field theories can be understood with the help of classical numerical methods. Yet there are several outstanding problems — most remarkably the behaviour of nuclear matter at finite density and out-of-equilibrium real-time dynamics — that require the use of quantum algorithms. We present a simple yet physically rich toy model of QCD/nuclear matter at finite density\, termed “QZD”\, where Z stands for Z(3) gauge theory coupled to Nf = 3 fermion flavors\, suitable for simulation on near-term quantum devices. We study it using tensor networks and find that in weak coupling the spectrum is that of the expected mesons and baryons\, although the corrections in weak coupling are nontrivial. In strong coupling\, besides the usual baryon\, the singlet meson is a baryon anti-baryon state. For two special values of the coupling constant\, the lightest baryon is degenerate with the lightest octet meson\, and the lightest singlet meson\, respectively.
URL:https://cmsa.fas.harvard.edu/event/qm-3824/
LOCATION:Virtual
CATEGORIES:Quantum Matter
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/1709829554146-a2e594b2-ba0b-4248-bd23-63c7f0f9e199docx_1-1.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20240305T110000
DTEND;TZID=America/New_York:20240305T120000
DTSTAMP:20260618T133951
CREATED:20240229T165205Z
LAST-MODIFIED:20240813T154631Z
UID:10000827-1709636400-1709640000@cmsa.fas.harvard.edu
SUMMARY:High order WENO finite difference scheme  for Einstein-Yang-Mills equations
DESCRIPTION:General Relativity Seminar \nSpeaker: Yuewen Chen\, Tsinghua University \nTitle: High order WENO finite difference scheme  for Einstein-Yang-Mills equations \nAbstract: In this talk\, we will show the convergence analysis of the first-order finite difference scheme for static spherically symmetric $SU(2)$ Einstein-Yang-Mills (EYM) equations. We also construct a new WENO scheme for EYM.
URL:https://cmsa.fas.harvard.edu/event/general-relativity-seminar-3524/
LOCATION:Virtual
CATEGORIES:General Relativity Seminar
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-GR-Seminar-03.05.2024.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20240220T093000
DTEND;TZID=America/New_York:20240220T103000
DTSTAMP:20260618T133951
CREATED:20240219T195817Z
LAST-MODIFIED:20240219T195829Z
UID:10000825-1708421400-1708425000@cmsa.fas.harvard.edu
SUMMARY:Asymptotic decay for defocusing semilinear wave equations on Schwarzschild spacetimes
DESCRIPTION:General Relativity Seminar \nSpeaker: He Mei\, Shenzhen University \nTitle: Asymptotic decay for defocusing semilinear wave equations on Schwarzschild spacetimes \nAbstract: In this talk\, I will present a work on the long time dynamics of solutions to the defocusing semilinear wave equations on the Schwarzschild black hole spacetimes. For sufficiently smooth and localized initial data\, we show that the solution decays in the domain of outer communication. The proof relies on a vector field method of Dafermos-Rodnianski together with Strichartz estimates for linear waves by Marzuola-Metcalfe-Tataru-Tohaneanu.
URL:https://cmsa.fas.harvard.edu/event/general-relativity-seminar-22024/
LOCATION:Virtual
CATEGORIES:General Relativity Seminar
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20240207T090000
DTEND;TZID=America/New_York:20240207T103000
DTSTAMP:20260618T133951
CREATED:20240103T172620Z
LAST-MODIFIED:20241212T160057Z
UID:10001103-1707296400-1707301800@cmsa.fas.harvard.edu
SUMMARY:CMSA/Tsinghua Math-Science Literature Lecture: Amie Wilkinson
DESCRIPTION:CMSA/Tsinghua Math-Science Literature Lecture \nProf. Amie Wilkinson gave a lecture in the CMSA/Tsinghua Math-Science Literature Lecture Series. \nDate: Wednesday\, February 7\, 2024 \nTime: 9:00–10:30 am ET \nTitle: Stretching and shrinking: 85 years of the Hopf argument for ergodicity\nAbstract:  The early 20th century witnessed an explosion of activity\, much of it centered at Harvard\, on rigorizing the property of ergodicity first proposed by Boltzmann in his 1898  Ergodic Hypothesis for ideal gases. Earlier\, in the 1880’s\, Henri Poincaré and Felix Klein had also initiated a study of discrete groups of hyperbolic isometries. The geodesics in hyperbolic manifolds were discovered to carry a rich structure\, first investigated from a topological perspective by Emil Artin and Marston Morse.  The time was ripe to investigate geodesics in hyperbolic manifolds from an ergodic theoretic (i.e.\, statistical) perspective\, and indeed Gustav Hedlund proved in 1934 that the geodesic flow for closed hyperbolic surfaces is ergodic.\n\nIn 1939\, Eberhard Hopf published a proof of the ergodicity of geodesic flows for negatively curved surfaces containing a novel method\, now known as the Hopf argument.  The Hopf argument\, a “soft” argument for ergodicity of systems with some hyperbolicity (the “stretching and shrinking” in the title) has since seen wide application in geometry\, representation theory and dynamics.  I will discuss three results relying on the Hopf argument:\n\nTheorem (E. Hopf\, 1939\, D. Anosov\, 1967): In a closed manifold of negative sectional curvatures\, almost every geodesic is directionally equidistributed.\n\nTheorem (G. Mostow\, 1968) Let M and N be closed hyperbolic manifolds of dimension at least 3\, and let f:M->N be a homotopy equivalence.  Then f is homotopic to a unique isometry.\n\nTheorem (R. Mañé\, 1983\, A. Avila- S. Crovisier- A.W.\, 2022) The C^1 generic symplectomorphism of a closed symplectic manifold with positive entropy is ergodic.\n  \n\nBeginning in Spring 2020\, the CMSA began hosting a lecture series on literature in the mathematical sciences\, with a focus on significant developments in mathematics that have influenced the discipline\, and the lifetime accomplishments of significant scholars. \n 
URL:https://cmsa.fas.harvard.edu/event/mathscilit2024_aw/
LOCATION:Virtual
CATEGORIES:Event,Math Science Literature Lecture Series
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/Mathlit_Wilkinson_letter.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20240206T100000
DTEND;TZID=America/New_York:20240206T110000
DTSTAMP:20260618T133951
CREATED:20240202T170516Z
LAST-MODIFIED:20240209T200944Z
UID:10000823-1707213600-1707217200@cmsa.fas.harvard.edu
SUMMARY:Noncompact n-dimensional Einstein spaces as attractors for the Einstein flow
DESCRIPTION:General Relativity Seminar \nSpeaker: Jinhua Wang\, Xiamen University \nTitle: Noncompact n-dimensional Einstein spaces as attractors for the Einstein flow \nAbstract: We prove that along with the Einstein flow\, any small perturbations of an $n$($n\geq4$)-dimensional\, non-compact negative Einstein space with some “non-positive Weyl tensor” lead to a unique and global solution\, and the solution will be attracted to a noncompact Einstein space that is close to the background one. The $n=3$ case has been addressed by Wang-Yuan\, while in dimension $n\geq 4$\, as we know\, negative Einstein metrics in general have non-trivial moduli spaces. This fact is reflected on the structure of Einstein equations\, which further indicates no decay for the spatial Weyl tensor. Furthermore\, it is suggested in the proof that the mechanic preventing the metric from flowing back to the original Einstein metric lies in the non-decaying character of spatial Weyl tensor. In contrary to the compact case considered in Andersson-Moncrief\, our proof is independent of the theory of infinitesimal Einstein deformations. Instead\, we take advantage of the inherent geometric structures of Einstein equations and develop an approach of energy estimates for a hyperbolic system of Maxwell type. \nReferences – arXiv: 2209.15244\, 2309.15152\, 2311.00868
URL:https://cmsa.fas.harvard.edu/event/general-relativity-seminar-2624/
LOCATION:Virtual
CATEGORIES:General Relativity Seminar
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-GR-Seminar-02.06.2024.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20231215T100000
DTEND;TZID=America/New_York:20231215T113000
DTSTAMP:20260618T133951
CREATED:20240222T093357Z
LAST-MODIFIED:20240222T093357Z
UID:10002796-1702634400-1702639800@cmsa.fas.harvard.edu
SUMMARY:Exact lattice chiral symmetry in 2d gauge theory
DESCRIPTION:Quantum Matter Seminar \nSpeaker: Aleksey Cherman (UMN) \nTitle: Exact lattice chiral symmetry in 2d gauge theory \nAbstract: Preserving the symmetries of massless fermions is a well-known challenge in lattice field theory.  I’ll discuss symmetry-preserving lattice regularizations of 2d QED with one and two flavors of Dirac fermions\, as well as the `3450′ chiral gauge theory. The construction leverages bosonization and recently-proposed modifications of Villain-type lattice actions. The internal global symmetries act just as locally on the lattice as they do in the continuum\, the anomalies are reproduced at finite lattice spacing\, and in each case we’ve found a sign-problem-free dual formulation.
URL:https://cmsa.fas.harvard.edu/event/qm_121523/
LOCATION:Virtual
CATEGORIES:Quantum Matter
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-QMMP-12.15.23.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20231214T143000
DTEND;TZID=America/New_York:20231214T160000
DTSTAMP:20260618T133951
CREATED:20240109T001602Z
LAST-MODIFIED:20240109T001934Z
UID:10001133-1702564200-1702569600@cmsa.fas.harvard.edu
SUMMARY:When does a three-dimensions Chern-Simons theory have a time reversal symmetry?
DESCRIPTION:Speaker: Roman Geiko (UCLA) \nTitle: When does a three-dimensions Chern-Simons theory have a time reversal symmetry? \nIn this talk\, I will discuss the time reversal invariance of (spin-) Chern-Simons theory in 3 dimensions at both classical and quantum levels. I will show how to obtain a complete classification of Abelian anyons with the time reversal symmetry expressed in terms of the higher Gauss sums. Then\, I will comment on the time reversal symmetry of Chern-Simons in the non-Abelian case.
URL:https://cmsa.fas.harvard.edu/event/qm_121423/
LOCATION:Virtual
CATEGORIES:Quantum Matter
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-QMMP-12.14.2023.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20231205T110000
DTEND;TZID=America/New_York:20231205T120000
DTSTAMP:20260618T133951
CREATED:20240226T112803Z
LAST-MODIFIED:20240813T160712Z
UID:10002870-1701774000-1701777600@cmsa.fas.harvard.edu
SUMMARY:The Feynman propagator and self-adjointness
DESCRIPTION:General Relativity Seminar \nSpeaker: Andras Vasy (Stanford) \nTitle: The Feynman propagator and self-adjointness \nAbstract: In this talk I will discuss the Feynman and anti-Feynman inverses for wave operators on certain Lorentzian manifolds; these are two inverses which from a microlocal analysis perspective are more natural than the standard causal (advanced/retarded) ones. For instance\, for the spectral family of the wave operator\, these are the natural inverses when the spectral parameter is non-real. Indeed\, I will explain that these connect to the self-adjointness of the wave operator\, and the positivity properties that follow. \n 
URL:https://cmsa.fas.harvard.edu/event/gr_12523/
LOCATION:Virtual
CATEGORIES:General Relativity Seminar
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-GR-Seminar-12.05.2023.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20231120T090000
DTEND;TZID=America/New_York:20231120T103000
DTSTAMP:20260618T133951
CREATED:20240108T175825Z
LAST-MODIFIED:20240222T055339Z
UID:10001130-1700470800-1700476200@cmsa.fas.harvard.edu
SUMMARY:CMSA/Tsinghua Math-Science Literature Lecture: Scott Kominers
DESCRIPTION:CMSA/Tsinghua Math-Science Literature Lecture \n \nProf. Scott Kominers will present a lecture in the CMSA/Tsinghua Math-Science Literature Lecture Series. \nDate: Monday\, November 20\, 2023 \nTime: 9:00 – 10:30 am ET \nLocation: Via Zoom Webinar \nTitle: 60 Years of Matching: From Gale and Shapley to Trading Networks \nAbstract: Gale and Shapley’s 1962 American Mathematical Monthly paper\, “College Admissions and the Stability of Marriage\,” is by now one of the most cited articles in the journal’s history\, having served as the foundation for an entire branch of the field of market design. This success owes in large part to the beautiful\, applicable\, and surprisingly general theory of matching mechanisms uncovered in Gale and Shapley’s work. This talk traces the history and evolution of matching theory from that paper forward to the present day\, along the way touching on real-world applications to everything from medical residency matching to electricity markets. \nModerator: Sergiy Verstyuk \n\nBeginning in Spring 2020\, the CMSA began hosting a lecture series on literature in the mathematical sciences\, with a focus on significant developments in mathematics that have influenced the discipline\, and the lifetime accomplishments of significant scholars. \n  \nCMSA COVID-19 Policies
URL:https://cmsa.fas.harvard.edu/event/mathscilit2023/
LOCATION:Virtual
CATEGORIES:Event,Math Science Literature Lecture Series
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/Mathlit_Kominers_8.5x11.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20231115T103000
DTEND;TZID=America/New_York:20231115T113000
DTSTAMP:20260618T133951
CREATED:20240222T105852Z
LAST-MODIFIED:20240222T105913Z
UID:10002803-1700044200-1700047800@cmsa.fas.harvard.edu
SUMMARY:A bulk gap in the presence of edge states for a truncated Haldane pseudopotential
DESCRIPTION:Topological Quantum Matter Seminar \nSpeaker: Amanda Young\, UIUC \nTitle: A bulk gap in the presence of edge states for a truncated Haldane pseudopotential \nAbstract: Haldane pseudopotentials were first introduced as Hamiltonian models for the fractional quantum Hall effect\, and it has been long expected that they should exhibit the characteristic properties of this exotic phase of matter\, including a spectral gap above the ground state energy. We will discuss recent work that verified this gap conjecture for a truncated version of the 1/3-filled Haldane pseudopotential in the cylinder geometry. Numerical evidence suggested that for open boundary conditions the gap of the truncated model closes as the cylinder radius converges to zero and that this closure is due to the presence of edge modes; in contrast\, for periodic boundary conditions\, the gap remains robustly order one in the same radius limit. The standard scheme for applying spectral gap estimating techniques to the model with periodic boundary conditions\, though\, produces a lower bound on the bulk gap that still reflects the energy of the edge modes. To obtain an estimate on the bulk gap that reflects its true behavior\, a new gap estimating strategy was developed. By customizing the spectral gap method to key invariant subspaces of the Hamiltonian\, we are able to successfully avoid the edge states and produce a more accurate lower bound on the bulk gap. In this talk\, we discuss this invariant subspace strategy for proving bulk gaps in the presence of edge states. This is based off joint work with S. Warzel. \n  \n 
URL:https://cmsa.fas.harvard.edu/event/tqms_111523/
LOCATION:Virtual
CATEGORIES:Topological Quantum Matter Seminar
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-Topological-Seminar-11.15.23.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20231114T110000
DTEND;TZID=America/New_York:20231114T120000
DTSTAMP:20260618T133951
CREATED:20240223T052212Z
LAST-MODIFIED:20240223T052212Z
UID:10002814-1699959600-1699963200@cmsa.fas.harvard.edu
SUMMARY:Quasi-Local Mass in a Binary Black Hole Merger
DESCRIPTION:General Relativity Seminar \nSpeaker: Daniel Kolb (Max Planck Institute) \nTitle: Quasi-Local Mass in a Binary Black Hole Merger \nAbstract: One of the major open problems in classical general relativity is how one should define the mass of a finite region of space. In this talk\, we will investigate a promising definition proposed by Wang and Yau in 2009. A closed 2-surface bounding the region of interest is embedded isometrically into Minkowski space. The mass is then calculated by comparing the extrinsic geometries. The Wang-Yau mass has many desirable properties\, but it has previously not been calculated for surfaces in dynamical spacetimes. To remedy this\, we will discuss how the Wang-Yau mass can be computed in practice and extend the definition to surfaces important in black hole dynamics: their quasi-local horizons. Finally\, we look at how this mass behaves in a merger of black holes.
URL:https://cmsa.fas.harvard.edu/event/gr_111423/
LOCATION:Virtual
CATEGORIES:General Relativity Seminar
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20231108T153000
DTEND;TZID=America/New_York:20231108T163000
DTSTAMP:20260618T133951
CREATED:20240222T113928Z
LAST-MODIFIED:20240222T113941Z
UID:10002810-1699457400-1699461000@cmsa.fas.harvard.edu
SUMMARY:Fitting ellipsoids to random points
DESCRIPTION:Probability Seminar \nSpeaker: Antoine Maillard (ETH Zürich) \nTitle: Fitting ellipsoids to random points \nAbstract: We consider the problem of exactly fitting an ellipsoid (centered at 0) to n standard Gaussian random vectors in dimension d\, for very large n and d. This problem has connections to questions in statistical learning and theoretical computer science\, and is conjectured to undergo a sharp transition: with high probability\, it has a solution if n < d^2/4\, while it is not satisfiable if n > d^2/4. In this talk we will discuss the origin of this conjecture\, and highlight some recent progress\, in three different directions: \n\nA proof that the problem is feasible for n < d^2 / C\, for some (large) constant C\, significantly improving over previously-known bounds.\nA non-rigorous characterization of the conjecture\, as well as significant generalizations\, using analytical methods of statistical physics.\nA rigorous proof of a satisfiability transition exactly at n = d^2 / 4 in a slightly relaxed version of the problem\, the first rigorous result characterizing the expected phase transition in ellipsoid fitting. The proof is inspired by the non-rigorous characterization discussed above.\n\nThis talk is based on the three manuscripts: arXiv:2307.01181\, arXiv:2310.01169\, arXiv:2310.05787\, which are joint works with A. Bandeira\, Tim Kunisky\, Shahar Mendelson and Elliot Paquette.
URL:https://cmsa.fas.harvard.edu/event/probability-11823/
LOCATION:Virtual
CATEGORIES:Probability Seminar
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20231101T103000
DTEND;TZID=America/New_York:20231101T113000
DTSTAMP:20260618T133951
CREATED:20240222T111415Z
LAST-MODIFIED:20240222T111747Z
UID:10002806-1698834600-1698838200@cmsa.fas.harvard.edu
SUMMARY:Unveiling Correlated Topological Insulators through Fermionic Tensor Network States
DESCRIPTION:Topological Quantum Matter Seminar \nSpeaker: Shenghan Jiang\, Kavli Institute for Theoretical Sciences UCAS \nTitle: Unveiling Correlated Topological Insulators through Fermionic Tensor Network States \nAbstract: The study of topological band insulators has revealed fascinating phases characterized by band topology indices\, harboring extraordinary boundary modes protected by anomalous symmetry actions. In strongly correlated systems\, it has been established that topological insulator phases persist as stable phases. However\, due to the inability to express the ground states of such systems as Slater determinants\, the formulation of generic variational wavefunctions for numerical simulations is highly desirable.\nIn this talk\, we tackle this challenge by developing a comprehensive framework with fermionic tensor network states. Starting from simple assumptions\, we write down tensor equations\, construct edge theories and extract quantum anomaly data for topological insulators. By exhaustively exploring all possible sets of equations\, we achieve a systematic classification of topological insulator phases. Imposing the solutions of a given set of equations onto local tensors\, we obtain generic variational wavefunctions for corresponding topological insulator phases. Our methodology provides a crucial first step towards simulating topological insulators in strongly correlated systems. \n 
URL:https://cmsa.fas.harvard.edu/event/tqms_11123/
LOCATION:Virtual
CATEGORIES:Topological Quantum Matter Seminar
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-Topological-Seminar-11.01.23.docx-1.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20231025T153000
DTEND;TZID=America/New_York:20231025T163000
DTSTAMP:20260618T133951
CREATED:20240223T055628Z
LAST-MODIFIED:20240223T055719Z
UID:10002822-1698247800-1698251400@cmsa.fas.harvard.edu
SUMMARY:Tail estimates for stationary KPZ models
DESCRIPTION:Probability Seminar \nSpeaker: Benjamin Landon (University of Toronto) \nTitle: Tail estimates for stationary KPZ models \nAbstract: The limiting distributions of the KPZ universality class exhibit tail exponents of 3/2 and 3. In this talk we will review recent work studying the upper tail exponent 3/2 in the moderate deviations regime of several KPZ models at finite size\, including the stochastic six vertex model\, the ASEP and a class of non-integrable interacting diffusions. \nJoint work with Christian Noack and Phil Sosoe. \n 
URL:https://cmsa.fas.harvard.edu/event/probability-102523/
LOCATION:Virtual
CATEGORIES:Probability Seminar
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-Probability-Seminar-10.25.23.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20230920T140000
DTEND;TZID=America/New_York:20230920T150000
DTSTAMP:20260618T133951
CREATED:20240227T083355Z
LAST-MODIFIED:20240227T083355Z
UID:10002873-1695218400-1695222000@cmsa.fas.harvard.edu
SUMMARY:The TinyStories Dataset: How Small Can Language Models Be And Still Speak Coherent
DESCRIPTION:New Technologies in Mathematics Seminar \nSpeaker: Ronen Eldan\, Microsoft Research \nTitle: The TinyStories Dataset: How Small Can Language Models Be And Still Speak Coherent \nAbstract: While generative language models exhibit powerful capabilities at large scale\, when either the model or the number of training steps is too small\, they struggle to produce coherent and fluent text: Existing models whose size is below a few billion parameters often do not generate coherent text beyond a few sentences. Hypothesizing that one of the main reasons for the strong reliance on size is the vast breadth and abundance of patterns in the datasets used to train those models\, this motivates the following question: Can we design a dataset that preserves the essential elements of natural language\, such as grammar\, vocabulary\, facts\, and reasoning\, but that is much smaller and more refined in terms of its breadth and diversity? \nIn this talk\, we introduce TinyStories\, a synthetic dataset of short stories that only contain words that 3 to 4-year-olds typically understand\, generated by GPT-3.5/4. We show that TinyStories can be used to train and analyze language models that are much smaller than the state-of-the-art models (below 10 million parameters)\, or have much simpler architectures (with only one transformer block)\, yet still produce fluent and consistent stories with several paragraphs that are diverse and have almost perfect grammar\, and demonstrate certain reasoning capabilities. We also show that the trained models are substantially more interpretable than larger ones\, as we can visualize and analyze the attention and activation patterns of the models\, and show how they relate to the generation process and the story content. We hope that TinyStories can facilitate the development\, analysis and research of language models\, especially for low-resource or specialized domains\, and shed light on the emergence of language capabilities in LMs. \n 
URL:https://cmsa.fas.harvard.edu/event/nt-92023/
LOCATION:Virtual
CATEGORIES:New Technologies in Mathematics Seminar
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-NTM-Seminar-09.20.2023.png
END:VEVENT
BEGIN:VEVENT
DTSTART;TZID=America/New_York:20230824T100000
DTEND;TZID=America/New_York:20230824T113000
DTSTAMP:20260618T133951
CREATED:20230904T055455Z
LAST-MODIFIED:20240227T085359Z
UID:10001126-1692871200-1692876600@cmsa.fas.harvard.edu
SUMMARY:Two of my favorite numbers: 8 and 24
DESCRIPTION:Quantum Matter Seminar \nSpeaker: John Baez (University of California\, Riverside) \nTitle: Two of my favorite numbers: 8 and 24 \nAbstract: The numbers 8 and 24 play special roles in mathematics. The number 8 is special because of Bott periodicity\, the octonions and the E8 lattice\, while 24 is special for many reasons\, including the binary tetrahedral group\, the 3rd stable homotopy group of spheres\, and the Leech lattice. The number 8 does for superstring theory what the number 24 does for bosonic string theory. In this talk\, which is intended to be entertaining\, I will overview these matters and also some connections between the numbers 8 and 24.
URL:https://cmsa.fas.harvard.edu/event/qm_82423/
LOCATION:Virtual
CATEGORIES:Quantum Matter
ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-QMMP-08.24.23.png
END:VEVENT
END:VCALENDAR