BEGIN:VCALENDAR VERSION:2.0 PRODID:-//CMSA - ECPv6.15.18//NONSGML v1.0//EN CALSCALE:GREGORIAN METHOD:PUBLISH X-WR-CALNAME:CMSA 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 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 END:VTIMEZONE BEGIN:VEVENT DTSTART;TZID=America/New_York:20231108T140000 DTEND;TZID=America/New_York:20231108T150000 DTSTAMP:20260503T163824 CREATED:20240222T095919Z LAST-MODIFIED:20240222T095919Z UID:10002798-1699452000-1699455600@cmsa.fas.harvard.edu SUMMARY:Peano: Learning Formal Mathematical Reasoning Without Human Data DESCRIPTION:New Technologies in Mathematics Seminar \nSpeaker: Gabriel Poesia\, Dept. of Computer Science\, Stanford University \nTitle: Peano: Learning Formal Mathematical Reasoning Without Human Data \nAbstract: Peano is a theorem proving environment in which a computational agent can start tabula rasa in a new domain\, learn to solve problems through curiosity-driven exploration\, and create its own higher level actions. Gabriel will describe the system\, present case studies on learning to solve simple algebra problems from the Khan Academy platform\, and describe work on progress on learning the Natural Number Game\, a popular introduction to theorem proving in Lean for mathematicians. \n  URL:https://cmsa.fas.harvard.edu/event/nt-11823/ LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States CATEGORIES:New Technologies in Mathematics Seminar ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/NTM-11.08.2023.png END:VEVENT BEGIN:VEVENT DTSTART;TZID=America/New_York:20231108T153000 DTEND;TZID=America/New_York:20231108T163000 DTSTAMP:20260503T163824 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:20231109T130000 DTEND;TZID=America/New_York:20231109T140000 DTSTAMP:20260503T163824 CREATED:20240223T060824Z LAST-MODIFIED:20240223T060824Z UID:10002824-1699534800-1699538400@cmsa.fas.harvard.edu SUMMARY:Nuclear chromodynamics: non-equilibrium phase transition in the nucleus of a living cell DESCRIPTION:Active Matter Seminar\n\n\nSpeaker: Alexander Grosberg (NYU)\n\nTitle: Nuclear chromodynamics: non-equilibrium phase transition in the nucleus of a living cell \nAbstract: Nucleus of a living cell houses a cell genome – a polymer called chromatin\, which is a functional form of DNA.  It is very long\, e.g.\, 2 meters long for every human cell.  Nucleus is also an arena of incessant energy-driven activity.  Experiments show that chromatin undergoes large scale motions sustained over long times of order seconds.  In the talk\, after reviewing the phenomenology\, I will show how these flows may arise due to a phase transition in which chromatin-driving motors\, such as RNA polymerase\, form a polar (“ferromagnetic”) order controlled by hydrodynamic interactions.  The talk is based on the joint work with I.Eshghi and A.Zidovska. URL:https://cmsa.fas.harvard.edu/event/am-11923/ LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States CATEGORIES:Active Matter Seminar ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-Active-Matter-Seminar-11.09.23.png END:VEVENT BEGIN:VEVENT DTSTART;TZID=America/New_York:20231109T163000 DTEND;TZID=America/New_York:20231109T173000 DTSTAMP:20260503T163824 CREATED:20240222T110254Z LAST-MODIFIED:20240222T110327Z UID:10002805-1699547400-1699551000@cmsa.fas.harvard.edu SUMMARY:Uniqueness of Landau levels and their analogs with higher Chern numbers DESCRIPTION:Topological Quantum Matter Seminar \nSpeaker: Bruno Mera\, Instituto Superior Tecnico \nTitle: Uniqueness of Landau levels and their analogs with higher Chern numbers \nAbstract: Lowest Landau level wavefunctions are eigenstates of the Hamiltonian of a charged par- ticle in two dimensions under a uniform magnetic field. They are known to be holomorphic both in real and momentum spaces\, and also exhibit uniform\, translationally invariant\, geometrical properties in momentum space. In this talk\, using the Stone-von Neumann the- orem\, we show that lowest Landau level wavefunctions are indeed the only possible states with unit Chern number satisfying these conditions. We also prove the uniqueness of their direct analogs with higher Chern numbers and provide their expressions. \nRef: Bruno Mera and Tomoki Ozawa. Uniqueness of Landau levels and their analogs with higher Chern numbers. arXiv:2304.00866\, 2023. arXiv:2304.00866. \n  URL:https://cmsa.fas.harvard.edu/event/tqms_11823/ LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States CATEGORIES:Topological Quantum Matter Seminar ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-Topological-Seminar-11.09.23.png END:VEVENT BEGIN:VEVENT DTSTART;TZID=America/New_York:20231113T103000 DTEND;TZID=America/New_York:20231113T113000 DTSTAMP:20260503T163824 CREATED:20240222T070558Z LAST-MODIFIED:20240222T070558Z UID:10002787-1699871400-1699875000@cmsa.fas.harvard.edu SUMMARY:Stacky small resolutions of determinantal octic double solids and noncommutative Gopakumar-Vafa invariants DESCRIPTION:Algebraic Geometry in String Theory Seminar \n\nSpeaker: Sheldon Katz\, UIUC \nTitle: Stacky small resolutions of determinantal octic double solids and noncommutative Gopakumar-Vafa invariants \nAbstract:  A determinantal octic double solid is the double cover X of P^3 branched along the degree 8 determinant of a symmetric matrix of homogeneous forms on P^3.  These X are nodal CY threefolds which do not admit a projective small resolution.  B-model techniques can be applied to compute GV invariants up to g \le 32.  This raises the question: what is the geometric meaning of these invariants? \nEvidence suggests that these enumerative invariants are associated with moduli stacks of coherent sheaves of modules over a sheaf B of noncommutative algebras on X constructed by Kuznetsov.  One of these moduli stacks is a stacky small resolution X’ of X itself.  This leads to another geometric interpretation of the invariants as being associated with moduli of sheaves on X’ twisted by a Brauer class.  Geometric computations based on these working definitions always agree with the B-model computations. \nThis talk is based on joint work with Albrecht Klemm\, Thorsten Schimannek\, and Eric Sharpe. \n\n  URL:https://cmsa.fas.harvard.edu/event/agst-111323/ LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States CATEGORIES:Algebraic Geometry in String Theory Seminar ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-Algebraic-Geometry-in-String-Theory-11.13.2023.png END:VEVENT BEGIN:VEVENT DTSTART;TZID=America/New_York:20231113T163000 DTEND;TZID=America/New_York:20231113T173000 DTSTAMP:20260503T163824 CREATED:20240223T081522Z LAST-MODIFIED:20240223T081522Z UID:10002834-1699893000-1699896600@cmsa.fas.harvard.edu SUMMARY:Koszul duality in QFT DESCRIPTION:Speaker: Brian Williams (Boston University) \nTitle: Koszul duality in QFT \nAbstract: We will describe appearances of the algebraic phenomena of Koszul duality in the context of boundary conditions and defects in quantum field theory. Primarily motivated by topological string theory\, this point of view was pioneered by Costello and Li in their proposal for a twisted version of the AdS/CFT correspondence. Since then\, many important examples of (twisted) holographic dualities in string and M-theory have been studied in work of Costello\, Gaiotto\, Paquette and many others. I will survey some of these examples and some current work with Raghavendran and Saberi which uses this formalism to predict exceptional symmetries present in M-theory. \n  URL:https://cmsa.fas.harvard.edu/event/colloquium-111323/ LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States CATEGORIES:Colloquium ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-Colloquium-11.13.2023.png END:VEVENT BEGIN:VEVENT DTSTART;TZID=America/New_York:20231114T110000 DTEND;TZID=America/New_York:20231114T120000 DTSTAMP:20260503T163824 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:20231115T103000 DTEND;TZID=America/New_York:20231115T113000 DTSTAMP:20260503T163824 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:20231115T140000 DTEND;TZID=America/New_York:20231115T150000 DTSTAMP:20260503T163824 CREATED:20240222T094758Z LAST-MODIFIED:20240222T095355Z UID:10002797-1700056800-1700060400@cmsa.fas.harvard.edu SUMMARY:On the Power of Forward pass through Transformer Architectures DESCRIPTION:New Technologies in Mathematics Seminar \nSpeaker: Abhishek Panigrahi\, Dept. of Computer Science\, Princeton University \nTitle: On the Power of Forward pass through Transformer Architectures \nAbstract: Highly trained transformers are capable of interesting computations as they infer for an input. The exact mechanism that these models use during forward passes is an interesting area of study. This talk studies two interesting phenomena. \nIn the first half\, we explore how and why pre-trained language models\, specifically BERT of moderate sizes\, can effectively learn linguistic structures like parse trees during pre-training. Specifically\, using synthetic data through PCFGs\, we show how moderate-sized transformers can perform forward-backward parsing\, also known as the inside-outside algorithm\, during inference. We further understand the role of the pre-training loss for the model to learn to parse during pre-training. \nIn the second half\, we consider in-context learning of large language models\, where they learn to reason on the fly. An ongoing hypothesis is that transformers simulate gradient descent at inference to perform in-context learning. We propose the Transformer in Transformer (TinT) framework\, which creates explicit transformer architectures that can simulate and fine-tune a small pre-trained transformer model during inference. E.g. a 1.3B parameter TINT model can simulate and fine-tune a 125 million parameter model in a single forward pass. This framework suggests that large transformers might execute intricate sub-routines during inference\, and provides insights for enhancing their capabilities through intelligent design considerations. \n  URL:https://cmsa.fas.harvard.edu/event/nt-111523/ LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States CATEGORIES:New Technologies in Mathematics Seminar ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/NTM-11.15.2023.png END:VEVENT BEGIN:VEVENT DTSTART;TZID=America/New_York:20231115T153000 DTEND;TZID=America/New_York:20231115T163000 DTSTAMP:20260503T163824 CREATED:20240223T053940Z LAST-MODIFIED:20240223T054457Z UID:10002818-1700062200-1700065800@cmsa.fas.harvard.edu SUMMARY:Thresholds DESCRIPTION:Probability Seminar \nSpeaker: Jinyoung Park (NYU) \nTitle: Thresholds \nAbstract: For a finite set X\, a family F of subsets of X is said to be increasing if any set A that contains B in F is also in F. The p-biased product measure of F increases as p increases from 0 to 1\, and often exhibits a drastic change around a specific value\, which is called a “threshold.” Thresholds of increasing families have been of great historical interest and a central focus of the study of random discrete structures (e.g. random graphs and hypergraphs)\, with estimation of thresholds for specific properties the subject of some of the most challenging work in the area. In 2006\, Jeff Kahn and Gil Kalai conjectured that a natural (and often easy to calculate) lower bound q(F) (which we refer to as the “expectation-threshold”) for the threshold is in fact never far from its actual value. A positive answer to this conjecture enables one to narrow down the location of thresholds for any increasing properties in a tiny window. In particular\, this easily implies several previously very difficult results in probabilistic combinatorics such as thresholds for perfect hypergraph matchings (Johansson–Kahn–Vu) and bounded-degree spanning trees (Montgomery). I will present recent progress on this topic. Based on joint work with Keith Frankston\, Jeff Kahn\, Bhargav Narayanan\, and Huy Tuan Pham. URL:https://cmsa.fas.harvard.edu/event/probability-111523/ LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States CATEGORIES:Probability Seminar ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-Probability-Seminar-11.15.23.png END:VEVENT BEGIN:VEVENT DTSTART;TZID=America/New_York:20231117T120000 DTEND;TZID=America/New_York:20231117T130000 DTSTAMP:20260503T163824 CREATED:20240227T113236Z LAST-MODIFIED:20240227T113251Z UID:10002879-1700222400-1700226000@cmsa.fas.harvard.edu SUMMARY:A quasi-local mass in general relativity DESCRIPTION:Member Seminar \nSpeaker: Aghil Alaee \nTitle: A quasi-local mass in general relativity \nAbstract: One of the fundamental open problems in geometric analysis and mathematical relativity is constructing a (universal) energy/mass quantity to compute the energy/mass of a finite region of spacetime\, which can include a star\, black hole\, or galaxy. We define a new gauge-independent quasi-local mass and energy with respect to the Minkowski spacetime\, and show its relation to the Brown-York Hamilton-Jacobi analysis. A quasi-local proof of the positivity\, based on spacetime harmonic functions\, is given for admissible closed spacelike 2-surfaces which enclose an initial data set satisfying the dominant energy condition.  Rigidity is also established in that vanishing energy implies that the 2-surface arises from an embedding into Minkowski space\, and conversely\, the mass vanishes for any such surface. This is joint work with M. Khuri and S.T. Yau. \n  URL:https://cmsa.fas.harvard.edu/event/member-seminar-111723/ LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States CATEGORIES:Member Seminar END:VEVENT BEGIN:VEVENT DTSTART;TZID=America/New_York:20231120T090000 DTEND;TZID=America/New_York:20231120T103000 DTSTAMP:20260503T163824 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:20231120T140000 DTEND;TZID=America/New_York:20231120T150000 DTSTAMP:20260503T163824 CREATED:20240222T103744Z LAST-MODIFIED:20240222T105558Z UID:10002800-1700488800-1700492400@cmsa.fas.harvard.edu SUMMARY:Emergent composite-fermion Luttinger liquid at the half-filled Landau level DESCRIPTION:Topological Quantum Matter Seminar \nSpeaker: Prashant Kumar\, University of Chicago \nTitle: Emergent composite-fermion Luttinger liquid at the half-filled Landau level \nAbstract: The half-filled Landau level is a fascinating point in the phase diagram of quantum Hall effect that has been hypothesized to be a non-Fermi liquid where composite-fermions (CFs) emerge at low energies. In this talk\, I will present our numerical calculations of the excitation spectrum of this state on infinite cylinders. By comparing our results with a quasi-1D theory of CFs\, we show compelling quantitative evidence for the emergence of a Luttinger liquid of composite-fermions at low energies\, distinct from that of electrons. I will comment on some future directions. URL:https://cmsa.fas.harvard.edu/event/tqms_112023/ LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States CATEGORIES:Topological Quantum Matter Seminar ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-Topological-Seminar-11.20.23-1.png END:VEVENT BEGIN:VEVENT DTSTART;TZID=America/New_York:20231120T163000 DTEND;TZID=America/New_York:20231120T173000 DTSTAMP:20260503T163824 CREATED:20240223T080617Z LAST-MODIFIED:20240223T080617Z UID:10002833-1700497800-1700501400@cmsa.fas.harvard.edu SUMMARY:The analytical challenges of connectomics DESCRIPTION:Speaker: Jeff W. Lichtman (Harvard University) \nTitle: The analytical challenges of connectomics \nAbstract: Recent progress in generating synapse-level maps of brains\, a field known as connectomics\, brings both opportunities and challenges. The upside is that the biophysical instantiation of memories\, behaviors\, and knowledge will soon be before us. The downside is that no one knows exactly how to make sense of this data. I will show what connectomics data sets are and attempt to explain why it is so difficult to unravel their meaning. URL:https://cmsa.fas.harvard.edu/event/colloquium-112023/ LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States CATEGORIES:Colloquium ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-Colloquium-11.20.2023.png END:VEVENT BEGIN:VEVENT DTSTART;TZID=America/New_York:20231122T160000 DTEND;TZID=America/New_York:20231122T173000 DTSTAMP:20260503T163824 CREATED:20240221T102006Z LAST-MODIFIED:20240221T102032Z UID:10002775-1700668800-1700674200@cmsa.fas.harvard.edu SUMMARY:Modulated Gauge Theories and Fracton Behavior in 2D DESCRIPTION:Quantum Matter Seminar \nSpeaker: Guilherme Delfino Silva (Boston University) \nTitle: Modulated Gauge Theories and Fracton Behavior in 2D \nAbstract: In this talk we investigate deconfined phases of two-dimensional ZN lattice gauge theories associated to spatially modulated symmetries. In order to study the low-energy physics of such modulated gauge theories we propose and explore exactly solvable gapped Hamiltonians\, which allow us to fully characterize their low-energy properties at zero temperature. We provide explicit examples and discuss how non-polynomial symmetries\, as exponential symmetries\, are powerful enough to fully constrain the mobility of isolated excitations. URL:https://cmsa.fas.harvard.edu/event/qm_112223/ LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States CATEGORIES:Quantum Matter ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-QMMP-11.22.2023..png END:VEVENT BEGIN:VEVENT DTSTART;TZID=America/New_York:20231127T103000 DTEND;TZID=America/New_York:20231127T113000 DTSTAMP:20260503T163824 CREATED:20240221T113319Z LAST-MODIFIED:20240221T113411Z UID:10002783-1701081000-1701084600@cmsa.fas.harvard.edu SUMMARY:A p-adic Laplacian on the Tate curve DESCRIPTION:Algebraic Geometry in String Theory Seminar \nSpeaker: An Huang (Brandeis) \nPre-talk Speaker: TBA: 10:00-10:30 am \n\n\nTitle: A p-adic Laplacian on the Tate curve \nAbstract: We shall first explain the relation between a family of deformations of genus zero p-adic string worldsheet action and Tate’s thesis. We then propose a genus one p-adic string worldsheet action. The key is the definition of a p-adic Laplacian operator on the Tate curve. We show that the genus one p-adic Green’s function exists\, is unique under some obvious constraints\, is locally constant off diagonal\, and has a reflection symmetry. It can also be numerically computed exactly off the diagonal\, thanks to some simplifications due to the p-adic setup. Numerics suggest that at least in some special cases\, the asymptotic behavior of the Green’s function near the diagonal is a direct p-adic counterpart of the familiar Archimedean case\, although the p-adic Laplacian is not a local operator. Joint work in progress with Rebecca Rohrlich. URL:https://cmsa.fas.harvard.edu/event/agst-112723/ LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States CATEGORIES:Algebraic Geometry in String Theory Seminar ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-Algebraic-Geometry-in-String-Theory-11.27.2023.png END:VEVENT BEGIN:VEVENT DTSTART;TZID=America/New_York:20231127T163000 DTEND;TZID=America/New_York:20231127T173000 DTSTAMP:20260503T163824 CREATED:20240223T080018Z LAST-MODIFIED:20240223T080018Z UID:10002831-1701102600-1701106200@cmsa.fas.harvard.edu SUMMARY:What do topological dynamics\, combinatorics\, and model theory have in common? DESCRIPTION:Speaker: Dana Bartosova (University of Florida) \nTitle: What do topological dynamics\, combinatorics\, and model theory have in common? \nAbstract: A striking correspondence between dynamics of automorphism groups of countable first order structures and Ramsey theory of finitary approximation of the structures was established in 2005 by Kechris\, Pestov\, and Todocevic. Since then\, their work has been generalized and applied in many directions. It also struck a fresh wave of interest in finite Ramsey theory.  Many classes of finite structures are shown to have the Ramsey property by encoding their problem in a known Ramsey class and translating a solution back. This is often a case-by-case approach and naturally there is a great need for abstracting the process. There has been much success on this front\, however\, none of the tools captures every situation. We will discuss one such encoding via a model-theoretic notion of semi-retraction introduced by Lynn Scow in 2012. In a joint work\, we showed that a semi-retraction transfers the Ramsey property from one class of structures to another under quite general conditions. We compare semi-retractions to a category-theoretical notion of pre-adjunction revived by Mašulović in 2016. If time permits\, I will mention a transfer theorem of the Ramsey property from a class of finite structures to their uncountable ultraproducts\, which is an AIMSQuaRE project with Džamonja\, Patel\, and Scow. URL:https://cmsa.fas.harvard.edu/event/colloquium-112723/ LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States CATEGORIES:Colloquium ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-Colloquium-11.27.2023_Page_1.png END:VEVENT BEGIN:VEVENT DTSTART;TZID=America/New_York:20231128T110000 DTEND;TZID=America/New_York:20231128T120000 DTSTAMP:20260503T163824 CREATED:20240223T051146Z LAST-MODIFIED:20240223T051146Z UID:10002813-1701169200-1701172800@cmsa.fas.harvard.edu SUMMARY:Remarkable symmetries of rotating black holes DESCRIPTION:General Relativity Seminar \nSpeaker: David Kubiznak (Charles University) \nTitle: Remarkable symmetries of rotating black holes \nAbstract: It is well known that the Kerr geometry admits a non-trivial Killing tensor and its ‘square root’ known as the Killing-Yano tensor. These two objects stand behind Carter’s constant of geodesic motion as well as allow for separability of test field equations in this background. The situation is even more remarkable in higher dimensions\, where a single object — the principal Killing-Yano tensor — generates a tower of explicit and hidden symmetries responsible for integrability of geodesics and separability of test fields around higher-dimensional rotating black holes. Interestingly\, similar yet different structure is already present for the slowly rotating black holes described by the `magic square’ version of the Lense-Thirring solution\, giving rise to a geometrically preferred spacetime that can be cast in the Painleve-Gullstrand form and admits a tower of exact rank-2 and higher rank Killing tensors whose number rapidly grows with the number of spacetime dimensions. URL:https://cmsa.fas.harvard.edu/event/gr_112823/ CATEGORIES:General Relativity Seminar ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-GR-Seminar-11.28.23_Page_1.png END:VEVENT BEGIN:VEVENT DTSTART;TZID=America/New_York:20231128T120000 DTEND;TZID=America/New_York:20231128T130000 DTSTAMP:20260503T163824 CREATED:20240222T113148Z LAST-MODIFIED:20240222T113148Z UID:10002809-1701172800-1701176400@cmsa.fas.harvard.edu SUMMARY:A random matrix model towards the quantum chaos transition conjecture DESCRIPTION:Probability Seminar \nSpeaker: Jun Yin (UCLA) \nTitle: A random matrix model towards the quantum chaos transition conjecture \nAbstract: The Quantum Chaos Conjecture has long fascinated researchers\, postulating a critical spectrum phase transition that separates integrable systems from chaotic systems in quantum mechanics. In the realm of integrable systems\, eigenvectors remain localized\, and local eigenvalue statistics follow the Poisson distribution. Conversely\, chaotic systems exhibit delocalized eigenvectors\, with local eigenvalue statistics mirroring the Sine kernel distribution\, akin to the standard random matrix ensembles GOE/GUE. \nThis talk delves into the heart of the Quantum Chaos Conjecture\, presenting a novel approach through the lens of random matrix models. By utilizing these models\, we aim to provide a clear and intuitive demonstration of the same phenomenon\, shedding light on the intricacies of this long-standing conjecture. URL:https://cmsa.fas.harvard.edu/event/probability-112823/ CATEGORIES:Probability Seminar ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-Special-Seminar-11.28.23.png END:VEVENT BEGIN:VEVENT DTSTART;TZID=America/New_York:20231129T170000 DTEND;TZID=America/New_York:20231129T180000 DTSTAMP:20260503T163824 CREATED:20240221T100735Z LAST-MODIFIED:20240221T100813Z UID:10002773-1701277200-1701280800@cmsa.fas.harvard.edu SUMMARY:Anomalous Landau level analog in solids: search and implications for 2d heterostructures DESCRIPTION:Topological Quantum Matter Seminar \nSpeaker: Valentin Crepel\, Flatiron Institute \nTitle: Anomalous Landau level analog in solids: search and implications for 2d heterostructures \nAbstract: The recent experimental observation of fractional Chen insulators — the analog of fractional quantum Hall states realized in absence of any applied magnetic field — calls for more detailed theoretical investigations of the special conditions allowing their emergence. To gain some insight on this problem\, we can rely on (i) our extensive knowledge of the physical properties of Landau levels\, and (ii) the identification of their exact solid state analogs. \nIn this talk\, (i-ii) will be discussed in the case of ”anomalous Landau levels”\, which are protected by an index theorem\, and whose most famous representative are the zero-th Landau levels of graphene. In particular\, I will derive the generic form of Bloch wave functions realizing the analog of such anomalous Landau levels\, and argue that twisted transition metal dichalcogenides homobilayers (in which fractional Chern insulators were first discovered) almost realize such anomalous bands. URL:https://cmsa.fas.harvard.edu/event/tqms_112923/ LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States CATEGORIES:Topological Quantum Matter Seminar ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-Topological-Seminar-11.29.23.docx-1_Page_1.png END:VEVENT BEGIN:VEVENT DTSTART;TZID=America/New_York:20231130T160000 DTEND;TZID=America/New_York:20231130T170000 DTSTAMP:20260503T163824 CREATED:20240223T052452Z LAST-MODIFIED:20240223T052528Z UID:10002815-1701360000-1701363600@cmsa.fas.harvard.edu SUMMARY:A Gaussian convexity for logarithmic moment generating function DESCRIPTION:Probability Seminar \nSpeaker: Wei-Kuo Chen (University of Minnesota) \nTitle: A Gaussian convexity for logarithmic moment generating function \nAbstract: Convex functions of Gaussian vectors are prominent objectives in many fields of mathematical studies. In this talk\, I will establish a new convexity for the logarithmic moment generating function for this object and draw two consequences. The first leads to the Paouris-Valettas small deviation inequality that arises from the study of convex geometry. The second provides a quantitative bound for the Dotsenko-Franz-Mezard conjecture in the Sherrington-Kirkpatrick mean-field spin glass model\, which states that the logarithmic anneal partition function of negative replica is asymptotically equal to the free energy. \n  URL:https://cmsa.fas.harvard.edu/event/probability-113023/ LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States CATEGORIES:Probability Seminar ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-Probability-Seminar-11.30.23.png END:VEVENT BEGIN:VEVENT DTSTART;TZID=America/New_York:20231201T120000 DTEND;TZID=America/New_York:20231201T130000 DTSTAMP:20260503T163824 CREATED:20240227T112716Z LAST-MODIFIED:20240227T112731Z UID:10002878-1701432000-1701435600@cmsa.fas.harvard.edu SUMMARY:An introduction to mixture of experts in deep learning DESCRIPTION:Member Seminar \nSpeaker: Samy Jelassi \nTitle: An introduction to mixture of experts in deep learning \nAbstract: Scale has opened new frontiers in natural language processing – but at a high cost. Mixture-of-Experts (MoE) have been proposed as a path to even larger and more capable language models. They select different parameters for each incoming example. By doing so\, the parameter count is decoupled from the compute per example leading to very large\, but efficient models. In this talk\, I will review the concept of mixture of experts\, provide a basic description of the Switch Transformers model\, characterize some of their behaviors and conclude by highlighting some open problems in the field. This talk is mainly based on the following papers: https://arxiv.org/pdf/2101.03961.pdf\, https://arxiv.org/pdf/2209.01667.pdf . URL:https://cmsa.fas.harvard.edu/event/member-seminar-12123/ LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States CATEGORIES:Member Seminar END:VEVENT BEGIN:VEVENT DTSTART;TZID=America/New_York:20231201T163000 DTEND;TZID=America/New_York:20231201T173000 DTSTAMP:20260503T163824 CREATED:20230802T170029Z LAST-MODIFIED:20240813T162053Z UID:10001173-1701448200-1701451800@cmsa.fas.harvard.edu SUMMARY:A Plane Defect in the 3d O(N) Model DESCRIPTION:Quantum Matter Seminar \nSpeaker: Abijith Krishnan (MIT) \nTitle: A Plane Defect in the 3d O(N) Model \nAbstract: It was recently found that the classical 3d O(N) model in the semi-infinite geometry can exhibit an “extraordinary-log” boundary universality class\, where the spin-spin correlation function on the boundary falls off as (log x)^(-q). This universality class exists for a range 2≤N3. In this talk\, I’ll extend this result to the 3d O(N) model in an infinite geometry with a plane defect. I’ll explain using the renormalization group (RG) that the extraordinary-log universality class is present for any finite N≥2\, and that a line of defect fixed points is present at N=∞. This line of defect fixed points is lifted to the ordinary\, special (no defect) and extraordinary-log universality classes by 1/N corrections. I’ll show that the line of defect fixed points and the 1/N corrections agree with an a-theorem by Jensen and O’Bannon for 3d CFTs with a boundary. Finally\, I’ll conclude by noting some physical systems where the extraordinary-log universality class can be observed. \n  URL:https://cmsa.fas.harvard.edu/event/qm_33123/ LOCATION:Hybrid CATEGORIES:Quantum Matter ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-Topological-Seminar-12.01.23.png END:VEVENT BEGIN:VEVENT DTSTART;TZID=America/New_York:20231201T163000 DTEND;TZID=America/New_York:20231201T173000 DTSTAMP:20260503T163824 CREATED:20240222T101228Z LAST-MODIFIED:20240222T103010Z UID:10002799-1701448200-1701451800@cmsa.fas.harvard.edu SUMMARY:Quantum information: the interplay of mathematics and physics DESCRIPTION:Topological Quantum Matter Seminar \nSpeaker: Kaifeng Bu (Harvard University) \nTitle: Quantum information: the interplay of mathematics and physics \nAbstract: I will provide an introduction to quantum information\, which points to a new connection with experiment on the one hand\, and a potential new area of mathematical analysis on the other. I will introduce two recent results about the application of this new area in quantum information: (1) a novel Quantum Central Limit Theorem (QCLT)\, and (2) a physically realizable protocol for testing and measuring quantum advantage. This talk is based on a collaboration with Arthur Jaffe\, and Weichen Gu (PNAS120(25)2023\, arXiv: 2302.08423\, arXiv:2306.09292). \n  URL:https://cmsa.fas.harvard.edu/event/tqms_12123/ LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States CATEGORIES:Topological Quantum Matter Seminar ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-Topological-Seminar-12.01.23.png END:VEVENT BEGIN:VEVENT DTSTART;TZID=America/New_York:20231204T103000 DTEND;TZID=America/New_York:20231204T113000 DTSTAMP:20260503T163824 CREATED:20240222T065433Z LAST-MODIFIED:20240222T152910Z UID:10002786-1701685800-1701689400@cmsa.fas.harvard.edu SUMMARY:CM-minimizers and standard models of Fano fibrations over curves DESCRIPTION:Algebraic Geometry in String Theory Seminar \n\nSpeaker: Maksym Fedorchuk (Boston College) \nTitle: CM-minimizers and standard models of Fano fibrations over curves \nAbstract: A recent achievement in K-stability of Fano varieties is an algebro-geometric construction of a projective moduli space of K-polystable Fanos. The ample line bundle on this moduli space is the CM line bundle of Tian. One of the consequences of the general theory is that given a family of K-stable Fanos over a punctured curve\, the polystable filling is the one that minimizes the degree of the CM line bundle after every finite base change. A natural question is to ask what are the CM-minimizers without base change. In answering this question\, we arrive at a theory of Koll\’ar stability for fibrations over one-dimensional bases\, and standard models of Fano fibrations. I will explain the joint work with Hamid Abban and Igor Krylov in which we show that the CM-minimizers for del Pezzo fibrations are Corti’s standard models and related work in progress on quartic threefold hypersurfaces. \n\n  URL:https://cmsa.fas.harvard.edu/event/agst-12423/ LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States CATEGORIES:Algebraic Geometry in String Theory Seminar ATTACH;FMTTYPE=image/jpeg:https://cmsa.fas.harvard.edu/media/CMSA-AGIST-12.04.23-scaled.jpg END:VEVENT BEGIN:VEVENT DTSTART;TZID=America/New_York:20231204T140000 DTEND;TZID=America/New_York:20231204T150000 DTSTAMP:20260503T163824 CREATED:20240226T112024Z LAST-MODIFIED:20240226T112046Z UID:10002869-1701698400-1701702000@cmsa.fas.harvard.edu SUMMARY:The Fractional Quantum Hall Effect at ν=5/2: Past\, Recent\, and Future DESCRIPTION:Topological Quantum Matter Seminar \nSpeaker:  Ken K. W. Ma (Northeastern University) \nTitle: The Fractional Quantum Hall Effect at ν=5/2: Past\, Recent\, and Future \nAbstract: The discovery of fractional quantum Hall (FQH) states started a new chapter in modern physics. Nowadays\, more than 70 FQH states at different filling factors have been observed. Among them\, the FQH state at the filling factor ν=5/2 in GaAs (or the 5/2 state) remains one of the most special and attractive states. Since its discovery in 1987\, different possible topological orders have been proposed to describe the 5/2 state. Some of them can host an exotic type of particles\, known as non-Abelian anyons. Recent experiments have provided more insights into the understanding of the 5/2 state\, but its underlying nature is still under debate. \nIn this talk\, I will review the basics of the 5/2 state [1] and a more unified theoretical description of different possible topological orders of the 5/2 state that we have recently proposed [2]. I will also review the groundbreaking thermal Hall conductance experiment [3] and the follow-up quantum Hall interface experiments by the Weizmann Institute group [4\, 5]\, and discuss what possible lessons that we can learn from the experimental results. Lastly\, I will talk about some possible directions and related topics for future investigations. \nReferences: \n[1] K. K. W. Ma\, M. R. Peterson\, V. W. Scarola\, and K. Yang\, “Fractional quantum Hall effect at the filling factor ν = 5/2” in Encyclopedia of Condensed Matter Physics (Second Edition)\, edited by T. Chakraborty\, Academic Press (2024).\n[2] K. K. W. Ma and D. E. Feldman\, “The sixteenfold way and the quantum Hall effect at half-integer filling factors”\, Phys. Rev. B 100\, 035302 (2019).\n[3] M. Banerjee\, M. Heiblum\, V. Umansky\, D. E. Feldman\, Y. Oreg\, and A. Stern\, “Observation of half-integer thermal Hall conductance”\, Nature (London) 559\, 205 (2018).\n[4] B. Dutta\, W. Yang\, R. Melcer\, H. K. Kundu\, M. Heiblum\, V. Umansky\, Y. Oreg\, A. Stern\, D. Mross\, “Distinguishing between non-Abelian topological orders in a quantum Hall system”\, Science 375\, 193 (2021).\n[5] B. Dutta\, V. Umansky\, M. Banerjee\, and M. Heiblum\, “Isolated ballistic non-Abelian interface channel”\, Science 377\, 1198 (2022). \n  URL:https://cmsa.fas.harvard.edu/event/tqms_12423/ LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States CATEGORIES:Topological Quantum Matter Seminar ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-Topological-Seminar-12.04.23.png END:VEVENT BEGIN:VEVENT DTSTART;TZID=America/New_York:20231204T163000 DTEND;TZID=America/New_York:20231204T173000 DTSTAMP:20260503T163824 CREATED:20240223T075301Z LAST-MODIFIED:20240223T075301Z UID:10002830-1701707400-1701711000@cmsa.fas.harvard.edu SUMMARY:Analysis of ALH* gravitational instantons DESCRIPTION:Speaker: Xuwen Zhu (Northeastern) \nTitle: Analysis of ALH* gravitational instantons \nAbstract: Gravitational instantons are non-compact Calabi-Yau metrics with L^2 bounded curvature and are categorized into six types. We will discuss one such type called ALH* metrics which has a non-compact end modelled by the Calabi ansatz with inhomogeneous collapsing near infinity. Such metrics appeared recently in the works on SYZ conjecture\, as well as the scaling bubble limits for codimension-3 collapsing of K3 surfaces\, where the study of its Laplacian played a central role. In this talk I will talk about the Fredholm mapping property and L^2 cohomology of such metrics. This is ongoing work joint with Rafe Mazzeo. URL:https://cmsa.fas.harvard.edu/event/colloquium-12423/ LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States CATEGORIES:Colloquium ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-Colloquium-12.04.2023.docx-1.png END:VEVENT BEGIN:VEVENT DTSTART;TZID=America/New_York:20231205T110000 DTEND;TZID=America/New_York:20231205T120000 DTSTAMP:20260503T163824 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:20231205T123000 DTEND;TZID=America/New_York:20231205T133000 DTSTAMP:20260503T163824 CREATED:20240223T084615Z LAST-MODIFIED:20240223T084615Z UID:10002841-1701779400-1701783000@cmsa.fas.harvard.edu SUMMARY:CMSA Q and A Seminar 12/5/2023 DESCRIPTION:CMSA Q and A Seminar \nSpeakers: Mike Douglas (Harvard CMSA) and Anurag Anshu (Harvard Computer Science) \nTopics: \nMike Douglas: What are scaling laws in deep learning? \nAnurag Anshu: What’s the difference between classical information theory and quantum information theory (or classical computation vs quantum computation)? \n  URL:https://cmsa.fas.harvard.edu/event/cmsaqa_12523/ LOCATION:Common Room\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States CATEGORIES:CMSA Q&A Seminar END:VEVENT BEGIN:VEVENT DTSTART;TZID=America/New_York:20231207T130000 DTEND;TZID=America/New_York:20231207T140000 DTSTAMP:20260503T163824 CREATED:20240223T055715Z LAST-MODIFIED:20240223T055715Z UID:10002823-1701954000-1701957600@cmsa.fas.harvard.edu SUMMARY:Active structures and flows in living cells DESCRIPTION:Active Matter Seminar\n\n\nSpeaker: Michael Shelley (Flatiron) \nTitle: Active structures and flows in living cells \nAbstract: Flows in the fluidic interior of living cells can serve biological function or act as signatures of how intracellular forces are exerted. I’ll discuss examples of each. One is understanding the emergence of cell-spanning vortical flows in large developing egg cells\, while the other arises in studying the nature of force transduction in single cell embryos moving towards their first cell division. Both involve the cytoskeleton\, that set of polymers\, cross-linkers\, and molecular motors that underlie much of the active mechanics within cells\, and has led to the development of new coarse-grained active matter models and novel instabilities. URL:https://cmsa.fas.harvard.edu/event/am-12723/ LOCATION:CMSA Room G10\, CMSA\, 20 Garden Street\, Cambridge\, MA\, 02138\, United States CATEGORIES:Active Matter Seminar ATTACH;FMTTYPE=image/png:https://cmsa.fas.harvard.edu/media/CMSA-Active-Matter-Seminar-12.07.23.docx-1.png END:VEVENT END:VCALENDAR