• Mathematics around Twisted Holography

    CMSA Room G10 CMSA, 20 Garden Street, Cambridge, MA, United States

    Geometry and Quantum Theory Seminar Speaker: Keyou Zeng (CMSA) Title: Mathematics around Twisted Holography Abstract: The holography principle is an important idea in physics and has been widely studied since the 90s. Twisted holography offers a way to simplify physical holography models through the procedure called twisting. In the first part of the talk, I’ll […]

  • Symplectic duality in examples

    Science Center Hall E 1 Oxford Street, Cambridge, MA, United States

    Geometry and Quantum Theory Seminar Speaker: Vasily Krylov, Harvard CMSA & Math Title: Symplectic duality in examples Abstract: Over the past twenty years, mathematicians and physicists have shown increasing interest in studying certain Poisson varieties, known as “symplectic singularities.” Many of these objects naturally arise as Higgs or Coulomb branches of certain TQFTs and, therefore, […]

  • Topological Invariants of gapped states through cosheaves

    Science Center Hall E 1 Oxford Street, Cambridge, MA, United States

    Geometry and Quantum Theory Seminar Speaker: Bowen Yang, Harvard CMSA Title: Topological Invariants of gapped states through cosheaves Abstract: We provide a proper mathematical framework for the constructions of topological invariants of gapped quantum states and interpret topological invariants of gapped states as lattice analogs of ’t Hooft anomalies in Quantum Field Theory. Our secondary […]

  • Local complexity measures in modern parameterized function classes for supervised learning

    CMSA Room G10 CMSA, 20 Garden Street, Cambridge, MA, United States

    Colloquium Speaker: Elisenda Grigsby, Boston College Title: Local complexity measures in modern parameterized function classes for supervised learning Abstract: The parameter space for any fixed architecture of neural networks serves as a proxy during training for the associated class of functions - but how faithful is this representation? For any fixed feedforward ReLU network architecture, it […]

  • Skein traces and curve counting

    Science Center Hall E 1 Oxford Street, Cambridge, MA, United States

    Geometry and Quantum Theory Seminar Speaker: Sunghyuk Park, Harvard CMSA Title: Skein traces and curve counting Abstract: Skein modules are vector space-valued invariants of 3-manifolds describing the space of line defects modulo skein relations (determined by a choice of a ribbon category). When the 3-manifold is S x I for some surface S, the skein […]

  • Topological Modular Forms, its equivariant refinements and relation with supersymmetric quantum field theories

    Science Center Hall E 1 Oxford Street, Cambridge, MA, United States

    Geometry and Quantum Theory Seminar Speaker: Mayuko Yamashita, Kyoto University Title: Topological Modular Forms, its equivariant refinements and relation with supersymmetric quantum field theories Abstract: This talk is about the Segal-Stolz-Teichner program, which is one of the most deep and interesting topics relating homotopy theory and physics. Mathematically, they propose a geometric model of TMF, […]

  • Higher Vapnik–Chervonenkis theory

    CMSA Room G10 CMSA, 20 Garden Street, Cambridge, MA, United States

    Colloquium Speaker: Artem Chernikov, University of Maryland Title: Higher Vapnik–Chervonenkis theory Abstract: Finite VC-dimension, a combinatorial property of families of sets, was discovered simultaneously by Vapnik and Chervonenkis in probabilistic learning theory, and by Shelah in model theory (where it is called NIP). It plays an important role in several areas including machine learning, combinatorics, mathematical […]

  • Fusion 2-Categories and their Classification

    Science Center Hall E 1 Oxford Street, Cambridge, MA, United States

    Geometry and Quantum Theory Seminar Speaker: Thibault Décoppet, Harvard University Title: Fusion 2-Categories and their Classification Abstract: Categorifying the classical notion of fusion (1-)category, fusion 2-categories were recently introduced. These objects have found many applications in Physics, most notably to the classification of topological orders, but also to the description of non-invertible symmetries in 2+1 dimensions. […]

  • Boundaries and duality for 3d gauge theories

    Science Center Hall E 1 Oxford Street, Cambridge, MA, United States

    Geometry and Quantum Theory Seminar Speaker: Ben Gammage, Harvard University Title: Boundaries and duality for 3d gauge theories Abstract: 3d N=4 supersymmetric gauge theory has a pair of topological twists, the A-model and B-model, the latter of which is also known as Rozansky-Witten theory. Conjecturally, boundary conditions for these TFTs ought to admit descriptions in […]

  • The mathematics of evolution

    CMSA Room G10 CMSA, 20 Garden Street, Cambridge, MA, United States

    Colloquium Speaker: Martin Nowak (Harvard) Title: The mathematics of evolution Abstract: All living systems are guided by evolutionary dynamics. Evolution is a search process which occurs in populations of reproducing individuals. The three fundamental forces of evolution are mutation, selection and cooperation. I will present basic ideas in the mathematical description of evolutionary dynamics, including quasi-species theory, evolutionary […]

  • Introduction to Factorization algebras

    Science Center Hall E 1 Oxford Street, Cambridge, MA, United States

    Geometry and Quantum Theory Seminar Speaker: Dan Freed, Harvard University Title: Introduction to Factorization algebras