Vasily Krylov

Geometry and Quantum Theory Seminar Speaker: Saman Habibi Esfahani (CMSA) Title: Geometric structures on gauge theoretic moduli spaces Abstract: Motivated by Witten’s study of instantons on S3 x S1, we survey some classical and recent results, programs, and conjectures on geometric structures, such as symplectic and hyperkahler, on moduli spaces of instantons and monopoles on various […]

Geometry and Quantum Theory Seminar Speaker: William Stewart Title: Constructing oriented TQFTs from twisted pivotal tensor categories Abstract: The cobordism hypothesis classifies n-dimensional oriented TQFTs in terms of SO(n) homotopy fixed point data. An SO(2) homotopy fixed point structure on a finite tensor category gives rise to a twisted pivotal structure (a more general notion […]

Geometry and Quantum Theory Seminar Speakers: Max Hübner, CMSA Title: Bi-HKT Manifolds, Sigma Models, Large N=4 and their String Constructions Abstract: We continue our review of Witten's paper "Instantons and the Large N=4 Algebra". We discuss the realization of large N=4 supersymmetry in the context of supersymmetric sigma-models, and discuss and motivate string theoretic duals […]

Geometry and Quantum Theory Seminar Speaker: Sanjay Raman, Harvard Title: Solitonic Symmetry: Cohomology with TFT Coefficients Abstract: We review the formalism of https://arxiv.org/pdf/2307.00939, which develops the theory of solitonic symmetry in quantum field theory. The algebraic structure of solitonic symmetry is determined by the fusion of topological functionals in a given path-integral formulation of topological field theory, and […]

Joint Math/CMSA Geometry and Quantum Theory Seminar Speaker: Lorenzo Riva, Harvard CMSA Title: TQFTs do not detect the Milnor sphere Abstract: I will talk about the recent paper of Gripaios and Randall-Williams with that title, where they prove that a functorial TQFT (i.e. a symmetric monoidal functor from the n-dimensional bordism category into a suitably […]

Joint Math/CMSA Geometry and Quantum Theory Seminar Speaker: Keyou Zeng (CMSA) Title: Line operators in holomorphic QFT Abstract: We will discuss the recent work (arxiv:2508.11749), which defines the so called dg shifted Yangian. I will discuss their origin from the study of 3d holomorphic topological field theories, a variant of 3d TQFT. A dg shifted Yangian […]

Joint Math/CMSA Geometry and Quantum Theory Seminar Speaker: Vasily Krylov, Harvard Title: 1-shifted Yangians from 1-shifted Lie bialgebras Abstract: In the previous talk, Keyou explained that the fusion of line defects in 3d holomorphic–topological field theories is expected to be governed by so-called DG-shifted Yangians. Following arXiv:2503.08770, I will present examples of such DG-shifted Yangians arising from […]

Joint Math/CMSA Geometry and Quantum Theory Seminar Speaker: Oswaldo Vázquez (Harvard) Title: A Mumford form on infinite Grassmannians Abstract: The Polyakov measure in bosonic string theory can be expressed in terms of the Mumford form, which is a trivializing section of a product of determinant line bundles over the moduli space of genus g curves. We […]

Joint Math/CMSA Geometry and Quantum Theory Seminar Speaker: Dan Freed, Harvard Math & CMSA Title: Abelian gauge fields and duality Abstract: Motivated by the new paper arXiv:2603.19161, I will give a general talk about abelian gauge fields, including duality. I will start with classical Maxwell theory, then discuss various “finite” examples, the typical p-form abelian […]

Joint Math/CMSA Geometry and Quantum Theory Seminar Speaker: Ahsan Khan, Harvard CMSA Title: Introduction to A-infty categories Abstract: I will give a pedagogical account of A-infty categories and the various places they show up in mathematical physics.  

Joint Math/CMSA Geometry and Quantum Theory Seminar Speaker: Lorenzo Riva, Harvard CMSA Title: The classifying space of a Morse flow category Abstract: Following a paper of Calle and Liu we show that, under suitable tameness assumptions, the classifying space of the Morse category associated to a manifold M with a Morse function recovers the homotopy […]