• Bass-Note Spectra of locally uniform geometries

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

    Colloquium Speaker: Peter Sarnak, IAS & Princeton University Title: Bass-Note Spectra of locally uniform geometries Abstract: We formulate and report on the problem of the Bass-Note Spectrum of an invariant operator as one varies over locally uniform geometries. In the Euclidean setting this recasts classical problems of Mahler from the geometry of numbers in a new […]

  • Algebraic approach to the bow construction

    Science Center 507 1 Oxford Street, Cambridge

    Geometry and Quantum Theory Seminar Speakers: Anadil Saeed Rao (Northeastern) and Vasily Krylov (CMSA/Harvard) Title: Algebraic approach to the bow construction Abstract: Anadil will finish his part of the talk. Vasily will then explain how to understand moduli spaces of instantons on R^4, monopoles on R^3, and instantons on Taub-NUT spaces algebraically as so-called bow varieties. We […]

  • Thinking Outside the Ballot Box

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

    Colloquium Speaker: Ariel Procaccia, Harvard University Title: Thinking Outside the Ballot Box Abstract: How should one design unprecedented democratic processes capable of handling enormous sets of alternatives like all possible policies, bills, or statements? I argue that this challenge can be addressed through a framework called generative social choice, which fuses the rigor of social choice theory […]

  • Factorizations for data analysis

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

    Colloquium Speaker: Anna Seigal, Harvard University Title: Factorizations for data analysis Abstract: We can find structure in data by factoring it into building blocks, which should be interpretable for the context at hand. A classical example is principal component analysis (PCA), which uses the eigendecomposition of the covariance matrix to find axes of variation in a dataset. Starting from […]

  • Fukaya category and gauge theory

    Science Center 507 1 Oxford Street, Cambridge

    Geometry and Quantum Theory Seminar Speaker: Saman Habibi Esfahani, Harvard CMSA Title: Fukaya category and gauge theory Abstract: After setting up some background, I will discuss the Fukaya $A_\ infty$-category and several instances where it appears in gauge theory, such as in the study of flat connections on Riemann surfaces, holomorphic sections of some hyperkähler […]

  • Higher categories of cobordisms

    Science Center 507 1 Oxford Street, Cambridge

    Geometry and Quantum Theory Seminar Speaker: Lorenzo Riva Title: Higher categories of cobordisms Abstract: I will give a brief introduction to topological field theories from a higher categorical perspective. After saying a few things about higher categories, I will define a family of n-categories of bordisms and talk about their universal properties. I will try […]

  • Geometry and Quantum Theory Seminar

    Science Center 507 1 Oxford Street, Cambridge

    Geometry and Quantum Theory Seminar Speaker 1: Max Hubner, CMSA Title: On Topological Structures in String Theory Abstract: Geometric engineering constructions in string theory often realize QFTs relative to an extra-dimensional geometry. This perspective parallels the symmetry TFT construction where a QFT is presented relative to its extra-dimensional symmetry quiche. Unsurprisingly, as we will discuss, […]

  • A Classifying Space for Phases of Matrix Product States

    Science Center 507 1 Oxford Street, Cambridge

    Geometry and Quantum Theory Seminar Speakers: Daniel Spiegel, Harvard Math Title: A Classifying Space for Phases of Matrix Product States Abstract: Alexei Kitaev has conjectured that there should be a loop spectrum consisting of spaces of gapped invertible quantum spin systems, indexed by spatial dimension d of the lattice. Motivated by Kitaev’s conjecture, I will […]

  • Geometry and Quantum Theory Seminar

    Science Center 507 1 Oxford Street, Cambridge

    Geometry and Quantum Theory Seminar Speaker: Dylan Galt, Harvard (60 minute talk) Title: What is a "nonlinear" near-symplectic form? Abstract: In this talk, I will explain how one might understand this question and why a possible answer can be found in the geometry of coassociative 4-folds, a special class of minimal submanifolds discovered by Harvey and Lawson.   […]

  • Geometry and Quantum Theory Seminar

    Science Center 507 1 Oxford Street, Cambridge

    Geometry and Quantum Theory Seminar Speakers: (1) Elliott Gesteau, CMSA (60 min) and  (2) Sanjay Raman, Harvard (30 min) (1) Title: Holography for closed universes Abstract: Recent advances in holography and black hole physics have prompted a number of new puzzles related to the physics of closed universes, which can be argued to have a one-dimensional […]

  • A fully local extension of Chern-Simons theory

    Science Center 507 1 Oxford Street, Cambridge

    Geometry and Quantum Theory Seminar Speaker: Dan Freed Title: A fully local extension of Chern-Simons theory Abstract: The Reshetikhin-Turaev-Witten invariants of 3-manifolds fit into a 3-dimensional topological field theory that also attaches invariants to 2-manifolds and 1-manifolds. It has long been asked to extend to invariants of 0-manifolds as well, a question that often takes […]