• Neural Optimal Stopping Boundary

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

    Speaker: Max Reppen (Boston University) Title: Neural Optimal Stopping Boundary Abstract:  A method based on deep artificial neural networks and empirical risk minimization is developed to calculate the boundary separating the stopping and continuation regions in optimal stopping. The algorithm parameterizes the stopping boundary as the graph of a function and introduces relaxed stopping rules based on fuzzy […]

  • Interacting Active Matter

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

    Active Matter Seminar Speaker: Amin Doostmohammadi, Niels Bohr Institute, University of Copenhagen Title: Interacting Active Matter Abstract: I will focus on the interaction between different active matter systems. In particular, I will describe recent experimental and modeling results that reveal how interaction forces between adhesive cells generate activity in the cell layer and lead to a […]

  • Third Annual Yip Lecture

    Harvard Science Center 1 Oxford Street, Cambridge, MA

    Andrew Strominger will give the Third Annual Yip Lecture on February 2, 2023. Time: 7:00-8:00 pm ET Location: Harvard Science Center Hall A   Title: Black Holes: The Most Mysterious Objects in the Universe Abstract: In the last decade black holes have come to center stage in both theoretical and observational science. Theoretically, they were […]

  • Fracton orders in hyperbolic space and its excitations with fractal mobility

    Virtual

    Quantum Matter Seminar Speaker: Han Yan (Rice U) Title: Fracton orders in hyperbolic space and its excitations with fractal mobility Abstract: Unlike ordinary topological quantum phases, fracton orders are intimately dependent on the underlying lattice geometry. In this work, we study a generalization of the X-cube model, on lattices embedded in a stack of hyperbolic […]

  • Motivic Geometry of Two-Loop Feynman Integrals

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

    Member Seminar Speaker: Chuck Doran Title: Motivic Geometry of Two-Loop Feynman Integrals Abstract: We study the geometry and Hodge theory of the cubic hypersurfaces attached to two-loop Feynman integrals for generic physical parameters. We show that the Hodge structure attached to planar two-loop Feynman graphs decomposes into a mixed Tate piece and a variation of Hodge structure from […]

  • From spin glasses to Boolean circuits lower bounds – Algorithmic barriers from the overlap gap property

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

    Speaker: David Gamarnik (MIT) Title: From spin glasses to Boolean circuits lower bounds. Algorithmic barriers from the overlap gap property Abstract: Many decision and optimization problems over random structures exhibit an apparent gap between the existentially optimal values and algorithmically achievable values. Examples include the problem of finding a largest independent set in a random graph, the problem […]

  • Bakry-Emery theory and renormalisation

    Hybrid

    Probability Seminar Speaker: Roland Bauerschmidt (Cambridge) Title: Bakry-Emery theory and renormalisation Abstract: I will discuss an approach to log-Sobolev inequalities that combines the Bakry-Emery theory with renormalisation and present several applications. These include log-Sobolev inequalities with polynomial dependence for critical Ising models on Z^d when d>4 and singular SPDEs with uniform dependence of the log-Sobolev […]

  • Quasinormal modes and Ruelle resonances: mathematician’s perspective

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

    https://youtu.be/FyJ6TieNQBc General Relativity Seminar Speaker: Maciej Zworski, UC Berkeley Title: Quasinormal modes and Ruelle resonances: mathematician's perspective Abstract: Quasinormal modes of gravitational waves and Ruelle resonances in hyperbolic classical dynamics share many general properties and can be considered "scattering resonances": they appear in expansions of correlations, as poles of Green functions and are associated to […]

  • Special Lectures on Machine Learning and Protein Folding

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

    The CMSA hosted a series of three 90-minute lectures on the subject of machine learning for protein folding. Thursday Feb. 9, Thursday Feb. 16, & Thursday March 9, 2023, 3:30-5:00 pm ET Location: G10, CMSA, 20 Garden Street, Cambridge MA 02138 & via Zoom     Speaker: Nazim Bouatta, Harvard Medical School Abstract: AlphaFold2, a […]

  • Non-invertible Symmetry Enforced Gaplessness

    Virtual

    Quantum Matter Seminar Speaker: Ho Tat Lam (MIT) Title: Non-invertible Symmetry Enforced Gaplessness Abstract: Quantum systems in 3+1-dimensions that are invariant under gauging a one-form symmetry enjoy novel non-invertible duality symmetries encoded by topological defects. These symmetries are renormalization group invariants which constrain infrared dynamics. We show that such non-invertible symmetries often forbid a symmetry-preserving vacuum state […]

  • Parity and Cobordism

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

    Swampland Seminar Speaker: Jake McNamara (Caltech) Title: Parity and Cobordism Abstract: The swampland cobordism conjecture provides a convenient way to discuss conserved charges associated with the topology of spacetime. However, much of the power of the cobordism conjecture comes from a mathematical black box: the Adams spectral sequence. In this talk, I will give physical meaning to […]

  • Complete Calabi-Yau metrics: Recent progress and open problems

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

    Speaker: Tristan Collins, MIT Title: Complete Calabi-Yau metrics: Recent progress and open problems Abstract: Complete Calabi-Yau metrics are fundamental objects in Kahler geometry arising as singularity models or "bubbles" in degenerations of compact Calabi-Yau manifolds.  The existence of these metrics and their relationship with algebraic geometry are the subjects of several long standing conjectures due […]