Today

  • Quantum Field Theory and Physical Mathematics

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

    Quantum Field Theory and Physical Mathematics Seminar Speaker: Kai Xu, Harvard Title: Finite Landscape of 6d N=(1,0) Supergravity Abstract: We present a bottom-up argument showing that the number of massless fields in six-dimensional quantum gravitational theories with eight supercharges is uniformly bounded. Specifically, we show that the number of tensor multiplets is bounded by T≤193, and the […]

  • The Combinatorics of the Amplituhedron – Tiles, Tilings, and Cluster Algebras

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

    Member Seminar Speaker: Matteo Parisi Title: The Combinatorics of the Amplituhedron – Tiles, Tilings, and Cluster Algebras Abstract: The amplituhedron is the image of the positive Grassmannian—the region of the Grassmannian where all Plücker coordinates are nonnegative—under a totally positive linear map. It is a far-reaching generalization of cyclic polytopes and hyperplane arrangements, and the positive […]

  • Mathematical Physics and Algebraic Geometry Seminar

    2d chiral Lagrangian for asymptotic dynamics for 4d (self-dual) Einstein gravity

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

    Mathematical Physics and Algebraic Geometry Seminar Speaker: Wei Bu (Harvard University) Title: 2d chiral Lagrangian for asymptotic dynamics for 4d (self-dual) Einstein gravity Abstract: In this talk, I will present a simple chiral 2d Lagrangian living on a 2d celestial sphere on the null boundary of 4d Minkowski space and briefly mention its first principal […]

  • BKL bounces outside homogeneity

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

    https://youtu.be/g8V7VeQwDtk General Relativity Seminar Speaker: Warren Li ( Princeton University) Title: BKL bounces outside homogeneity Abstract: In work spanning the late 20th century, physicists Belinski, Khalatnikov and Lifshitz (BKL) proposed a general ansatz for solutions to the Einstein (vacuum) equations near singularities. They suggest that the spacetime dynamics at different spatial points on the singularity decouple […]

  • Toward constructing a large-scale quantum computer based on TQFT

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

    Quantum Field Theory and Physical Mathematics Seminar Speaker: Liyuan Chen ( Harvard) Title: Toward constructing a large-scale quantum computer based on TQFT Abstract: Topological quantum computation, motivated by topological quantum field theory (TQFT), offers a promising path toward fault-tolerant universal quantum computation. However, the practical realization of such a system remains challenging due to the […]

  • Jack polynomials and enumeration of non-orientable maps

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

    Member Seminar Speaker: Houcine Ben Dali, Harvard CMSA Title: Jack polynomials and enumeration of non-orientable maps Abstract: A map is a graph embedded on a surface, which may be orientable or not. The representation theory of the symmetric group can be used to write the generating series of maps on orientable surfaces using Schur symmetric functions. Several […]

  • Mathematical Physics and Algebraic Geometry Seminar

    The Structure of the Flux Landscape

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

    Mathematical Physics and Algebraic Geometry Seminar Speaker: Damian Van de Heisteeg, Harvard CMSA Title: The Structure of the Flux Landscape Abstract: Identifying flux vacua in string theory with stabilized complex structure moduli presents a significant challenge, necessitating the minimization of a scalar potential complicated by infinitely many exponential corrections. In order to obtain exact results we […]

  • On the past maximal development of near-FLRW data for the Einstein scalar-field Vlasov system

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

    General Relativity Seminar Speaker: Liam Urban (University of Vienna) Title: On the past maximal development of near-FLRW data for the Einstein scalar-field Vlasov system Abstract: In recent years, the formation of Big Bang singularities has been increasingly well understood in presence of scalar-field matter, which suppresses the geometric oscillations that one generically expects otherwise. From a cosmological perspective, […]

  • Featured

    AI in math and theoretical physics: Status and prospects

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

    Colloquium Speaker: Michael Douglas, Harvard CMSA Title: AI in math and theoretical physics: status and prospects Abstract: AI is making great progress and has the potential to change how we work in unprecedented ways. In this talk I will survey a few recent works which illustrate the state of the art, some from my own research, […]

  • Featured

    Rational approximation and the AAA algorithm

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

    Colloquium Speaker: Nick Trefethen, Harvard University Title: Rational approximation and the AAA algorithm Approximation by rational functions used to be mainly a theoretical subject, but with the introduction of the AAA algorithm in 2018, it became computationally practical and indeed easy. The implications for what we can do numerically are enormous. This talk will outline […]

  • Topological to Gravitational Leptogenesis, via Ultra Unification 

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

    Quantum Field Theory and Physical Mathematics Seminar Speaker: Juven Wang (LIMS, Royal Institution) Title: Topological to Gravitational Leptogenesis, via Ultra Unification Abstract: We propose a new mechanism for leptogenesis, named Topological Leptogenesis, in which dark matter consists of topological order, so gapped anyon excitations decay to generate the Standard Model lepton asymmetry. Topological Leptogenesis is in […]

  • Smooth projective fibrations over the projective line and their sections

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

    Member Seminar Speaker: Iacopo Brivio Title: Smooth projective fibrations over the projective line and their sections Abstract: Suppose $f\colon X\to \mathbf{CP}^1$ is a smooth projective fibration, is it then true that $f$ has a section? This deceptively simple result was established by Seidel and McDuff using deep methods of symplectic geometry. Alex Pieloch recently generalized this to morphisms […]