• Exotic quantum matter: From lattice gauge theory to hyperbolic lattices

    Virtual

    Title: Exotic quantum matter: From lattice gauge theory to hyperbolic lattices Abstract: This talk, in two parts, will discuss two (unrelated) instances of exotic quantum matter. In the first part, I will discuss quantum critical points describing possible transitions out of the Dirac spin liquid, towards either symmetry-breaking phases or topologically ordered spin liquids. I […]

  • Swampland Seminar Series

    During the 2021-22 academic year, the CMSA will be co-hosting a seminar on Swampland, with the Harvard Physics Department, organized by Miguel Montero, Cumrun Vafa, Irene Valenzuela. This seminar is a part of the Swampland Program. This seminar will take place on Mondays at 10:00 am – 11:30 am (Boston time). To learn how to attend, please subscribe here. Talks will […]

  • Derived categories of nodal quintic del Pezzo threefolds

    Abstract: Conifold transitions are important algebraic geometric constructions that have been of special interests in mirror symmetry, transforming Calabi-Yau 3-folds between A- and B-models. In this talk, I will discuss the change of the quintic del Pezzo 3-fold (Fano 3-fold of index 2 and degree 5) under the conifold transition at the level of the […]

  • Cornering the universal shape of fluctuations and entanglement

    Virtual

    Title: Cornering the universal shape of fluctuations and entanglement Abstract: Understanding the fluctuations of observables is one of the main goals in physics. We investigate such fluctuations when a subregion of the full system can be observed, focusing on geometries with corners. We report that the dependence on the opening angle is super-universal: up to […]

  • The complexity of matrix multiplication approached via algebraic geometry and representation theory

    https://youtu.be/leONsS4LiV4 Speaker: JM Landsberg, Texas A&M Title: The complexity of matrix multiplication approached via algebraic geometry and representation theory Abstract: In 1968 V. Strassen discovered the way we usually multiply matrices is not the most efficient possible, and after considerable work by many authors, it is generally conjectured by computer scientists that as the size […]

  • Quantum gravity from quantum matter

    Virtual

    Title: Quantum gravity from quantum matter Abstract: We present a model of quantum gravity in which dimension, topology and geometry of spacetime are collective dynamical variables that describe the pattern of entanglement of underlying quantum matter. As spacetimes with arbitrary dimensions can emerge, the gauge symmetry is generalized to a group that includes diffeomorphisms in […]

  • 9/10/2021 General Relativity Seminar

    Title: Asymptotic localization, massive fields, and gravitational singularities Abstract: I will review three recent developments on Einstein’s field equations under low decay or low regularity conditions. First, the Seed-to-Solution Method for Einstein’s constraint equations, introduced in collaboration with T.-C. Nguyen generates asymptotically Euclidean manifolds with the weakest or strongest possible decay (infinite ADM mass, Schwarzschild […]

  • Threshold phenomena in random graphs and hypergraphs

    Member Seminar Speaker: Michael Simkin Title: Threshold phenomena in random graphs and hypergraphs Abstract: In 1959 Paul Erdos and Alfred Renyi introduced a model of random graphs that is the cornerstone of modern probabilistic combinatorics. Now known as the “Erdos-Renyi” model of random graphs it has far-reaching applications in combinatorics, computer science, and other fields. The […]

  • More Exact Results in Gauge Theories: Confinement and Chiral Symmetry Breaking

    Virtual

    Title: More Exact Results in Gauge Theories: Confinement and Chiral Symmetry Breaking Abstract: In this follow-up to Hitoshi Murayama’s talk “Some Exact Results in QCD-like and Chiral Gauge Theories”, I present a detailed analysis of the phases of $SO(N_c)$ gauge theory. Starting with supersymmetric $SO(N_c)$ with $N_F$ flavors, we extrapolate to the non-supersymmetric limit using […]

  • Gradient flows on totally nonnegative flag varieties

    Abstract: One can view a partial flag variety in C^n as an adjoint orbit inside the Lie algebra of n x n skew-Hermitian matrices. We use the orbit context to study the totally nonnegative part of a partial flag variety from an algebraic, geometric, and dynamical perspective. We classify gradient flows on adjoint orbits in […]

  • Decoding Divergent Distances

    Speaker: John Stout, Harvard University Title: Decoding Divergent Distances Abstract: Motivated by a relationship between the Zamolodchikov and NLSM metrics to the so-called quantum information metric, I will discuss recent work (2106.11313) on understanding infinite distance limits within the context of information theory. I will describe how infinite distance points represent theories that are hyper-distinguishable, in […]

  • Simplices in the Calabi–Yau web

    Abstract: Calabi–Yau manifolds of a given dimension are connected by an intricate web of birational maps. This web has deep consequences for the derived categories of coherent sheaves on such manifolds, and for the associated string theories. In particular, for 4-folds and beyond, I will highlight certain simplices appearing in the web, and identify corresponding derived […]