• A new proof for the nonlinear stability of slowly-rotating Kerr-de Sitter

    Virtual

    https://youtu.be/jwvkS2A2dL8 General Relativity Seminar Speaker: Allen Fang (Princeton) Title: A new proof for the nonlinear stability of slowly-rotating Kerr-de Sitter Abstract: The nonlinear stability of the slowly-rotating Kerr-de Sitter family was first proven by Hintz and Vasy in 2016 using microlocal techniques. In my talk, I will present a novel proof of the nonlinear stability […]

  • Neutrino Masses from Generalized Symmetry Breaking

    Virtual

    Quantum Matter Seminar Speaker: Sungwoo Hong (U Chicago & KAIST) Title: Neutrino Masses from Generalized Symmetry Breaking Abstract: We explore generalized global symmetries in theories of physics beyond the Standard Model. Theories of Z′ bosons generically contain 'non-invertible' chiral symmetries, whose presence indicates a natural paradigm to break this symmetry by an exponentially small amount […]

  • Exact Many-Body Ground States from Decomposition of Ideal Higher Chern Bands: Applications to Chirally Twisted Graphene Multilayers

    Virtual

    Quantum Matter Seminar Speaker: Junkai Dong (Harvard University) Title: Exact Many-Body Ground States from Decomposition of Ideal Higher Chern Bands: Applications to Chirally Twisted Graphene Multilayers Abstract: Motivated by the higher Chern bands of twisted graphene multilayers, we consider flat bands with arbitrary Chern number C with ideal quantum geometry. While C>1 bands differ from […]

  • 3D gravity and gravitational entanglement entropy

    Virtual

    Quantum Matter Seminar Speaker: Gabriel Wong (Harvard CMSA) Title: 3D gravity and gravitational entanglement entropy Abstract: Recent progress in AdS/CFT has provided a good understanding of how the bulk spacetime is encoded in the entanglement structure of the boundary CFT. However, little is known about how spacetime emerges directly from the bulk quantum theory. We […]

  • Schwarzschild-like Topological Solitons in Gravity

    Virtual

    https://youtu.be/hhjIPdyIM3U General Relativity Seminar Speaker: Pierre Heidmann (Johns Hopkins) Title: Schwarzschild-like Topological Solitons in Gravity Abstract: We present large classes of non-extremal solitons in gravity that are asymptotic to four-dimensional Minkowski spacetime plus extra compact dimensions. They correspond to smooth horizonless geometries induced by topology in spacetime and supported by electromagnetic flux, which characterize coherent states of quantum gravity. We discuss […]

  • Topological symmetry in field theory

    Virtual

    Quantum Matter Seminar Speaker: Daniel S. Freed (U Texas) Title: Topological symmetry in field theory Abstract: Recently there has been lots of activity surrounding generalized notions of symmetry in quantum field theory, including “categorical symmetries,” “higher symmetries,” “noninvertible symmetries,” etc. Inspired by definitions of abstract (finite) groups and algebras and their linear actions, we introduce […]

  • Kardar-Parisi-Zhang dynamics in integrable quantum magnets

    Virtual

    Quantum Matter Seminar Speaker: Francisco Machado  (Berkeley/Harvard) Title: Kardar-Parisi-Zhang dynamics in integrable quantum magnets Abstract: Although the equations of motion that govern quantum mechanics are well-known, understanding the emergent macroscopic behavior that arises from a particular set of microscopic interactions remains remarkably challenging. One particularly important behavior is that of hydrodynamical transport; when a quantum system has a […]

  • Gravitational Wave, Angular Momentum, and Supertranslation Ambiguity

    Virtual

    General Relativity Seminar Speaker: Naqing Xie (Fudan University) Title: Gravitational Wave, Angular Momentum, and Supertranslation Ambiguity Abstract: The supertranslation ambiguity of angular momentum is a long-standing and conceptually important issue in general relativity. Recently, there appeared the first definition of angular momentum at null infinity that is supertranslation invariant. However, in the compact binary coalescence community, supertranslation […]

  • Unorientable Quantum Field Theories: From crosscaps to holography

    Virtual

    https://www.youtube.com/watch?v=0y2colQwY34 Quantum Matter Seminar Speaker: João Caetano (CERN) Title: Unorientable Quantum Field Theories: From crosscaps to holography Abstract: In two dimensions, one can study quantum field theories on unorientable manifolds by introducing crosscaps. This defines a class of states called crosscap states which share a few similarities with the notion of boundary states. In this talk, I […]

  • Insulating BECs and other surprises in dipole-conserving systems

    Virtual

    Quantum Matter Seminar Speaker: Ethan Lake (MIT) Title: Insulating BECs and other surprises in dipole-conserving systems Abstract: I will discuss recent work on bosonic models whose dynamics conserves both total charge and total dipole moment, a situation which can be engineered in strongly tilted optical lattices. Related models have received significant attention recently for their interesting out-of-equilibrium dynamics, […]

  • On the six-dimensional origin of non-invertible symmetries

    Virtual

    Quantum Matter Seminar Speaker: Michele Del Zotto (Uppsala University) Title: On the six-dimensional origin of non-invertible symmetries Abstract: I will present a review about recent progress in charting non-invertible symmetries for four-dimensional quantum field theories that have a six-dimensional origin. These include in particular N=4 supersymmetric Yang-Mills theories, and also a large class of N=2 […]

  • Topological Wick Rotation and Holographic duality

    Virtual

    Quantum Matter Seminar Speaker: Liang Kong (Sustech) Title: Topological Wick Rotation and Holographic duality Abstract: I will explain a new type of holographic dualities between n+1D topological orders with a chosen boundary condition and nD (potentially gapless) quantum liquids. It is based on the idea of topological Wick rotation, a notion which was first used […]