Today

  • 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, […]

  • 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 […]

  • 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 […]

  • 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 […]

  • Topology of the Fermi sea: Ordinary metals as topological materials

    Quantum Matter Seminar Speaker: Pok Man Tam (University of Pennsylvania) Title: Topology of the Fermi sea: Ordinary metals as topological materials Abstract: It has long been known that the quantum ground state of a metal is characterized by an abstract manifold in momentum space called the Fermi sea. Fermi sea can be distinguished topologically in […]

  • 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 […]

  • 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 […]

  • 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 […]

  • Non-Invertible Symmetries from Holography and Branes

    Virtual

    Quantum Matter Seminar Speaker: Federico Bonetti (Oxford) Title: Non-Invertible Symmetries from Holography and Branes Abstract:  The notion of global symmetry in quantum field theory (QFT) has witnessed dramatic generalizations in the past few years. One of the most exciting developments has been the identification of 4d QFTs possessing non-invertible symmetries, i.e. global symmetries whose generators […]

  • Phase Fluctuations in Two-Dimensional Superconductors and Pseudogap Phenomenon

    Virtual

    Quantum Matter Seminar Speaker: Yang Qi (Fudan) Title: Phase Fluctuations in Two-Dimensional Superconductors and Pseudogap Phenomenon Abstract: We study the phase fluctuations in the normal state of a general two-dimensional (2d) superconducting system with s-wave pairing. The effect of phase fluctuations of the pairing fields can be dealt with perturbatively using disorder averaging, after we […]

  • CMSA QMMP 1.24.23

    Reflections on Parity Breaking

    Virtual

    Quantum Matter Seminar Speakers: Jacob McNamara (Caltech) and Matthew Reece (Harvard) Title: Reflections on Parity Breaking Abstract: One approach to the Strong CP Problem (known as Nelson-Barr models) is to assume that parity is a gauge symmetry, which is spontaneously broken in the world around us. In this talk, we will describe the formal meaning […]

  • CMSA QMMP 1.30.23

    Group Invariant States as Many-Body Scars

    Virtual

    Quantum Matter Seminar Title: Group Invariant States as Many-Body Scars Speaker: Igor R. Klebanov (Princeton University) Abstract: Quantum many-body scars have been an active area of research in Condensed Matter Physics for several years. In some many-body systems, the Hilbert space breaks up into a large ergodic sector and a much smaller scar subspace. It […]