Quantum Matter Seminar Speaker: Rahul Sahay (Harvard) Title: Quantum Spin Lakes: NISQ-Era Spin Liquids from Non-Equilibrium Dynamics Abstract: While many-body quantum systems can in principle host exotic quantum spin liquid (QSL) states, realizing them as ground states in experiments can be prohibitively difficult. In this talk, we show how non-equilibrium dynamics can provide a streamlined […]
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 […]
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 […]
https://youtu.be/0gWCm0wmgOY General Relativity Seminar Speaker: Chiara Toldo (Harvard) Title: Near extremal de Sitter black holes and JT gravity Abstract: In this talk I will explore the thermodynamic response near extremality of charged black holes in four-dimensional Einstein-Maxwell theory with a positive cosmological constant. The latter exhibit three different extremal limits, dubbed cold, Nariai and ultracold configurations, with […]
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 […]
https://youtu.be/ParxdL5gREI General Relativity Seminar Speaker: Prashant Kocherlakota (BHI) Title: Testing spacetime geometry with images of supermassive compact objects: Current status and the future Abstract: Astrophysical black holes (BHs) are expected to be described by the Kerr solution of the Einstein equations. Several frameworks have recently been developed to parametrically deform the Kerr metric in significantly […]
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 […]
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 […]
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 […]
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 […]
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 […]
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 […]