• Correlation decay for finite lattice gauge theories

    Science Center 232 Harvard Science Center, 1 Oxford Street, Cambridge MA 02138

    Probability Seminar Speaker: Arka Adhikari (Stanford) Title: Correlation decay for finite lattice gauge theories Abstract: In the setting of lattice gauge theories with finite (possibly non-Abelian) gauge groups at weak coupling, we prove exponential decay of correlations for a wide class of gauge invariant functions, which in particular includes arbitrary functions of Wilson loop observables. […]

  • A 6-year journey: from gravitational anomaly to a unified theory of generalized symmetry

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

    Quantum Matter Seminar Speaker: Xiao-Gang Wen (MIT) Title: A 6-year journey: from gravitational anomaly to a unified theory of generalized symmetry Abstract: Emergent symmetry can be generalized symmetry beyond (higher) group description and/or can be anomalous. I will describe a unified theory for generalized symmetry based on symmetry/topological-order correspondence. I will also discuss some applications […]

  • Pole skipping, quasinormal modes, shockwaves and their connection to chaos

    https://youtu.be/cxdPO4L4GDk General Relativity Seminar Speaker: Diandian Wang(Harvard University) Title: Pole skipping, quasinormal modes, shockwaves and their connection to chaos Abstract: A chaotic quantum system can be studied using the out-of-time-order correlator (OTOC). I will tell you about pole skipping — a recently discovered feature of the retarded Green’s function — that seems to also know things: things like the Lyapunov […]

  • Homotopy classes of loops of Clifford unitaries

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

    https://youtu.be/vYXTKTmNFHg Topological Quantum Matter Seminar Speaker: Roman Geiko, UCLA Title: Homotopy classes of loops of Clifford unitaries Abstract: We study Clifford locality-preserving unitaries and stabilizer Hamiltonians by means of Hermitian K-theory. We demonstrate how the notion of algebraic homotopy of modules over Laurent polynomial rings translates into the connectedness of two short-range entangled stabilizer Hamiltonians […]

  • Phase transitions out of quantum Hall states in moire TMD bilayers

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

    Topological Quantum Matter Seminar Speaker: Xueyang Song (MIT) Title: Phase transitions out of quantum Hall states in moire TMD bilayers Abstract: Motivated by the recent experimental breakthroughs in observing Fractional Quantum Anomalous Hall (FQAH) states in moir\'e Transition Metal Dichalcogenide (TMD) bilayers, we propose and study various unconventional phase transitions between quantum Hall phases and Fermi […]

  • Anomalies of Non-Invertible Symmetries

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

    Quantum Matter Seminar Speaker: Clay Córdova (U Chicago) Title: Anomalies of Non-Invertible Symmetries

  • Frustration-free states of cell fate networks: the case of the epithelial-mesenchymal transition

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

    Active Matter Seminar Speaker: Herbert Levine (Northeastern) Title: Frustration-free states of cell fate networks: the case of the epithelial-mesenchymal transition Abstract: Cell fate decisions are made by allowing external signals to govern the steady-state pattern adopted by networks of interacting regulatory factors governing transcription and translation. One of these decisions, of importance for both developmental processes […]

  • Quantum UV-IR map and curve counts in skeins

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

    Member Seminar Speaker: Sunghyuk Park Title: Quantum UV-IR map and curve counts in skeins Abstract: Quantum UV-IR map (a.k.a. q-nonabelianization map), introduced by Neitzke and Yan, is a map from UV line defects in a 4d N=2 theory of class S to those of the IR. Mathematically, it can be described as a map between skein […]

  • Quantization of causal diamonds in 2+1 dimensional gravity

    https://youtu.be/TOfxA6N0Eds General Relativity Seminar Speaker: Rodrigo Silva, University of Maryland Title: Quantization of causal diamonds in 2+1 dimensional gravity Abstract: We develop the reduced phase space quantization of causal diamonds in $2+1$ dimensional gravity with a nonpositive cosmological constant. The system is defined as the domain of dependence of a spacelike topological disk with a […]

  • CMSA Q and A Seminar 9/19/2023

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

    Speakers: Dan Freed (Harvard Math and CMSA), Denis Auroux (Harvard Math)

  • Exact Results in Flat Band Hubbard Models

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

    https://youtu.be/VDOvgjk_vVY Topological Quantum Matter Seminar Speaker: Jonah Herzog-Arbeitman, Princeton University Title: Exact Results in Flat Band Hubbard Models Abstract: Flat bands, like those in the kagome lattice or twisted bilayer graphene, are a natural setting for studying strongly coupled physics since the interaction strength is the only energy scale in the problem. They can exhibit unconventional behavior in the multi-orbital […]

  • The TinyStories Dataset: How Small Can Language Models Be And Still Speak Coherent

    Virtual

    https://youtu.be/wTQH6mRDXhw New Technologies in Mathematics Seminar Speaker: Ronen Eldan, Microsoft Research Title: The TinyStories Dataset: How Small Can Language Models Be And Still Speak Coherent Abstract: While generative language models exhibit powerful capabilities at large scale, when either the model or the number of training steps is too small, they struggle to produce coherent and fluent […]