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Instanton in Lattice QCD from Higher Categories and Higher Anafunctors

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

Speaker: Jing-Yuan Chen, Tsinghua University Title: Instanton in Lattice QCD from Higher Categories and Higher Anafunctors Abstract:  Putting continuum QFT (not just TQFT) on the lattice is important for both fundamental understandings and practical numerics. The traditional way of doing so, based on simple intuitions, however, does not admit natural definitions for general topological operators of continuous-valued […]

Classification and Construction of crystalline topological superconductors and insulators in interacting fermion systems

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

Quantum Matter Seminar Speaker: Zhengcheng Gu, Chinese University of Hong Kong Title: Classification and construction of crystalline topological superconductors and insulators in interacting fermion systems Abstract: The construction and classification of crystalline symmetry protected topological (SPT) phases in interacting bosonic and fermionic systems have been intensively studied in the past few years. Crystalline SPT phases […]

Going to the other side …. in algebra, topology, and maybe physics

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

Quantum Field Theory and Physical Mathematics Speaker: Sergei Gukov (Caltech) Title: Going to the other side .... in algebra, topology, and maybe physics Abstract: Inspired by Eugene Wigner's reflections on the 'unreasonable effectiveness of mathematics in the natural sciences,' this talk is about the surprising and pervasive role of a peculiar phenomenon that, a priori, […]

Holography and Regge Phases at Large U(1) Charge

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

Quantum Field Theory and Physical Mathematics Seminar Speaker: Giulia Fardelli, Boston University Title: Holography and Regge Phases at Large U(1) Charge Abstract: A single Conformal Field Theory (CFT) can have a rich phase diagram with qualitatively different emergent behaviors in a range of different regimes parameterized by the conserved charges of the theory. In this […]

Dolbeault Virasoro algebra and M5 branes

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

Quantum Field Theory and Physical Mathematics Seminar Speaker: Brian Williams, Boston University Title: Dolbeault Virasoro algebra and M5 branes Abstract: The worldvolume theory on a stack of M5 branes in M-theory is superconformal. We propose a conjecture that in the holomorphic twist of the theory on a stack of M5 branes an infinite-dimensional enhancement of […]

Bosonic and fermionic 1-form symmetries and anomaly matching

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

Quantum Field Theory and Physical Mathematics Seminar *via Zoom only* Speaker: Rajath Radhakrishnan (ICTP, Trieste) Title: Bosonic and fermionic 1-form symmetries and anomaly matching Abstract: In this talk, I will consider bosonic and fermionic (non-invertible) 1-form symmetries in 2+1d QFTs. These are 1-form symmetries implemented by topological line operators with real spins. I will present a classification […]

The spin-statistics theorem for TFTs

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

Quantum Field Theory and Physical Mathematics Seminar Speaker: Luuk Stehouwer, Dalhousie University Title: The spin-statistics theorem for TFTs Abstract: In quantum field theory (QFT) the spin-statistics theorem says that in a unitary QFT, a particle has half-integer spin if and only if it is a fermion. I show how to phrase this statement in the […]

Representations of minimal W-algebras: unitarity and modular invariance

Virtual

Quantum Field Theory and Physical Mathematics Seminar Speaker: Victor Kac (MIT) Title: Representations of minimal W-algebras: unitarity and modular invariance Abstract: The minimal W-algebras, obtained by quantum Hamiltonian reduction from affina vertex algebras, form the most interesting class of vertex algebras, which includes all superconformal algebras: Virasoro, Neveu-Scharz, N=2, 3, 4, and big N=4. I will […]