Multipartitioning topological phases and quantum entanglement
Speaker: Shinsei Ryu (Princeton University) Title: Multipartitioning topological phases and quantum entanglement Abstract: We discuss multipartitions of the gapped ground states of (2+1)-dimensional topological liquids into three (or more) spatial regions that are adjacent to each other and meet at points. By considering the reduced density matrix obtained by tracing over a subset of the regions, we […]
Exact Eigenstates in Non-Integrable Systems: A violation of the ETH
Speaker: B. Andrei Bernevig (Princeton University) Title: Exact Eigenstates in Non-Integrable Systems: A violation of the ETH Abstract: We find that several non-integrable systems exhibit some exact eigenstates that span the energy spectrum from lowest to the highest state. In the AKLT Hamiltonian and in several others “special” non-integrable models, we are able to obtain the analytic […]
Quantum Geometric Aspects of Chiral Twisted Graphene Models
Speaker: Jie Wang (Simons Foundation) Title: Quantum Geometric Aspects of Chiral Twisted Graphene Models Abstract: “Moire” materials produced by stacking monolayers with small relative twist angles are of intense current interest for the range of correlated electron phenomena they exhibit. The quench of the kinetic energy means that the interacting physics is controlled by the interplay between […]
A degeneracy bound for homogeneous topological order
Speaker: Jeongwan Haah (Microsoft) Title: A degeneracy bound for homogeneous topological order https://www.youtube.com/watch?v=IjHJa-hy-3o
Non-Invertible Duality Defects in 3+1 Dimensions
Speaker: Clay Cordova (U Chicago) Title: Non-Invertible Duality Defects in 3+1 Dimensions Abstract: For any quantum system invariant under gauging a higher-form global symmetry, we construct a non-invertible topological defect by gauging in only half of spacetime. This generalizes the Kramers-Wannier duality line in 1+1 dimensions to higher spacetime dimensions. We focus on the case of a […]
Anomaly resolution via decomposition
Speaker: Eric Sharpe (Virginia Tech) Title: Anomaly resolution via decomposition Abstract: In this talk we will discuss a method of anomaly resolution due to Wang-Wen-Witten in the special case of (1+1) dimensional theories. Briefly, for our purposes, Wang-Wen-Witten argued that an ill-defined anomalous orbifold could be resolved by extending G to a larger group and […]
Electric-magnetic duality and the Geometric Langlands duality
Title: Electric-magnetic duality and the Geometric Langlands duality Abstract: I will give a pedagogical review of the connection between electric-magnetic duality and the Geometric Langlands duality.
Categorification and applications
Speaker: Peng Shan (Tsinghua University) Title: Categorification and applications Abstract: I will give a survey of the program of categorification for quantum groups, some of its recent development and applications to representation theory.
D3C: Reducing the Price of Anarchy in Multi-Agent Learning
Speaker: Ian Gemp, DeepMind Title: D3C: Reducing the Price of Anarchy in Multi-Agent Learning Abstract: In multi-agent systems the complex interaction of fixed incentives can lead agents to outcomes that are poor (inefficient) not only for the group but also for each individual agent. Price of anarchy is a technical game theoretic definition introduced to quantify the […]
A tour of categorical symmetry
Title: A tour of categorical symmetry Abstract: I will discuss some perspectives on symmetry coming from the study of topological defects in quantum field theory. I will argue that we should take topological defects themselves to define the symmetries of QFT. This gives us a view of the “category of QFTs”. I will describe some […]
Line defects in CFTs: Renormalization group flows and semiclassical limits
Title: Line defects in CFTs: Renormalization group flows and semiclassical limits Abstract: I will discuss line defects in d-dimensional Conformal Field Theories (CFTs). In the first part of the talk, I will argue that the ambient CFT places nontrivial constraints on Renormalization Group (RG) flows on such line defects. I will show that the flow […]