Physics

Four-dimensional superconformal field theories can be studied and partially classified by compactifying six-dimensional ones on punctured Riemann surfaces. In this talk we discuss the holographic dual of this set-up and explore how various...

The multiscale entanglement renormalization ansatz (MERA) is a tensor network that can efficiently approximate ground states of critical spin chains --that is, lattice versions of 1+1 CFTs. Its network structure extends in an additional dimension...

Recent lattice results on $\theta$ at high temperatures call into question the standard semiclassical analysis of $\theta$-dependence at high temperatures. We examine arguments that there are large uncertainties in these computations, studying both...

Quantum field theories can have ordinary global symmetries, as well as generalized higher-form symmetries. 2-group symmetries arise when a generalized 1-form symmetry mixes with ordinary global symmetries. I will discuss theories with continuous 2...

Global symmetries in two dimensions are implemented by topological defect lines (TDLs). For continuous global symmetries, the TDLs are nothing but the Noether charges. However, there are TDLs that are not associated to any global symmetry, and can...

I will explore the generalization of the Feynman path integral in quantum field theory to complexified fields, and explain how it can be utilized to tackle the famous "sign problem". The sign problem prevents first principle studies of real-time...

The paradigmatic example of $AdS_4/CFT_3$ relates M-theory on $AdS_4 x S^7$ to the family of maximally supersymmetric 3d CFTs discovered by Aharony, Bergman, Jafferis, and Maldacena (ABJM). I will focus on the stress tensor four point function for...

In finite entropy systems such as black holes, real-time partition functions do not decay to zero at late times. It is a challenge to derive this non-decaying behavior starting from the path integral over the master fields of a large N theory. I...

It has been recently recognized that the same type of melonic large N structure governs SYK models and tensor models alike. Following Witten and Klebanov-Tarnopolsky, this has led to the introduction of new SYK-like tensor models, which reproduce...