Physics

A physical system is stable if its Hamiltonian is bounded below, so that we can define a positive notion of "energy" relative to the ground state. But what about the local energy density - can that be negative? I will provide an elegant derivation...

I will demonstrate presence of a vanishing momentum unstable quasi-normal mode in a certain class of asymptotically AdS black brane solutions and present the fully backreacted time evolution of the system resulting from this instability. I will...

I will describe some recent work studying proposals for computational complexity in holographic theories. I will discuss properties of the new gravitational observables and of complexity in the boundary theory.

In this talk, I will give an answer to the question “which QFT states holographically describe the emergence of semiclassical (conformal) geometry?” via a new construct in QFT: the causal density matrix. This new construct relies on the “lightcone...

In the first part of the talk, I’ll explore whether EE’s of subalgebras not organized by position space in a holographic CFT may be useful for bulk reconstruction. In particular I'll explain how the lengths of non-minimal geodesics in AdS3 conical...

Superconformal field theories placed in nontrivial background fields for the metric and the continuous global symmetries exhibit a rich web of RG flows across dimensions. I will discuss several examples of such flows and emphasize some of their...

I formulate the conformal crossing equation in a way that manifests the conformal representation theory. In this form the crossing equation can be generalized to any group. Using SU(2) as a toy model I compute solutions to the crossing equation in...

I will present the concept of a “BPS graph” (a special kind of spectral network) and illustrate its usefulness in the study of theories of class S. BPS graphs encode BPS quivers, even for higher rank and in the presence of non-full punctures, and...

I will discuss kinematic space--the space of pairs of points in a CFT. Basic objects living in kinematic space are OPE blocks--contributions to the OPE from a single conformal family. In holographic theories, OPE blocks are dual at leading order in...