Physics

Abstract: The TTbar deformation is a holographic theory describing holography a finite distance in the bulk.   If this theory can be UV completed, it could be a model of nonperturbative bulk quantum gravity.  However, it seems to be a non-unitary...

Abstract: I use the method of images to derive the dilaton boundary term of the classical string action in a $Z_2$ orbifold (half space) with Neumann boundary conditions. The derivation is carried out to first order in alpha prime from the...

Abstract: In spite of tremendous progress in mean-field spin glass theory over the last forty years, “realistic” spin glass models with short-range interactions remain shrouded in mystery. I will talk about recent progress on this topic, proving a...

Abstract: We will discuss excitations with large spin and/or large particle number. For conformal theories this corresponds to investigating particular trajectories of heavy operators. 

We find trajectories with large approximate degeneracy and show...

Abstract: I will review the status of the duality between type II string theory on $AdS_3 \times S^3 \times T^4$ and a specific N=(4,4) supersymmetric 2d CFT. I will begin by reviewing the understanding of this theory from the late '90s, from the...

Abstract: We study the partition function of 3D de Sitter gravity defined as the trace over the Hilbert space obtained by quantizing Schwarzschild-de Sitter spacetime. Motivated by the correspondence with double scaled SYK, we identify the...

Abstract: A decade of work in band theory has built towards an understanding of topology that is largely based on the character theory of the space group. The (thousands of) topological materials predicted in this way provide a diverse set of...

Abstract: I will give a lightning review of results on this subject from 1988-1998 and then describe more recent developments, mostly current work in progress.  First, I will describe topological twisting of Lagrangian N=2 d=4 field theories in...

Abstract: The connection between 3d pure gravity and Chern-Simons theory has been proposed and studied for decades. In this talk, I will give a brief review of the works 2304.13650 and 2401.13900 with Scott Collier and Lorenz Eberhardt, where we...