ITMP Seminar "Supersymmetric Grey Galaxies, Dual Dressed Black Holes and the Superconformal Index"

Dear Colleagues,

We are pleased to announce that the next ITMP seminar will be held on Wednesday, Mar 19, at 19:00 (Moscow time). It will be organised via Zoom. 

Speaker: Dr. Diksha Jain, University of Cambridge

Title: Supersymmetric Grey Galaxies, Dual Dressed Black Holes and the Superconformal Index

Abstract: In this talk, I will talk about our recent work on supersymmetric grey galaxies and dual dressed black holes in AdS^5 \times S^5. These solutions consist of a core black hole surrounded by some matter (either graviton gas or D-branes). Motivated by these solutions, we conjecture the existence of a large number of supersymmetric states for a five-parameter set of charges. We predict a microcanonical phase diagram of supersymmetric states with eleven distinct phases, and makes a sharp prediction for the supersymmetric entropy (as a function of 5 charges) in each of these phases. The microcanonical version of the superconformal index involves a sum over states - with alternating signs - over a line in 5 parameter charge space. Our second conjecture asserts that this sum is dominated by the point on the line that has the largest supersymmetric entropy. This conjecture predicts a large N formula for the superconformal index as a function of indicial charges, and predicts a microcanonical indicial phase diagram with nine distinct phases. It predicts agreement between the superconformal index and black hole entropy in one phase (so over one range of charges), but disagreement in other phases (and so at other values of charges). We compare our predictions against numerically evaluated superconformal index at N≤10, and find qualitative agreement.