Seminar
Speaker
Nissan Itzhaki (Tel Aviv University, Israel)
Date & Time
Wed, 01 December 2021, 15:00 to 16:30
Venue
Online Seminar
Abstract

We consider the backreaction of the winding zero mode on the cigar geometry. We focus on the case of the $SL(2,R)_k/U(1)$ cigar associated with e.g. the near-horizon limit of $k$ NS5 black-branes. We solve the equations of motion numerically in the large $k$ limit as a function of the amplitude of the winding mode at infinity. We find that there is a critical amplitude $C_c=\exp(-\gamma/2)$ that admits a critical solution. The exact CFT description of the $SL(2,R)_k/U(1)$ cigar, in particular the FZZ duality, fixes completely the winding amplitude. We find that in the large $k$ limit there is an exact agreement $C_c=C_{FZZ}$. The critical solution is a cigar with a puncture at its tip; consequently, the BH entropy is carried entirely by the winding condensate. We argue that, in the Lorentzian case, the information is ejected from the black hole through this puncture.