Gary Horowitz's bubbles

Yesterday, Gary Horowitz was explaining, in a very interesting talk, that the black holes can catalyze the creation of bubbles of nothing in the context of closed string tachyon condensation studied by Allan Adams et al.

Recall that in the Scherk compactifications with antiperiodic fermions around a circle, a single wound closed string has a ground state that becomes tachyonic if the radius of the circle is small enough. Its condensation is a perturbative addition to Witten's non-perturbative nucleation of "bubble of nothing" - a process obtained by an analytical continuation of the Euclidean Schwarzschild black hole.

Gary showed several bubble solutions that may be connected to black hole solutions via non-supersymmetric counterparts of geometric transitions, and he conjectured that this novel process may even describe final stages of black hole evaporation. These mechanisms to resolve singularities are somewhat analogous to the picture envisioned by Eva and John.

He also mentioned a paper of Simon Ross that argues that similar bubbles may even arise in asymptotically supersymmetric background in the presence of rotating charged black holes. The possibility that these bizarre processes occur even in the stable, supersymmetric context make them even more interesting.