Black Hole Berry Phase

TL;DR

This paper explores the theoretical phenomenon of Berry's phase in supersymmetric black holes, demonstrating how quantum microstates mix under moduli variations, with an explicit example in 5D black holes.

Contribution

It introduces the concept of Berry's phase in black hole microstates and provides a computable example in five-dimensional supersymmetric black holes.

Findings

Berry's phase causes microstate mixing under moduli changes

Explicit calculation for 5D supersymmetric black holes

Potential to probe black hole microstates theoretically

Abstract

Supersymmetric black holes are characterized by a large number of degenerate ground states. We argue that these black holes, like other quantum mechanical systems with such a degeneracy, are subject to a phenomenon which is called the geometric or Berry's phase: under adiabatic variations of the background values of the supergravity moduli, the quantum microstates of the black hole mix among themselves. We present a simple example where this mixing is exactly computable, that of small supersymmetric black holes in 5 dimensions. While in practice it would be extremely difficult to measure Berry's phase for black holes, it may be interesting to explore it further from a theoretical point of view, as it provides us with a way to probe, and to some degree manipulate, the quantum microstate of the black hole.