Precision Counting of Small Black Holes

TL;DR

This paper tests a theoretical proposal that higher-derivative interactions in N=2 supergravity can accurately describe the microstates of small supersymmetric black holes, using exact microscopic degeneracy calculations.

Contribution

It provides a validation of the higher-derivative correction approach for small black holes by comparing with exact BPS state counts.

Findings

The proposal matches the microscopic degeneracies for small black holes.

The black hole partition sum analysis supports the higher-derivative correction framework.

Extends previous work on black hole microstate counting.

Abstract

It has recently been proposed that a class of supersymmetric higher-derivative interactions in N=2 supergravity may encapsulate an infinite number of finite size corrections to the microscopic entropy of certain supersymmetric black holes. If this proposal is correct, it allows one to probe the string theory description of black-hole micro-states to far greater accuracy than has been possible before. We test this proposal for ``small'' black holes whose microscopic degeneracies can be computed exactly by counting the corresponding perturbative BPS states. We also study the ``black hole partition sum'' using general properties of of BPS degeneracies. This complements and extends our earlier work in hep-th/0502157