Black Hole Giants

TL;DR

This paper explores BPS giant and dual giant configurations near a 1/16-BPS AdS_5 black hole horizon, quantizes their solutions, and identifies an angular momentum quantum number from electromagnetic waves that accounts for the black hole entropy.

Contribution

It introduces a novel analysis of BPS giants and dual giants in black hole backgrounds, revealing a missing degeneracy factor linked to electromagnetic waves on D-branes.

Findings

Quantization of solution space matches black hole entropy with a missing degeneracy factor.

Electromagnetic waves on D-branes generate additional angular momentum quantum numbers.

Turning on waves on dual giants produces 1/16-BPS states with extra angular momentum.

Abstract

We investigate giant and dual giant type BPS configurations in the near-horizon geometry of a certain 1/16-BPS AdS_5 black hole. By quantising the space of solutions we count the dual giant configurations and compare with the black hole entropy. This suggests a missing degeneracy factor which we argue comes from an angular momentum quantum number. From the D-brane world volume this arises from BPS electromagnetic waves. We study these waves in the context of giants and dual giants in the black hole near-horizon geometry. We further demonstrate that turning on waves on the world-volume of 1/8-BPS dual giants in AdS_5 x S^5 leads to 1/16-BPS states with an additional angular momentum quantum number.