Superstars and Giant Gravitons

TL;DR

The paper addresses naked singularities in BPS AdS$_5\times S^5$ supergravity solutions carrying internal momentum. By lifting to ten dimensions, it shows a strong RR five-form dipole signals a distribution of spherical D3-branes (giant gravitons) on $S^5$, and computes the precise density that accounts for all internal momentum, matching the supergravity mass via BPS relations. Probing with dual giant gravitons reveals no universal expansion into AdS directions that would resolve the singularity, though certain charged cases exhibit finite-radius minima. These results bolster the giant-graviton interpretation of the singularities, illuminate the AdS/CFT dictionary for momentum-carrying branes, and open avenues to study backreaction, smeared momentum states, and extensions to other dimensions.

Abstract

We examine a family of BPS solutions of ten-dimensional type IIb supergravity. These solutions asymptotically approach AdS_5 X S^5 and carry internal `angular' momentum on the five-sphere. While a naked singularity appears at the center of the anti-de Sitter space, we show that it has a natural physical interpretation in terms of a collection of giant gravitons. We calculate the distribution of giant gravitons from the dipole field induced in the Ramond-Ramond five-form, and show that these sources account for the entire internal momentum carried by the BPS solutions.