Iosif Bena
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Localized black holes in AdS3: what happens below $$ \frac{c}{12} $$ stays below $$ \frac{c}{12} $$ Open
A bstract We construct asymptotically AdS 3 ×S 3 ×T 4 black holes that are localized on the S 3 and co-exist with the BTZ black hole at small positive energies. These black holes dominate the microcanonical ensemble for E ≤ $$ \frac{c}{24}…
Positive Spin-induced Quadrupole Moment in String Theory Open
We identify singularity-free Running-Kerr-Taub-Bolt solutions of eleven-dimensional supergravity that descend to four-dimensional rotating solutions with flat-space asymptotics. We compute their spin-induced quadrupole moment and find that…
The M2-M5 Mohawk Open
A bstract We show that the near-brane back-reaction of M2 branes ending on M5 branes has a rich “spike structure” that is determined by partitioning the numbers of M2 branes that are terminating on groups of M5 branes. The near-brane limit…
Microstate Geometries Open
We review the 20-year history of the Microstate Geometry Programme and the essential role that supergravity has played, and will continue to play, in the description of black-hole microstructure.
Maze topiary in supergravity Open
A bstract We show that the supergravity solutions for $$ \frac{1}{4} $$ -BPS intersecting systems of M2 and M5 branes are completely characterized by a single “maze” function that satisfies a non-linear “maze” equation similar to the Monge…
Waves on mazes Open
A bstract One way to describe the entropy of black holes comes from partitioning momentum charge across fractionated intersecting brane systems. Here we construct $$ \frac{1}{8} $$ -BPS solutions by adding momentum to a maze of M2-brane st…
Localized Black Holes in AdS$_3$: What Happens Below c/12 Stays Below c/12 Open
We construct asymptotically AdS$_3 \times$S$^3 \times$T$^4$ black holes that are localized on the S$^3$ and co-exist with the BTZ black hole at small positive energies. These black holes dominate the microcanonical ensemble for $ E\leq \fr…
KKLT Ex Nihilo Open
Flux compactifications that give three- or four-dimensional Anti de Sitter vacua with a parametrically small negative cosmological constant are claimed to be ubiquitous in String Theory. However, the 1+1 and 2+1 dimensional CFT duals to su…
On the supersymmetries of branes with fluxes Open
The Dirac-Born-Infled action that describes the dynamics of D branes also allows one to compute the supersymmetries they preserve using the Kappa-symmetry projector. The ''Lagrangian'' expression of this projector depends on the velocity a…
The M2-M5 Mohawk Open
We show that the near-brane back-reaction of M2 branes ending on M5 branes has a rich "spike structure" that is determined by partitioning the numbers of M2 branes that are terminating on groups of M5 branes. The near-brane limit of the me…
Born-Infeld supermaze waves Open
A bstract The entropy of the supersymmetric D2-D4-P black hole comes at weak coupling from D2-brane strips stretched between parallel D4 branes and carrying momentum waves. We use the DBI action of D4 branes to construct two pieces of plum…
Waves on Mazes Open
One way to describe the entropy of black holes comes from partitioning momentum charge across fractionated intersecting brane systems. Here we construct $\frac{1}{8}$-BPS solutions by adding momentum to a maze of M2-brane strips stretched …
Born-Infeld Supermaze Waves Open
The entropy of the supersymmetric D2-D4-P black hole comes at weak coupling from D2-brane strips stretched between parallel D4 branes and carrying momentum waves. We use the DBI action of D4 branes to construct two pieces of plumbing that …
Maze Topiary in Supergravity Open
We show that the supergravity solutions for 1/4-BPS intersecting systems of M2 and M5 branes are completely characterized by a single ``maze'' function that satisfies a non-linear ``maze'' equation similar to the Monge-Ampère equation. We …
Bare-bones de Sitter vacua Open
We compute the supersymmetry-breaking three-form fluxes generated by the addition of anti-D3 branes at the tip of a Klebanov-Strassler throat. These fluxes give rise to nontrivial terms in the superpotential when the throat is embedded in …
Brane-jet instabilities Open
With one exception, all known non-supersymmetric AdS4and AdS5vacua of gauged maximal supergravities that descend from string and M theory have been shown to have modes with mass below the BF bound. The remaining non-supersymmetric AdS solu…
Delaying the inevitable: tidal disruption in microstate geometries Open
Microstate geometries in string theory replace the black-hole horizon with a smooth geometric “cap” at the horizon scale. In geometries constructed using superstratum technology, this cap has the somewhat surprising property that induces v…
Early scrambling and capped BTZ geometries Open
Geodesic probes in certain horizonless microstate geometries experience extreme tidal forces long before reaching the region where these geometries differ significantl from the extremal BTZ black hole. The purpose of this paper is to show …
Integrability and black-hole microstate geometries Open
We examine some recently-constructed families of asymptotically-AdS3 × S3 supergravity solutions that have the same charges and mass as supersymmetric D1-D5- P black holes, but that cap off smoothly with no horizon. These solutions, known …
Asymptotically-flat supergravity solutions deep inside the black-hole regime Open
Here we construct an infinite family of smooth asymptotically-flat supergravity solutions that have the same charges and angular momenta as general supersymmetric D1-D5-P black holes, but have no horizon. These solutions resemble the corre…
Trustworthy de Sitter compactifications of string theory: a comprehensive review Open
We attempt to review all trustworthy and well-controlled de Sitter compactifications of string theory.
The (amazing) super-maze Open
A bstract The entropy of the three-charge NS5-F1-P black hole in Type IIA string theory comes from the breaking of N 1 F1 strings into N 1 N 5 little strings, which become independent momentum carriers. In M theory, the little strings corr…
Themelia: the irreducible microstructure of black holes Open
We argue that the fundamental "atomic objects" in string theory are themelia: extended objects that have 16 supersymmetries locally. We show that all existing smooth horizonless microstate geometries can be seen as bound states of themelia…
The Uplifton Open
Almost all proposals to construct de Sitter vacua with a small cosmological constant involve flux compactifications with stabilized moduli. These give AdS vacua, which are uplifted to de Sitter by adding antibranes in certain regions of th…
The (amazing) Super-Maze Open
The entropy of the three-charge NS5-F1-P black hole in Type IIA string theory comes from the breaking of $N_1$ F1 strings into $N_1 N_5$ little strings, which become independent momentum carriers. In M theory, the little strings correspond…
Anti D3-branes and gaugino condensation Open
Anti-D3 branes at the bottom of warped throats, commonly used to uplift the cosmological constant in String-Theory de Sitter proposals, source a plaethora of supersymmetry-breaking fluxes, that can interact nontrivially with other ingredie…