1,066 research outputs found
Regular 3-charge 4D black holes and their microscopic description
The perturbative corrections to Type-IIA String Theory
compactified on a Calabi-Yau three-fold allow the construction of regular
three-charge supersymmetric black holes in four dimensions, whose entropy
scales with the charges as .
We construct an M-theory uplift of these quantum black holes and show that they
can be interpreted as arising from three stacks of M2 branes on a conical
singularity. This in turns allow us relate them via a series of dualities to a
system of D3 branes carrying momentum and thus to give a microscopic
interpretation of their entropy.Comment: 20 pages, LaTe
Mergers and Typical Black Hole Microstates
We use mergers of microstates to obtain the first smooth horizonless
microstate solutions corresponding to a BPS three-charge black hole with a
classically large horizon area. These microstates have very long throats, that
become infinite in the classical limit; nevertheless, their curvature is
everywhere small. Having a classically-infinite throat makes these microstates
very similar to the typical microstates of this black hole. A rough CFT
analysis confirms this intuition, and indicates a possible class of dual CFT
microstates.
We also analyze the properties and the merging of microstates corresponding
to zero-entropy BPS black holes and black rings. We find that these solutions
have the same size as the horizon size of their classical counterparts, and we
examine the changes of internal structure of these microstates during mergers.Comment: 49 pages, 5 figures. v2 references adde
Non-extremal Black Hole Microstates: Fuzzballs of Fire or Fuzzballs of Fuzz ?
We construct the first family of microstate geometries of near-extremal black
holes, by placing metastable supertubes inside certain scaling supersymmetric
smooth microstate geometries. These fuzzballs differ from the classical black
hole solution macroscopically at the horizon scale, and for certain probes the
fluctuations between various fuzzballs will be visible as thermal noise far
away from the horizon. We discuss whether these fuzzballs appear to infalling
observers as fuzzballs of fuzz or as fuzzballs of fire. The existence of these
solutions suggests that the singularity of non-extremal black holes is resolved
all the way to the outer horizon and this "backwards in time" singularity
resolution can shed light on the resolution of spacelike cosmological
singularities.Comment: 34 pages, 10 figure
Exotic polarizations of D2 branes and oblique vacua of (S)YM
We investigate the oblique vacua in the perturbed 2+1 dimensional gauge
theory living on D2 branes. The string theory dual of these vacua is expected
to correspond to polarizations of the D2 branes into NS5 branes with D4 brane
charge. We perturb the gauge theory by adding fermions masses. In the
nonsupersymmetric case, we also consider the effect of slight variations of the
masses of the scalars. For certain ranges of scalar masses we find oblique
vacua.
We show that D4 charge is an essential ingredient in understanding D2 -> NS5
polarizations. We find that some of the polarization states which appear as
metastable vacua when D4 charge is not considered are in fact unstable. They
decay by acquiring D4 charge, tilting and shrinking to zero size.Comment: 15 pages, 3 figures, LaTe
The backreaction of anti-D3 branes on the Klebanov-Strassler geometry
We present the full numerical solution for the 15-dimensional space of
linearized deformations of the Klebanov-Strassler background which preserve the
SU(2) X SU(2) X Z_2 symmetries. We identify within this space the solution
corresponding to anti-D3 branes, (modulo the presence of a certain subleading
singularity in the infrared). All the 15 integration constants of this solution
are fixed in terms of the number of anti-D3 branes, and the solution differs in
the UV from the supersymmetric solution into which it is supposed to decay by a
mode corresponding to a rescaling of the field theory coordinates. Deciding
whether two solutions that differ in the UV by a rescaling mode are dual to the
same theory is involved even for supersymmetric Klebanov-Strassler solutions,
and we explain in detail some of the subtleties associated to this.Comment: 41 pages, 5 figures, LaTe
Persistent anti-brane singularities
Anti-D-branes inserted in warped throat geometries (supported by fluxes that
carry D-brane charges) develop unphysical singularities. It has been argued
that these singularities could be resolved when one goes beyond the linearized
approximation or includes the effects of brane polarization. In this paper we
consider anti-D6 branes, whose singularities have been shown to exist at the
full non-linear level, and demonstrate that there is no D8 brane polarization
that can resolve the singularity. We comment on the potential implications of
this result for the resolution of anti-D3 brane singularities in the
Klebanov-Strassler geometry.Comment: 16 pages; v2: comments added, version to appear in JHE
A Black Ring with two Angular Momenta in Taub-NUT
We use the recently-constructed explicit duality transformation that relates
a rotating anti-D6-D4-D2-D0 black hole solution to a rotating M5-M2-P black
string to construct a non-supersymmetric black ring in Taub-NUT that has two
angular momenta, as well as M2 charges and M5 dipole moments. This is the first
black ring solution that has both dipole charges and rotation along the S^2 of
the horizon, and hence can be thought of as the "Pomeransky-Senkov" version of
the M5-M2 black ring in Taub-NUT. Its physics should provide a testing ground
for the applicability of the blackfold approach to charged rotating black
branes, and should elucidate the phase space of charged dipole rings in various
backgrounds.Comment: 20 pages, LaTe
State-space Correlations and Stabilities
The state-space pair correlation functions and notion of stability of
extremal and non-extremal black holes in string theory and M-theory are
considered from the viewpoints of thermodynamic Ruppeiner geometry. From the
perspective of intrinsic Riemannian geometry, the stability properties of these
black branes are divulged from the positivity of principle minors of the
space-state metric tensor. We have explicitly analyzed the state-space
configurations for (i) the two and three charge extremal black holes, (ii) the
four and six charge non-extremal black branes, which both arise from the string
theory solutions. An extension is considered for the ---
multi-centered black branes, fractional small black branes and two charge
rotating fuzzy rings in the setup of Mathur's fuzzball configurations. The
state-space pair correlations and nature of stabilities have been investigated
for three charged bubbling black brane foams, and thereby the M-theory
solutions are brought into the present consideration. In the case of extremal
black brane configurations, we have pointed out that the ratio of diagonal
space-state correlations varies as inverse square of the chosen parameters,
while the off diagonal components vary as inverse of the chosen parameters. We
discuss the significance of this observation for the non-extremal black brane
configurations, and find similar conclusion that the state-space correlations
extenuate as the chosen parameters are increased.Comment: 35 pages, Keywords: Black Hole Physics, Higher-dimensional Black
Branes, State-space Correlations and Statistical Configurations. PACS
numbers: 04.70.-s Physics of black holes; 04.70.Bw Classical black holes;
04.70.Dy Quantum aspects of black holes, evaporation, thermodynamics;
04.50.Gh Higher-dimensional black holes, black strings, and related object
An Infinite-Dimensional Family of Black-Hole Microstate Geometries
We construct the first explicit, smooth, horizonless black-hole microstate
geometry whose moduli space is described by an arbitrary function of one
variable and is thus infinite-dimensional. This is achieved by constructing the
scalar Green function on a simple D6 anti-D6 background, and using this Green
function to obtain the fully back-reacted solution for a supertube with varying
charge density in this background. We show that this supertube can store
parametrically more entropy than in flat space, confirming the entropy
enhancement mechanism that was predicted using brane probes. We also show that
all the local properties of the fully back-reacted solution can, in fact, be
obtained using the DBI action of an appropriate brane probe. In particular, the
supergravity and the DBI analysis yield identical functional bubble equations
that govern the relative locations of the centers. This indicates that there is
a non-renormalization theorem that protects these functional equations as one
moves in moduli space. Our construction creates configurations that are beyond
the scope of recent arguments that appear to put strong limits on the entropy
that can be found in smooth supergravity solutions.Comment: 46 pages, 1 figure, LaTe
A harmonic family of dielectric flow solutions with maximal supersymmetry
We construct a new harmonic family: dielectric flow solutions with maximal
supersymmetry in eleven-dimensional supergravity. These solutions are
asymptotically AdS_4 x S^7, while in the infra-red the M2 branes are
dielectrically polarized into M5 branes. These solutions are holographically
dual to vacua of the mass deformed theory on M2 branes. They also provide an
interesting insight on the supergravity solutions sourced by giant gravitons,
allowing one to see how supergravity solves the giant graviton puzzle.Comment: 21 pages, LaTeX. reference adde
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