1,076 research outputs found
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
Black Rings in Taub-NUT
We construct the most generic three-charge, three-dipole-charge, BPS
black-ring solutions in a Taub-NUT background. These solutions depend on seven
charges and six moduli, and interpolate between a four-dimensional black hole
and a five-dimensional black ring. They are also instrumental in determining
the correct microscopic description of the five-dimensional BPS black rings.Comment: 16 pages, harvma
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
Bubbles on Manifolds with a U(1) Isometry
We investigate the construction of five-dimensional, three-charge
supergravity solutions that only have a rotational U(1) isometry. We show that
such solutions can be obtained as warped compactifications with a singular
ambi-polar hyper-Kahler base space and singular warp factors. We show that the
complete solution is regular around the critical surface of the ambi-polar
base. We illustrate this by presenting the explicit form of the most general
supersymmetric solutions that can be obtained from an Atiyah-Hitchin base space
and its ambi-polar generalizations. We make a parallel analysis using an
ambi-polar generalization of the Eguchi-Hanson base space metric. We also show
how the bubbling procedure applied to the ambi-polar Eguchi-Hanson metric can
convert it to a global AdS_2xS^3 compactification.Comment: 33 pages, 5 figures, LaTeX; references adde
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
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
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
Three-Form Flux with N=2 Supersymmetry on AdS_5 x S^5
In the context of the AdS/CFT correspondence the general form of a three-form
flux perturbation to the AdS_5 x S^5 solution in the type IIB supergravity
which preserves N=2 supersymmetry is obtained. The arbitrary holomorphic
function appearing in the N=1 case studied by Grana and Polchinski is
restricted to a quadratic function of the coordinates transverse to the
D3-branes.Comment: 11 pages, LaTe
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