868 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
Three-charge 2J black ring
Using recently proposed new solution generating technique, we construct the
charged version of Pomeranski-Senkov doubly rotating black ring in the
five-dimensional supergravity. For arbitrary values of charges the solution is
unbalanced, but the Dirac-Misner string is removed when two of the charges are
set to zero. In this particular case our solution can be uplifted to some
solution of six-dimensional vacuum gravity.Comment: 9 pages revtex
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
Effects of decoherence on the shot noise in carbon nanotubes
We study the zero frequency noise in an interacting quantum wire connected to
leads, in the presence of an impurity. In the absence of quasiparticle
decoherence the zero-frequency noise is that of a non-interacting wire.
However, if the collective, fractionally-charged modes have a finite lifetime,
we find that the zero-frequency noise may still exhibit signatures of charge
fractionalization, such as a small but detectable reduction of the ratio
between the noise and the backscattered current (Fano factor). We argue that
this small reduction of the Fano factor is consistent with recent observations
of a large reduction in the experimentally-inferred Fano factor in nanotubes
(calculated assuming that the backscattered current is the difference between
the ideal current in a multiple-channel non-interacting wire and the measured
current.Comment: 6 pages, 1 figur
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
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
Multi-Centered Black Hole Flows
We describe the systematical construction of the first order formalism for
multi-centered black holes with flat three dimensional base-space, within the
so-called model of N=2, D=4 ungauged Maxwell-Einstein supergravity. The
three possible flow classes (BPS, composite non-BPS and almost-BPS) are
analyzed in detail, and various solutions, such as single-centered (static or
under-rotating) and all known multi-centered black holes, are recovered in this
unified framework. We also consider the possibility of obtaining new solutions.
The almost-BPS class is proved to split into two general sub-classes,
corresponding to a positive or negative value of the duality-invariant
polynomial for the total charge; the well known almost BPS system is shown to
be a particular solution of the second sub-class.Comment: 17 pages,no figure
On Metastable Vacua and the Warped Deformed Conifold: Analytic Results
Continuing the programme of constructing the backreacted solution
corresponding to smeared anti-D3 branes in the warped deformed conifold, we
solve analytically the equations governing the space of first-order
deformations around this solution. We express the results in terms of at most
three nested integrals. These are the simplest expressions for the space of
SU(2) \times SU(2) \times \ZZ_2-invariant deformations, in which the putative
solution for smeared anti-D3 branes must live. We also explain why one cannot
claim to identify this solution without fully relating the coefficients of the
infrared and ultraviolet expansions of the deformation modes. The analytic
solution we find is the first step in this direction.Comment: 16 page
Multi-Center non-BPS Black Holes - the Solution
We construct multi-center, non-supersymmetric four-dimensional solutions
describing a rotating anti-D6-D2 black hole and an arbitrary number of D4-D2-D0
black holes in a line. These solutions correspond to an arbitrary number of
extremal non-BPS black rings in a Taub-NUT space with a rotating three-charge
black hole in the middle. The positions of the centers are determined by
solving a set of "bubble" or "integrability" equations that contain cubic
polynomials of the inter-center distance, and that allow scaling solutions even
when the total four-dimensional angular momentum of the scaling centers is
non-zero.Comment: 16 pages, LaTe
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