40 research outputs found
Supersymmetric Charged Clouds in AdS_5
We consider supersymmetric holographic flows that involve background gauge
fields dual to chemical potentials in the boundary field theory. We use a
consistent truncation of gauged N=8 supergravity in five dimensions and we give
a complete analysis of the supersymmetry conditions for a large family of
flows. We examine how the well-known supersymmetric flow between two fixed
points is modified by the presence of the chemical potentials and this yields a
new, completely smooth, solution that interpolates between two global AdS
spaces of different radii and with different values of the chemical potential.
We also examine some black-hole-like singular flows and a new
non-supersymmetric black hole solution. We comment on the interpretation of our
new solutions in terms of giant gravitons and discuss the implications of our
work for finding black-hole solutions in AdS geometries.Comment: 31 pages, 6 figures; minor corrections, updated reference
Consistent SO(6) Reduction Of Type IIB Supergravity on S^5
Type IIB supergravity can be consistently truncated to the metric and the
self-dual 5-form. We obtain the complete non-linear Kaluza-Klein S^5 reduction
Ansatz for this theory, giving rise to gravity coupled to the fifteen
Yang-Mills gauge fields of SO(6) and the twenty scalars of the coset
SL(6,R)/SO(6). This provides a consistent embedding of this subsector of N=8,
D=5 gauged supergravity in type IIB in D=10. We demonstrate that the
self-duality of the 5-form plays a crucial role in the consistency of the
reduction. We also discuss certain necessary conditions for a theory of gravity
and an antisymmetric tensor in an arbitrary dimension D to admit a consistent
sphere reduction, keeping all the massless fields. We find that it is only
possible for D=11, with a 4-form field, and D=10, with a 5-form. Furthermore,
in D=11 the full bosonic structure of eleven-dimensional supergravity is
required, while in D=10 the 5-form must be self-dual. It is remarkable that
just from the consistency requirement alone one would discover D=11 and type
IIB supergravities, and that D=11 is an upper bound on the dimension.Comment: Latex, 14 pages, typos corrected and comments adde
Orbifolds and Flows from Gauged Supergravity
We examine orbifolds of the IIB string via gauged supergravity. For the
gravity duals of the A_{n-1} quiver gauge theories, we extract the massless
degrees of freedom and assemble them into multiplets of N=4 gauged supergravity
in five dimensions. We examine the embedding of the gauge group into the
isometry group of the scalar manifold, as well as the symmetries of the scalar
potential. From this we find that there is a large SU(1,n) symmetry group which
relates different RG flows in the dual quiver gauge theory. We find that this
symmetry implies an extension of the usual duality between ten-dimensional IIB
solutions which involves exchanging geometric moduli with background fluxes.Comment: 37 pages, harvma
Consistent truncation of d = 11 supergravity on AdS_4 x S^7
We study the system of equations derived twenty five years ago by B. de Wit
and the first author [Nucl. Phys. B281 (1987) 211] as conditions for the
consistent truncation of eleven-dimensional supergravity on AdS_4 x S^7 to
gauged N = 8 supergravity in four dimensions. By exploiting the E_7(7)
symmetry, we determine the most general solution to this system at each point
on the coset space E_7(7)/SU(8). We show that invariants of the general
solution are given by the fluxes in eleven-dimensional supergravity. This
allows us to both clarify the explicit non-linear ansatze for the fluxes given
previously and to fill a gap in the original proof of the consistent
truncation. These results are illustrated with several examples.Comment: 41 pages, typos corrected, published versio
Collapsing Perfect Fluid in Higher Dimensional Spherical Spacetimes
The general metric for N-dimensional spherically symmetric and conformally
flat spacetimes is given, and all the homogeneous and isotropic solutions for a
perfect fluid with the equation of state are found. These
solutions are then used to model the gravitational collapse of a compact ball.
It is found that when the collapse has continuous self-similarity, the
formation of black holes always starts with zero mass, and when the collapse
has no such a symmetry, the formation of black holes always starts with a mass
gap.Comment: Class. Quantum Grav. 17 (2000) 2589-259
Constructing Lifshitz solutions from AdS
Under general assumptions, we show that a gravitational theory in d+1
dimensions admitting an AdS solution can be reduced to a d-dimensional theory
containing a Lifshitz solution with dynamical exponent z=2. Working in a d=4,
N=2 supergravity setup, we prove that if the AdS background is N=2
supersymmetric, then the Lifshitz geometry preserves 1/4 of the supercharges,
and we construct the corresponding Killing spinors. We illustrate these results
in examples from supersymmetric consistent truncations of type IIB
supergravity, enhancing the class of known 4-dimensional Lifshitz solutions of
string theory. As a byproduct, we find a new AdS4 x S1 x T(1,1) solution of
type IIB.Comment: 29 pages, no figures; v2 minor corrections, a reference adde
AdS vacua and RG flows in three dimensional gauged supergravities
We study supersymmetric vacua in N=4 and N=8, three dimensional
gauged supergravities, with scalar manifolds and , non-semisimple Chern-Simons
gaugings and ,
respectively. These are in turn equivalent to SO(4) and
Yang-Mills theories coupled to supergravity. For the N=4 case, we study
renormalization group flows between UV and IR vacua with the same
amount of supersymmetry: in one case, with (3,1) supersymmetry, we can find an
analytic solution whereas in another, with (2,0) supersymmetry, we give a
numerical solution. In both cases, the flows turn out to be v.e.v. flows, i.e.
they are driven by the expectation value of a relevant operator in the dual
. These provide examples of v.e.v. flows between two vacua
within a gauged supergravity framework.Comment: 35 pages in JHEP form, 3 figures, typos corrected, references adde
Non-conformal examples of AdS/CFT
Asymptotically anti-de Sitter spacetimes with Poincare invariance along the
boundary can describe, via the AdS/CFT correspondence, either relevant
deformations of a conformal field theory or non-conformal vacuum states. I
consider examples of both types constructed in the framework of
five-dimensional gauged supergravity. I explain the proof and motivation of a
gravitational ``c-theorem'' which is independent of dimension. I show how one
class of examples can be elevated to ten-dimensional geometries involving
distributions of parallel D3-branes. For these cases some peculiar properties
of two-point functions emerge, and I close with speculations on their physical
origin.Comment: 16 pages, two figures, latex. Strings '99 tal
New Results on Holographic Three-Point Functions
We exploit a gauge invariant approach for the analysis of the equations
governing the dynamics of active scalar fluctuations coupled to the
fluctuations of the metric along holographic RG flows. In the present approach,
a second order ODE for the active scalar emerges rather simply and makes it
possible to use the Green's function method to deal with (quadratic)
interaction terms. We thus fill a gap for active scalar operators, whose
three-point functions have been inaccessible so far, and derive a general,
explicitly Bose symmetric formula thereof. As an application we compute the
relevant three-point function along the GPPZ flow and extract the irreducible
trilinear couplings of the corresponding superglueballs by amputating the
external legs on-shell.Comment: v2: reference added, typos corrected v3: sign convention for
background changed, agrees with version published in JHE
Renormalization Group Flows from Five-Dimensional Supergravity
The use of gauged supergravity as a tool in studying the
AdS/CFT correspondence for Yang-Mills theory is reviewed. The
supergravity potential implies a non-trivial, supersymmetric IR fixed point,
and the flow to this fixed point is described in terms of a supergravity kink.
The results agree perfectly with earlier, independent field theory results. A
supergravity inspired -function, and corresponding -theorem is discussed
for general flows, and the simplified form for supersymmetric flows is also
given. Flows along the Coulomb branch of the Yang-Mills theory are also
described from the five-dimensional perspective.Comment: 12 pages, 3 figures; Latex, ioplppt.sty, iopl12.sty, epsf.sty.
Contribution to Strings `9