118 research outputs found
Supergravity Solutions for Localized Intersections of Branes
We construct an explicit supergravity solution for a configuration of
localized D4-brane ending on a D6-brane, restricted to the near horizon region
of the latter. We generate this solution by dimensionally reducing the
supergravity solution for a flat M5-brane in with the
M5-brane partially embedded in . We describe the general class of
localized intersections and overlaps whose supergravity solutions are
constructible in this way.Comment: 15 pages, 1 figur
On the Hierarchy Between Non-Commutative and Ordinary Supersymmetric Yang-Mills
Non-commutative supersymmetric Yang-Mills with rational Theta is dual to an
ordinary supersymmetric Yang-Mills with a 't Hooft flux. It is believed that
the simplest description is via the ordinary supersymmetric Yang-Mills. We
claim, however, that the two descriptions form a hierarchy. The SYM description
is the proper description in the ultra violet while the non-commutative
description takes over in the infra red.Comment: 16 pages, 3 figures, references adde
Perturbative Dynamics of Fractional Strings on Multiply Wound D-strings
Fractional strings in the spectrum of states of open strings attached to a
multiply wound D-brane is explained. We first describe the fractional string
states in the low-energy effective theory where the topology of multiple
winding is encoded in the gauge holonomy. The holonomy induces twisted boundary
conditions responsible for the fractional moding of these states. We also
describe fractional strings in world sheet formulation and compute simple
scattering amplitudes for Hawking emission/absorption. Generalization to
fractional DN-strings in a 1-brane 5-brane bound state is described. When a
1-brane and a 5-brane wraps and times respectively around a circle,
the momentum of DN-strings is quantized in units of . These
fractional states appear naturally in the perturbative spectrum of the theory.Comment: 14 pages, LaTeX, 3 figure
Matrix Model Approach to Non-critical Superstrings
We apply light-cone quantization to a dimensional supersymmetric field
theory of large N matrices. We provide some preliminary numerical evidence that
when the coupling constant is tuned to a critical value, this model describes a
2+1 dimensional non-critical superstring.Comment: 11 pages, 3 Encapsulated Postscript figures. uses psfig.sty
(available from http://xxx.lanl.gov/ftp/hep-th/papers/macros
Large branes in AdS and their field theory dual
Recently it was suggested that a graviton in with a large
momentum along the sphere can blow up into a spherical D-brane in . In
this paper we show that the same graviton can also blow up into a spherical
D-brane in with exactly the same quantum numbers (angular momentum and
energy). These branes are BPS, preserving 16 of the 32 supersymmetries. We show
that there is a BPS {\it classical} solution for SYM on with
exactly the same quantum numbers. The solution has non-vanishing Higgs
expectation values and hence is dual to the large brane in AdS.Comment: 20 pages, 6 figures, minor change
Dynamics of supersymmetric field theories in 2+1 dimensions and their gravity dual
In this note we consider SYM theories in 2+1 dimensions with
gauge group and hypermultiplets charged under the .
When , the theory flows to a superconformal fixed point in the IR.
Theories with , on the other hand, flows to strong coupling. We
explore these theories from the perspective of gravity dual. We find that the
gravity duals of theories with contain enhancons even in situations
where repulson singularities are absent. We argue that supergravity description
is unreliable in the region near these enhancon points. Instead, we show how to
construct reliable sugra duals to particular points on the Coulomb branch where
the enhancon is screened. We explore how these singularities reappear as one
moves around in Coulomb branch and comment on possible field theory
interpretation of this phenomenon. In analyzing gauge/gravity duality for these
models, we encountered one unexpected surprise, that the condition for the
supergravity solution to be reliable and supersymmetric is somewhat weaker than
the expectation from field theory. We also discuss similar issues for theories
with .Comment: 31 pages, 12 figure
- …