Related papers: Penrose limits, supergravity and brane dynamics
We consider two possible flat space limits of three dimensional $\mathcal{N} = (1,1)$ AdS supergravity. They differ by how the supercharges are scaled with the AdS radius $\ell$: the first limit (democratic) leads to the usual…
BPS configurations of intersecting branes have many applications in string theory. We attempt to provide an introductory and pedagogical review of supergravity solutions corresponding to orthogonal BPS intersections of branes with an…
We study the properties of half-supersymmetric branes in string theory with 32 supercharges from a purely group-theoretical point of view using the U-duality symmetry of maximal supergravity and the R-symmetry of the corresponding…
We use the inverse mean curvature flow to establish Penrose-type inequalities for time-symmetric Einstein-Maxwell initial data sets which can be suitably embedded as a hypersurface in Euclidean space $\mathbb R^{n+1}$, $n\geq 3$. In…
The Penrose inequality gives a lower bound for the total mass of a spacetime in terms of the area of suitable surfaces that represent black holes. Its validity is supported by the cosmic censorship conjecture and therefore its proof (or…
We develop the concept of supersymmetry in singular spaces, apply it in an example for 3-branes in D=5 and comment on 8-branes in D=10. The new construction has an interpretation that the brane is a sink for the flux and requires adding to…
We review the recent developments in superstrings. We start with a brief summary of various consistent superstring theories and discuss T-duality which necessarily leads to the presence of D-branes. The properties of D-branes are summarized…
In three dimensions, a theory with spontaneous breaking of supersymmetry was described holographically by the Maldacena-Nastase (MNa) solution. We revisit the issue of its Penrose limit, and compare the resulting pp wave and its string…
Eleven-dimensional supergravity has a non-relativistic variant obtained by taking a limit associated with the M2 brane. Consistency of this non-relativistic supergravity requires constraints. There is one choice of constraints which keeps…
In this paper we study the Penrose limit of AdS_5 orbifolds. The orbifold can be either in the pure spatial directions or space and time directions. For the AdS_5/\Gamma\times S^5 spatial orbifold we observe that after the Penrose limit we…
With one exception, all known non-supersymmetric AdS$_4$ and AdS$_5$ vacua of gauged maximal supergravities that descend from string and M theory have been shown to have modes with mass below the BF bound. The remaining non-supersymmetric…
We give an overview of various composite BPS configurations of string theory and M-theory p-branes represented as classical supergravity solutions. Type II string backgrounds can be obtained by S- and T- dualities from NS-NS string -…
In this paper we explore some general aspects of the embeddings associated with brane-localized gravity. In particular we show that the consistency of such embeddings can require (or impose) very specific relations between all the involved…
We construct an intersecting S-brane solution of 11-dimensional supergravity for which the contribution of the Chern-Simons term to the field equations is non-zero. After studying some of its properties, we consider three different…
We study little string theory on R^1 x S^5, defined by a theory which lives on type IIA N NS5 branes wrapped on S^5, using its supergravity dual. In particular we study semiclassical rotating closed strings in this background. We also…
We investigate the brane models in arbitrary dimensional critical gravity presented in [Phys. Rev. Lett. 106, 181302 (2011)]. For the model of the thin branes with codimension one, the Gibbons-Hawking surface term and the junction…
It is known that certain AdS boundary conditions allow smooth initial data to evolve into a big crunch. To study this type of cosmological singularity, one can use the dual quantum field theory, where the non-standard boundary conditions…
What happens at spacetime singularities is poorly understood. The Penrose-Wall singularity theorem constrains possible scenarios, but until recently its key assumption--the generalized second law (GSL)--had only been proven perturbatively,…
We use branes to generalize the Distance Conjecture. We conjecture that in any infinite-distance limit in the moduli space of a $d$-dimensional quantum gravity theory, among the set of particle towers and fundamental branes with at most…
We find all symmetric space solutions of eleven-dimensional supergravity completing an earlier classification by Figueroa-O'Farrill. They come in two types: AdS solutions and pp-wave solutions. We analyze the supersymmetry conditions and…