Related papers: Gravitational Waves in String theory in Anti-de Si…
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…
We present details of a geometric method to associate a Lie superalgebra with a large class of bosonic supergravity vacua of the type AdS x X, corresponding to elementary branes in M-theory and type II string theory.
We show how some features of the AdS/CFT correspondence for AdS_3 can easily be understood via standard world-sheet methods and 2d gravity like scaling arguments. To do this, we propose a stringy way for perturbing two-dimensional CFT's…
We find a large class of new supersymmetric $AdS_5$ black strings from five-dimensional $N=4$ gauged supergravity coupled to five vector multiplets with $SO(2)_D\times SO(3)\times SO(3)$ gauge group. These solutions have near horizon…
We study open string amplitudes with the D3-branes in type IIB superstring theory compactified on C^2/Z_2. We introduce constant graviphoton background along the branes and calculate disk amplitudes using the NSR formalism. We take the zero…
We derive from a general formulation of pure spinor string theory on type IIA backgrounds the specific form of the action for the AdS_4 x P^3 background. We provide a complete geometrical characterization of the structure of the superfields…
Recent astrophysical data indicate that our universe might currently be in a de Sitter (dS) phase. The importance of dS space has been primarily ignited by the study of the inflationary model of the universe and the quantum gravity. As we…
Gravitational waves are investigated in Intrinsic Time Geometrodynamics. This theory has a non-vanishing physical Hamiltonian generating intrinsic time development in our expanding universe, and four-covariance is explicitly broken by…
We investigated the SU(2) Einstein-Yang-Mills system on a time-dependent non-diagonal cylindrical symmetric space-time. From the numerical investigation, wave-like solutions are found, consistent with the familiar string-like features. They…
The quantization of circular strings in an anti-de Sitter background spacetime is performed, obtaining a discrete spectrum for the string mass. A comparison with a four-dimensional homogeneous and isotropic spacetime coupled to a conformal…
We investigate the four dimensional gravitational theories which admit homogeneous but anisotropic black brane solutions in asymptotically AdS space-time. The gravitational theories we consider are 1) Einstein-Maxwell-dilaton theory, and 2)…
We construct an ambitwistor string that describes Type II supergravity on AdS$_3\times$S$^3$ with pure NS flux. The background Einstein equations ensure that the model is anomaly free. The spectrum consists of supergravity fluctuations…
We review various aspects of de Sitter spacetime in string theory: its status as an effective field theory spacetime solution, its relation to the vacuum energy problem in string theory, its (global) holographic definition in terms of two…
We compute the {\it exact} equation of state of circular strings in the (2+1) dimensional de Sitter (dS) and anti de Sitter (AdS) spacetimes, and analyze its properties for the different (oscillating, contracting and expanding) strings. The…
We observe that the pp wave limit of $AdS_5\times M^5$ compactifications of type IIB string theory is universal, and maximally supersymmetric, as long as $M^5$ is smooth and preserves some supersymmetry. We investigate a specific case,…
We consider the type IIB supergravity in ten dimensions compactified on S^1 \times T^4, with intersecting one and five D-branes in the compact dimensions. By imposing the spherical symmetry in the resulting five dimensional theory, we…
We study solutions of the supergravity equations with the string-like sources moving with the speed of light. An exact solution is obtained for the gravitational field of a boosted ring string in any dimension greater than three.
We find, from the toric description of the moduli space of D3-branes on non-compact six-dimensional singularities $\C^3/\Z_3$ and $\C^3/\Z_5$ in the blown-down limit, the four-dimensional bases on which these singular spaces are complex…
Free scalar field theory in the sector with a large number of particles can be interpreted as bosonic string theory on anti-de Sitter space of vanishing radius. Different ways of writing the field theory Hamiltonian translate to different…
We consider type IIB supergravity backgrounds corresponding to the deformed AdS_n x S^n supercoset string models of the type constructed in arXiv:1309.5850 which depend on one deformation parameter \k. In AdS_2 x S^2 case we find that the…