相关论文: RG Flows Towards IR Isolated Fixed Points: Some Ty…

In the context of gauge/gravity duality, we try to understand better the proposed duality between the fractional D2-brane supergravity solutions of (Nucl. Phys. B 606 (2001) 18, hep-th/0101096) and a confining 2+1 dimensional gauge theory.…

Recently we provided a microscopic derivation of the exact supergravity profile for the twisted scalar field emitted by systems of fractional D3-branes at a Z2 orbifold singularity. In this contribution we focus on a set-up supporting an N…

In this Thesis, we focus on the study of the low energy approximation to non-critical string theories. We present an exhaustive study of their solutions, which are divided in three cases: vacuum, NSNS charged, and RR charged solutions. In…

We construct the type-IIB $AdS_4\times K$ supergravity solutions which are dual to the three-dimensional ${\cal N}=4$ superconformal field theories that arise as infrared fixed points of circular-quiver gauge theories. These superconformal…

We study metastable nonsupersymmetric configurations in type IIA string theory, obtained by suspending D4-branes and anti-D4-branes between holomorphically curved NS5's, which are related to those of hep-th/0610249 by T-duality. When the…

We review how to describe the stable non-BPS D-branes of type II string theory from a classical perspective, and discuss the properties of the space-time geometry associated to these configurations. This is relevant in order to see whether…

We find an interesting connection between perturbative large N gauge theory and closed superstrings. The gauge theory in question is found on N D3-branes placed at the tip of the cone R^6/Gamma. In our previous work we showed that, when the…

We study holographic RG flows of N=2 matter couple AdS_3 supergravities which admit both compact and non-compact sigma manifolds. For the compact case the supersymmetric domain wall solution interpolates between a conformal IR region and…

We study the $\mathcal N=2$ field theory realized by D3-branes on the ${\mathbb C}^2/{\mathbb Z}_2$ orbifold. The dual supergravity solution exhibits a repulson singularity cured by the enhancon mechanism. By comparing the open and closed…

We consider a D-brane probe in unstable string background associated with flux branes. The twist in spacetime metric reponsible for the supersymmetry breaking is shown to manifest itself in mixing of open Wilson lines with the phases of…

We consider configurations of six-branes, five-branes and eight-branes in various superstring backgrounds. These configurations give rise to $(0,1)$ supersymmetric theories in six dimensions. The condition for RR charge conservation of a…

We consider effective actions for six-dimensional non-critical superstrings. We show that the addition of $N$ units of R-R flux and of $N_f$ space-time filling D5-branes produces $AdS_5 \times S^1$ solutions with curvature comparable to the…

We propose a bottom-up approach to the building of particle physics models from string theory. Our building blocks are Type II D-branes which we combine appropriately to reproduce desirable features of a particle theory model: 1) Chirality…

Intersecting branes have been the subject of string model building for several years. This work introduces in detail the toroidal and Z_N-orientifolds, where the main discussion employs the picture of intersecting D6-branes. The derivation…

In this paper we examine a certain threebrane solution of type IIB string theory whose long-wavelength dynamics are those of a supersymmetric gauge theory in 2+1 continuous and 1 discrete dimension, all of infinite extent. Low-energy…

We consider the higher order gravity with dilaton and with the leading string theory corrections taken into account. The domain wall type solutions are investigated for arbitrary number of space-time dimensions. The explicit formulae for…

We study a bound state of fractional D3/D7-branes in the ten-dimensional space R^{1,5}*R^{4}/Z_2 using the boundary state formalism. We construct the boundary actions for this system and show that higher order terms in the twisted fields…

We discuss time-dependent backgrounds of type IIB supergravity realizing gravitation duals of gauge theories formulated in de Sitter space-time as a tool of embedding de Sitter in a supergravity. We show that only the gravitational duals to…

We construct supergravity solutions describing the near horizon limit of D1D5 systems with non-trivial boundary conditions. Upon reduction to five dimensions they define Melvin universes with NS--NS/RR fluxes, that smoothly interpolate…

We investigate the superconformal indices for the Chern-Simons-matter theories proposed for M2-branes probing the cones over N^{010}/Z_k, Q^{111}, M^{32} with N=2,3 supersymmetries and compare them with the corresponding dual gravity…