Related papers: Dual Supergravity in D=10, N=1 Superspace with Tre…
Double Field Theory (DFT) is a low-energy effective theory of a manifestly $O(D,D)$ invariant formulation of the closed string theory when toroidally compactified dimensions are present. The theory is based on a doubled spacetime structure…
This contribution begins the study of the complete superfield Lagrangian description of the interacting system of D=4 N=1 supergravity (SUGRA) and supermembrane. Firstly, we review a 'three form supergravity' by Ovrut and Waldram, which we…
We solve the non-minimal case of string corrected D=10, N=1 Supergravity as the low energy limit of string theory. We find a consistent set of solutions to the Bianchi identities in the H sector, and we also find the torsions and curvatures…
We review a duality procedure that relates standard matter-coupled N=1 supergravity to dual formulations in which auxiliary fields are replaced by field-strengths of gauge three-forms. As examples, we consider the dualization of the rigid…
We derive the torsion constraints and show the consistency of equations of motion of four-dimensional Type II supergravity in superspace, with Type II sigma model. This is achieved by coupling the four-dimensional compactified Type II…
We present a new formulation for N=1, D=10 supergravity in superspace, in presence of a Lorentz Chern-Simons-form. This formulation entails the following properties: it furnishes a solution of the Bianchi identities that is algebraically…
This thesis deals with new backgrounds and concepts in Double Field Theory (DFT), a T-Duality invariant reformulation of supergravity (SUGRA). We begin by reviewing the basic concepts and notions of DFT. Afterwards, we turn to Double Field…
This text is a review of aspects of supergravity theories that are relevant in superstring cosmology. In particular, it considers the possibilities and restrictions for `uplifting terms', i.e. methods to produce de Sitter vacua. We…
We present a duality procedure that relates conventional four-dimensional matter-coupled N=1 supergravities to dual formulations in which auxiliary fields are replaced by field-strengths of gauge three-forms. The duality promotes specific…
We construct several solutions of effective actions for string theories beyond the supergravity approximation utilizing the framework of the Double Field Theory (DFT). The DFT effective actions, which are well suited for accommodating…
Type II superstring theory with mixed Dirichlet and Neumann boundary conditions admit antisymmetric tensors with varying degrees in the spectrum. We show that there exists a family of dual supergravity lagrangians to the $N=2$ type IIA…
We present a unified treatment in superspace of the two dual formulations of $D=10$, $N=1$ {\it pure} supergravity based on a strictly super-geometrical framework: the only fundamental objects are the super Riemann curvature and torsion,…
We study the holographic duals of type II and heterotic matrix string theories described by warped AdS_3 supergravities. By explicitly solving the linearized equations of motion around near horizon D-string geometries, we determine the…
We give a complete and consistent solution to string corrected (deformed), D=10, N=1 supergravity as the non-minimal low energy limit of string theory. We solve the Bianchi identities with suitable constraints to second order in the string…
We construct supergravity solutions for Dp-branes at orbifold points. The solutions are written in terms of a single function, which is the solution to a nonlinear differential equation. The near horizon limits of these solutions are dual,…
It has recently been shown that the ten-dimensional superstring can be quantized using the BRST operator $Q=\oint\lambda^\alpha d_\alpha$ where $\lambda^\alpha$ is a pure spinor satisfying $\lambda \gamma^m \lambda=0$ and $d_\alpha$ is the…
We elaborate a full superfield description of the interacting system of dynamical D=4, N=1 supergravity and dynamical superstring. As far as minimal formulation of the simple supergravity is used, such a system should contain as well the…
Motivated by Ooguri and Vafa, we study superstrings in flat R^4 in a constant self-dual graviphoton background. The supergravity equations of motion are satisfied in this background which deforms the N=2 d=4 flat space super-Poincare…
The ten-dimensional supergravity theory is a geometric low-energy effective theory and the equations of motion for its fields can be obtained from string theory by computing $\beta$ functions. With $d$ compact dimensions, we can add to it…
We study ten-dimensional N=2 maximal chiral supergravity in the context of Lie superalgebra SU(8/1). The possible successive superalgebraic truncations from ten dimensional N=2 chiral theory to the lower dimensional supergravity theories…