Related papers: Smeared versus localised sources in flux compactif…
We review recent attempts to try to combine global issues of string compactifications, like moduli stabilisation, with local issues, like semi-realistic D-brane constructions. We list the main problems encountered, and outline a possible…
In the Matrix theories compactified on the $d$ dimensional torus with $d = 5, 6, 7$ which are described by the theories of D$d$-branes in the type IIA or IIB theory on the $d$ dimensional dual torus we analyze the BPS bound states of the…
We prove the existence of a new class of BPS saturated M-branes. They are in one-to-one correspondence with the Freund--Rubin compactifications of M-theory on either (AdS_4) x (G/H) or (AdS_7) x (G/H), where G/H is the seven (or four)…
Nongeometric flux compactifications with frozen complex structure moduli have been recently studied for several phenomenological purposes. In this context, we analyze the possibility of realizing de-Sitter solutions in the context of ${\cal…
Summarizing the results of arXiv:0707.1038, we discuss the four-dimensional effective approach to type II N=1 supersymmetric flux compactifications with general SU(3)x SU(3)-structure. In particular, we study the effect of a non-trivial…
We study AdS$_3\times \text{S}^2$ solutions in massive IIA that preserve small ${\cal N}=(4,0)$ supersymmetry in terms of an SU(2)-structure on the remaining internal space. We find two new classes of solutions that are warped products of…
We describe how local toric singularities, including the Toric Lego construction, can be embedded in compact Calabi-Yau manifolds. We study in detail the addition of D-branes, including non-compact flavor branes as typically used in…
On the Type IIB toroidal T^6 orientifolds with generic flux compactifications, we conjecture that in generic supsersymmetric Minkowski vacua, at least one of the flux contributions to the seven-brane and D3-brane tadpoles is positive if the…
We improve on the understanding of the backreaction of anti-D6-branes in a flux background that is mutually BPS with D6-branes. This setup is analogous to the study of the backreaction of anti-D3-branes inserted in the KS throat, but does…
We investigate supersymmetric flows in type IIB supergravity that preserve an $SO(2,2)$ space-time symmetry and asymptote to $AdS_{5} \times S^5$ at both endpoints. The flows are constructed as Janus-type $\mathbb{R} \times AdS_{3}$ BPS…
We establish the relation between the structure governing supersymmetric and non-supersymmetric four- and five-dimensional black holes and multicenter solutions and Calabi-Yau flux compactifications of M-theory and type IIB string theory.…
Flux compactifications of IIA supergravity on orientifolded G$_2$-manifolds have been argued to allow for classical Minkowski$_3$ vacua with moduli and scale-separated AdS$_3$ vacua with full moduli stabilisation. To further uplift these…
In this work we study type IIB Calabi-Yau orientifold compactifications in the presence of space-time filling D7-branes and O7-planes. In particular, we conclude that $\alpha'^2 g_s$-corrections to their DBI actions lead to a modification…
We show that the $D=11$ Supermembrane theory (M2-brane) compactified on a $M_9 \times T^2$ target space, with constant fluxes $C_{\pm}$ naturally incorporates the geometrical structure of a twisted torus. We extend the M2-brane theory to a…
We present special classes of orientifold models involving supersymmetry breaking via branes at angles. Type II superstring theories are compactified on a two torus times a four-dimensional orbifold. Combining worldsheet parity with a…
We present orientifold models of type IIA string theory with D8-branes compactified on a two torus times a four dimensional orbifold. The orientifold group is chosen such that one coordinate of the two torus is reversed when applying…
We show the existence of classical solutions of a system of D3-branes oriented at an arbitrary angle with respect to each other, in a six dimensional pp-wave background obtained from AdS_3\times S^3\times R^4, with NS-NS and R-R 3-form…
We solve for the complete space of linearized deformations of the Klebanov-Strassler background consistent with the symmetries preserved by a stack of anti-D3 branes smeared on the $S^3$ of the deformed conifold. We find that the only…
D7-brane moduli are stabilized by worldvolume fluxes, which contribute to the D3-brane tadpole. We calculate this contribution in the Type IIB limit of F-theory compactifications on Calabi-Yau four-folds with a weak Fano base, and are able…
Stabilization of closed string moduli in toroidal orientifold compactifications of type IIB string theory are studied using constant internal magnetic fields on D-branes and 3-form fluxes that preserve N=1 supersymmetry in four dimensions.…