Related papers: A note on obstinate tachyons in classical dS solut…
We construct supersymmetric dyon solutions based on the 't Hooft/Polyakov monopole. We show that these solutions satisfy $\kappa$ symmetry constraints and can, therefore be generalized to supersymmetric solutions of type I SO(32) string…
We analyse some physical consequences when supersymmetry is broken by a set of D-branes and/or orientifold planes in Type II string theories. Generically, there are global dilaton tadpoles at the disk level when the transverse space is…
In the Orientiworld framework the Standard Model fields are localized on D3-branes sitting on top of an orientifold 3-plane. The transverse 6-dimensional space is a non-compact orbifold (or a more general conifold). The 4-dimensional…
We discuss a novel strategy to construct 4D N=0 stable flux vacua of type II string theory, based on the existence of BPS bounds for probe D-branes in some of these backgrounds. In particular, we consider compactifications where D-branes…
We present exact solutions of four-dimensional Einstein's equations related to Minkoswki vacuum constructed from Type IIB string theory with non-trivial fluxes. Following recent works, we study a non-trivial flux compactification on a…
In this paper we analyze the structure of supersymmetric vacua in compactifications of the heterotic string on certain manifolds with SU(3) structure. We first study the effective theories obtained from compactifications on half-flat…
We show that there exist supersymmetric Minkowski vacua on Type IIB toroidal orientifold with general flux compactifications where the RR tadpole cancellation conditions can be relaxed elegantly. Then we present a realistic Pati-Salam like…
We review the six dimensional universal extra dimension models compactified on the sphere $S^2$, the orbifold $S^2/Z_2$, and the projective sphere, which are based on the spontaneous compactification mechanism on the sphere. In particular,…
We point out that the solution of $(4+n)$-dimensional gravity coupled to the dilaton and an $n$-form field strength can give rise to a flat 4-dimensional universe (with a scale factor) of the type proposed recently under time dependent…
We study consistent Kaluza-Klein reductions of type IIB supergravity on T(1,1) down to five-dimensions. We find that the most general reduction containing singlets under the global SU(2)xSU(2) symmetry of T(1,1) is N=4 gauged supergravity…
We derive the equations for the nonsupersymmetric vacua of D3-branes in the presence of nonperturbative moduli stabilization in type IIB flux compactifications, and solve and analyze them in the case of two particular 7-brane embeddings at…
I construct supersymmetric AdS$_3$ vacua of type IIB string theory that exhibit parametric scale separation in the controlled regime. These solutions arise from compactifications on seven-dimensional manifolds equipped with co-closed…
We examine the Kaluza-Klein theory for warped flux compactifications of type $II\ b $ string theory on a Minkowski spacetime $ M_4$ times a conic Calabi-Yau orientifold $X_6$. The region glued along the internal space directions to the bulk…
We search for exact tachyon kink solutions of DBI type effective action describing an unstable D-brane with worldvolume gauge field turned in both the flat and a curved background. There are various kinds of solutions in the presence of…
In this work, we present new soliton solutions for thick branes in $4+1$ dimensions. In particular, we consider brane models based on the sine-Gordon ($SG$), $\varphi^{4}$ and $\varphi^{6}$ scalar fields, which have broken $Z_{2}$ symmetry…
We consider compactifications of higher-dimensional supergravities on Riemann-flat manifolds of dimension d ($3 \le d \le 7$) that fully break supersymmetry at the classical level on a resulting D-dimensional Minkowski space. We…
New local solutions in type II supergravity that are foliations of AdS$_3\times S^3\times S^3$ over an interval and preserve at least large $\mathcal{N}=(4,0)$ supersymmetry are found. Some cases have compact internal space, some not and…
We investigate a stabilization of extra dimensions in a ten-dimensional Kaluza-Klein theory and IIB supergravity. We assume (A)dS_5 x S^5 compactifcation, and calculate quantum effects to find an effective potential for the radius of…
We investigate whether 4-dimensional static and cosmological Lifshitz solutions can be found from deforming the existing (A)dS_4 compactifications in IIA and IIA* supergravity. Using a well motivated compactification Ansatz on…
We consider the existence and stability of static configurations of a scalar field in a five dimensional spacetime in which the extra spatial dimension is compactified on an $S^1/Z_2$ orbifold. For a wide class of potentials with multiple…