Related papers: Superstrings on Penrose limits of AdS$_7$ solution…
We study superstring theories on the Penrose limit of the enhancon geometry realized by the D(p+4)-branes wrapped on a K3 surface. We first examine the null geodesics with fixed radius in general brane backgrounds, which give solvable…
We find a new Penrose limit of AdS_5*S^5 that gives the maximally symmetric pp-wave background of type IIB string theory in a coordinate system that has a manifest space-like isometry. This induces a new pp-wave/gauge-theory duality which…
We obtain the Penrose limit of NCYM theories in dimensions $3 \leq d \leq 6$ which originate from (D$(p-2)$, D$p$) supergravity bound state configurations for $2 \leq p \leq 5$ in the so-called NCYM limit. In most cases the Penrose limit…
The isometry algebras of the maximally supersymmetric solutions of IIB supergravity are derived by the Inonu-Wigner contractions of the super-AdS_5xS^5 algebra. The super-AdS_5xS^5 algebra allows introducing two contraction parameters; the…
The AdS/CFT correspondence provides a rich testing ground for many important topics in theoretical physics. The earliest and most striking example of the correspondence is the conjectured duality between the energy spectrum of type IIB…
We briefly review the AdS3/CFT2 correspondence and the holographic issues that arise in the Penrose limit. Exploiting current algebra techniques, developped by D'Appollonio and Kiritsis for the closely related Nappi-Witten model, we obtain…
Maximally supersymmetric spacetime algebras in eleven-dimensions, which are the isometry superalgebras of Minkowski space, AdS_7 x S^4, AdS_4 x S^7 and pp-wave background, are related by Inonu-Wigner contractions. The super-AdS_{4(7)} x…
We find a general class of pp-wave solutions of type IIB string theory such that the light cone gauge worldsheet lagrangian is that of an interacting massive field theory. When the light cone Lagrangian has (2,2) supersymmetry we can find…
We discuss the Green-Schwarz action for type IIB strings in general plane-wave backgrounds obtained as Penrose limits from any IIB supergravity solutions with vanishing background fermions. Using the normal-coordinate expansion in…
We study the Penrose limit of various AdS_p X S^q orbifolds. The limiting spaces are waves with parallel rays and singular wave fronts. In particular, we consider the orbifolds AdS_3 X S^3/\Gamma, AdS_5 X S^5/\Gamma and AdS_{4,7} X…
We consider a family of pp-wave solutions of IIB supergravity. This family has a non-trivial, constant 5-form flux, and non-trivial, (light-cone) time-dependent RR and NS-NS 3-form fluxes. The solutions have either 16 or 20 supersymmetries…
We study different Penrose limits of supergravity solution of NS5-brane in the presence of RR field. Although in the case of NS5-brane we get a 4-dimensional plane wave, in the case with RR field we will get two different plane waves; a…
The adS_{p+2} x S^{d-p-2} geometry of the near horizon branes is promoted to a supergeometry: the solution of the supergravity constraints for the vielbein, connection and form superfields are found. This supergeometry can be used for the…
We discuss light-cone gauge description of type IIB Green-Schwarz superstring in AdS_5 x S^5 with a hope to make progress towards understanding spectrum of this theory. As in flat space, fixing light cone gauge consists of two steps: (i)…
A long standing problem is the supergauge completion of AdS_4 x (G/H)_7 or AdS_5 x (G/H)_5 backgrounds which preserve less then maximal supersymmetry. In parallel with the supersolvable realization of the AdS_4 x S^7 background based on…
We consider known examples of non-supersymmetric AdS$_7$ and AdS$_4$ solutions arising from compactifications of massive type IIA supergravity and study their stability, taking into account the coupling between closed- and open-string…
In M-theory, the only AdS_7 supersymmetric solutions are AdS_7 x S^4 and its orbifolds. In this paper, we find and classify new supersymmetric solutions of the type AdS_7 x M_3 in type II supergravity. While in IIB none exist, in IIA with…
We study the hybrid formulation of Green-Schwarz superstrings on AdS_3 with NS flux and the boundary N=4 superconformal algebra. We show the equivalence between the NSR and GS superstrings by a field redefinition. The boundary N=4…
We investigate the Penrose limits of classical string and M-theory backgrounds. We prove that the number of (super)symmetries of a supergravity background never decreases in the limit. We classify all the possible Penrose limits of AdS x S…
We study type IIA string theories on the pp-waves with 24 supercharges. The type IIA pp-wave backgrounds are derived from the maximally supersymmetric pp-wave solution in eleven dimensions through the toroidal compactification on the…