Related papers: Comments on Noncommutative Open String Theory: V-d…
Searching for space/time noncommutativity we reconsider open strings in a constant background electric field. The main difference between this situation and its magnetic counterpart is that here there is a critical electric field beyond…
The appearance of space/time non-commutativity in theories of open strings with a constant non-diagonal background metric is considered. We show that, even if the space-time coordinates commute, when there is a metric with a time-space…
We study large N dualities for a class of ${\cal N} = 1$ theories realized on type IIB D5 branes wrapping 2-cycles of local Calabi-Yau threefolds which is obtained from resolving orbifolded conifolds or as effective field theories on D4…
We study the compactification of OM-theory on tori and show a simple heuristic derivation of the $S$-duals of noncommutative open string theory in diverse dimensions from the OM-theoretical point of view. In particular, we identify the…
U($N$) supersymmetric Yang-Mills theory naturally appears as the low-energy effective theory of a system of $N$ D-branes and open strings between them. Transverse spatial directions emerge from scalar fields, which are $N\times N$ matrices…
We consider a minimally coupled massless scalar propagating in the background of NS5-branes in the presence of a 2-form RR electric field. The supergravity solution also called the (NS5,D1) bound state in the appropriate decoupling limit is…
We show that a novel holographic correspondence appears after taking a suitable stringy non-relativistic limit of the AdS$_5$/CFT$_4$ duality. This correspondence relates string theory in String Newton-Cartan AdS$_5\times$S$^5$ with…
In string theory, D-branes can be expressed as a configuration of infinitely many lower dimensional D-branes. Using this relation, the worldvolume theory of D-branes can be regarded as the worldvolume theory of the infinitely many lower…
Recently it was shown that NCOS theories are part of a ten-dimensional theory known as Non-relativistic Wound string theory. We clarify the sense in which gravity is present in this theory. We show that Wound string theory contains…
This is a short review of the newly discovered ODp-theories that are non-gravitational six-dimensional theories defined as the decoupling limit of NS5-branes in the presence of a near-critical (p+1)-form RR fields. We discuss the motivation…
In this paper we study the noncommutativity of a moving membrane with background fields. The open string variables are analyzed. Some scaling limits are studied. The equivalence of the magnetic and electric noncommutativities is…
We investigate the holographic correspondence between (p+1)-dimensional ($0\le p\le 4$) SYM theories with 16 supercharges and superstring theories on the near-horizon limit of Dp-brane backgrounds. Following an approach based on the…
We study the commutative limit of the non-commutative maximally supersymmetric Yang-Mills theory in four dimensions (N=4 SYM). The commutative limits of non-commutative spaces are important in particular in the applications of…
We consider planar codimension-one defects and interfaces in $\mathcal{N}=4$ supersymmetric Yang-Mills (SYM) theory, realized by the D3/D5-brane intersection. Working in the probe limit, where the number of D5-branes is small compared to…
There is a subtle difference between the open string dynamics determined by the original dual resonance models and that determined by D-brane constructions within critical closed string theory. For instance, in contrast to the former, the…
This thesis follows two main lines of research, both related to relevant aspects of string theory and its phenomenological/cosmological applications. We study two different generalizations of the integrable SG model to NC geometry, after…
Various recently developed connections between supersymmetric Yang-Mills theories in four dimensions and two dimensional integrable systems serve as crucial ingredients in improving our understanding of the AdS/CFT correspondence. In this…
We study large-N double-scaling limits of U(N) gauge theories in four dimensions. We focus on theories in a partially confining phase where an abelian subgroup $\hat{G}$ of the gauge group remains unconfined. Double-scaling is defined near…
We show that a four-parameter class of 3+1 dimensional NCOS theories can be obtained by dimensional reduction on a general 2-torus from OM theory. Compactifying two spatial directions of NCOS theory on a 2-torus, we study the transformation…
We study M/D-branes in a null-brane background. By taking a near horizon limit, one is left with cosmological models in the corresponding Poincar\'e patches. To deal with their usual horizons, we either extend these models to global AdS or…