We study the localization of gravity on a string-like topological defect within a 6-dimensional space-time. Assuming zero cosmological constant we find complete numerical solutions to a set of first-order, Bogomol'nyi-Prasad-Sommeferld (BPS)-like, equations for the metric and the scalar field, where the dynamics of the latter are dictated by a supergravity-type potential. Our axially symmetric ...

We consider gauged WZWmodels based on a four dimensional non-semi-simple group. We obtain conformal σ-models in D = 3 spacetime dimensions (with exact central charge c = 3) by axially and vectorially gauging a one-dimensional subgroup. The model obtained in the axial gauging is related to the 3D black string after a correlated limit is taken in the latter model. By identifying the CFT correspon...

Duality groups as (spontaneously broken) gauge symmetries for toroidal backgrounds, and their role in (∞-dimensional) underlying string gauge algebras are reviewed. For curved backgrounds, it is shown that there is a duality in the moduli space of WZNW sigma-models, that can be interpreted as a broken gauge symmetry. In particular, this duality relates the backgrounds corresponding to axially g...

We compute the amplitude for the radiation of massless NS-NS closed string states from the interaction of two moving D-branes. We consider particle-like D-branes with reference to 4-dimensional spacetime, in toroidal and orbifold compactifications, and we work out the relevant world sheet propagators within the moving boundary state formalism. We find no onshell axion emission. For large inter-...

At first, we derive a boundary state, associated with moving D$p$-brane, in the presence of Kalb-Ramond field and $U(1)$ gauge potential. Then, from interaction such D$p$-branes, obtain radiation amplitude for massless closed string. The behavior large distance branes will be studied. Our calculations is framework bosonic string theory.

Using the gauge/string duality, we model a heavy quark-antiquark pair in color singlet state moving through cold medium and explore consequences of temperature velocity on string breaking. In doing so, restrict to case two dynamical flavors. We show that breaking distance slowly varies with away from critical line but could fall near it.