arXiv subjects
Publications and source records attributed to Sanjay.
We derive intersecting brane solutions in pp-wave spacetime by solving the supergravity field equations explicitly. The general intersection rules are presented. We also generalize the construction to the non-extremal solutions. Both the extremal and non-extremal solutions presented here are asymptotic to BFHP plane waves. We find that these solutions do not have regular horizons.
We find classical solutions of D-branes in pp-wave spacetime with nonconstant NS-NS flux. We also present Dp-Dp' bound state solutions in this background. We further analyze the supersymmetric properties of these brane solutions by solving the type IIB killing spinor equations explicitly.
We discuss the role of singletons and logarithmic operators in AdS_3 string theory in the context of AdS_3/CFT_2 correspondence.
We present classical solutions for a D5 and NS5-branes in a pp-wave background. The worldvolume coordinates for these branes lie along a six dimensional pp-wave configuration obtained from $AdS_3 \times S_3$ in a Penrose limit. One in addition has nontrivial R-R 3-form field strength as well as a dilaton background. Classical solutions for Dp-branes (p> 5), as well as their bound states, are then generated in both IIA and IIB string theories by using T-duality symmetries. We also briefly discuss the construction of Dp-branes in pp-wave backgrounds, obtained from string theories on $AdS_m\times S^m$. Finally, the construction of the above D5-brane solution is presented from the point of view of the Green-Schwarz worldsheet string theory and its low lying spectrum is discussed.
We find some exact solutions of the Knizhnik-Zamolodchikov equation for the four point correlation functions that occur in the SL(2,R) WZNW model. They exhibit logarithmic behaviour in both the Kac-Moody and Virasoro parts. We discuss their implication for the operator product expansion. We also observe the appearance of several symmetries of the correlation functions.
We analyse the leading logarithmic singularities in direct and crossed channel limit of the four-point functions in dilaton-axion sector of type IIB supergravity on $AdS_{5}$ in AdS/CFT correspondence. Logarithms do not cancel in the full correlator in both channels.