Alok Kumar

D-brane solutions in pp-wave background

Abstract 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 × S 3 in a Penrose limit. One in addition has nontrivial RR 3-form field strength as well as a dilaton background. Classical solutions for D p -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 D p -branes in pp-wave backgrounds, obtained from string theories on AdS m × 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.

w∞ 3-algebra

We use `lone-star product of the

D-brane solutions from new isometries of pp-waves

W_{infty}

D=2,N=2, Supersymmetric theories on Non(anti)commutative Superspace

generators as well as their commutation relations to obtain a

Fermion wavefunctions in magnetized branes: Theta identities and Yukawa couplings

w_{infty}

Magnetic fluxes and moduli stabilization

3-algebra by applying appropriate double scaling limits on the generators. We show explicitly that Fundamental Identity Condition (FI) of 3-algebra is satisfied.We use `lone-star product of the W∞ generators as well as their commutation relations to obtain a w∞ 3-algebra by applying appropriate double scaling limits on the generators. We show explicitly that ``Fundamental Identity condition (FI) of 3-algebra is satisfied.

PP-waves from Nonlocal Theories

Abstract We use recently proposed translations isometries of pp-waves to construct D4- and D3-brane solutions, using T-duality transformations, in exactly solvable pp-wave background originating from AdS 3 × S 3 geometry. A unique property of the new brane solutions is the breaking of SO (10− p −1) symmetry in the transverse direction of the branes due to the presence of constant NS–NS and R–R background fluxes. We verify that our ‘localized’ solutions satisfy the field equations and explicitly present the corresponding Killing spinors. We also show the connection of our results to certain M5-branes in pp-wave geometry.

Symmetries of heterotic string theory

The classical action of a two dimensional N=2 supersymmetric theory, characterized by a general K{a}hler potential, is written down on a non(anti)commutative superspace. The action has a power series expansion in terms of the determinant of the non(anti)commutativity parameter

Ehlers transformations and string effective action

C^{alphabeta}

D-branes in PP-wave light cone string field theory

. The theory is explicitly shown to preserve half of the N=2 supersymmetry, to all orders in (det C)^n. The results are further generalized to include arbitrary superpotentials as well.