D-branes and BCFT in Hpp-wave backgrounds

Abstract

In this paper we study two classes of symmetric D-branes in the Nappi-Witten gravitational wave, namely D2 and S1 branes. We solve the sewing constraints and determine the bulk-boundary couplings and the boundary three-point couplings. For the D2 brane our solution gives the first explicit results for the structure constants of the twisted symmetric branes in a WZW model. We also compute the boundary four-point functions, providing examples of open string four-point amplitudes in a curved background. We finally discuss the annulus amplitudes, the relation with branes in AdS 3 and in S 3 and the analogy between the open string couplings in the H 4 model and the couplings for magnetized and intersecting branes.

Winding string condensation and noncommutative deformation of a spacelike singularity

“…Particularly they show that the two-point, three-point and four-point functions of twisted states in Misner space match the plane wave result [30]. We note that the above amplitude < φ k XX > has also been calculated in the plane wave background [31] and is non-vanishing, providing another check for the FI-type coupling used above.…”

Isometric embeddings and noncommutative branes in homogeneous gravitational waves

“…This problem is not peculiar to the class of plane wave geometries that we study, and it leads us into a detailed investigation of how D-branes behave under the Penrose-Güven limit of a spacetime. Similar analyses in some specific contexts are considered in [24,64,74]. We formulate and solve this problem in some generality, and then apply it to our specific backgrounds of interest.…”

Branes in the plane wave background with gauge field condensates

“…For other studies of D3 branes with condensates in this background by supercoset or DBI methods, see [43] and [44]. Additional comments on the related situation of branes in the Nappi-Witten background appeared recently in [45].…”