Marginal Deformations of N=4 SYM and Open vs. Closed String Parameters

We construct the gravity dual to the generic Leigh--Strassler deformation of N=4 SYM as well as the correponding deformed flat space geometry up to third order in the deformation parameter \rho. We achieve this by first determining the set of open string parameters (G,\Theta) encoding the deformation of the moduli space and then mapping them to the closed string ones (g,B). Our method is thus almost purely algebraic involving the supergravity equations of motion only as a consistency check. We trace the main reason for the discrepancy at higher orders in the deformation parameter to the nonassociative nature of the noncommutativity matrix \Theta