EFFECTIVE EQUATIONS ON THE 3-BRANE WORLD FROM TYPE IIB STRING

Abstract

The effective field equations on a 3-brane are established considering the massless bosonic sector of the type IIB string compactified on S5. The covariant embedding formalism in a space endowed with Z2-symmetry is applied. Recently the derivation of the effective equations on the 3-brane, where only gravity penetrates in the bulk was performed by Shiromizu, Maeda, and Sasaki. We extend this approach to the situation when the bulk contains a set of fields given by the type IIB string. The notion of the Einstein–Cartan space is considered in order to avoid extra suppositions about the embedding of these fields. The interactions between the brane and the bulk fields are understood in a purely geometric way, which fixes the form of these interactions. Finally, we present the dynamically equivalent effective equations expressed completely in Riemannian terms and make conclusions.