2 research outputs found
Cosmological expansion on a dilatonic brane-world
In this paper we study brane-world scenarios with a bulk scalar field, using
a covariant formalism to obtain a 4D Einstein equation via projection onto the
brane. We discuss, in detail, the effects of the bulk on the brane and how the
scalar field contribute to the gravitational effects. We also discuss choice of
conformal frame and show that the frame selected by the induced metric provides
a natural choice. We demonstrate our formalism by applying it to cosmological
scenarios of Randall-Sundrum and Horava-Witten type models. Finally we consider
the cosmology of models where the scalar field couples non-minimally to the
matter on the brane. This gives rise to a novel scenario where the universe
expands from a finite scale factor with an initial period of accelerated
expansion, thus avoiding the singularity and flatness problem of the standard
big bang model.Comment: 20 pages - Version to appear in Classical and Quantum Gravity. New
section added on conformal rescaling of the metric. Some other minor changes
made and references adde