arXiv subjects

Santiago Perez Bergliaffa

Publications and source records attributed to Santiago Perez Bergliaffa.

3 recordsLinked to original sources

arXiv2001

Brane Worlds, String Cosmology, and AdS/CFT

Using the thin-shell formalism we discuss the motion of domain walls in de Sitter and anti-de Sitter (AdS) time-dependent bulks. This motion results in a dynamics for the brane scale factor. We show that in the case of a clean brane the scale factor describes both singular and non-singular universes, with phases of contraction and expansion. These phases can be understood as quotients of AdS spacetime by a discrete symmetry group. We discuss this effect in some detail, and suggest how the AdS/CFT correspondence could be applied to obtain a non perturbative description of brane-world string cosmology.

hep-th↗

arXiv1997

Brans-Dicke wormholes in nonvacuum spacetime

Analytical wormhole solutions in Brans-Dicke theory in the presence of matter are presented. It is shown that the wormhole throat must not be necessarily threaded with exotic matter.

gr-qc↗

arXiv1996

Variable rest masses in 5-dimensional gravitation confronted with experimental data

Cosmological solutions of Einstein equation for a \mbox{5-dimensional} space-time, in the case of a dust-filled universe, are presented. With these solutions we are able to test a hypothetical relation between the rest mass of a particle and the $5^{\rm th}$ dimension. Comparison with experiment strongly refutes the implied dependence of the rest mass on the cosmological time.

gr-qc↗