riassunto2

SQG1 - Strings/Brane Motivated Gravity

Speaker

Gergely, László

Talk Title

Variable tension brane-world models

Abstract

I introduce brane-worlds with non-constant tension, strengthening the analogy with fluid membranes. This new degree of freedom allows for evolving gravitational and cosmological constants. I establish the covariant dynamics on a brane with variable tension in full generality. Then I apply the formalism for a perfect fluid on a Friedmann brane, which is embedded in a 5-dimensional charged Vaidya-Anti de Sitter space-time. The case when the Eötvös law is adopted for the temperature dependence of the brane tension is discussed in detail. The model obeys the nucleosynthesis constraints and is compatible with Ia type distant supernova data. The resulting cosmology closely mimics the standard model at late times, a decelerated phase being followed by an accelerated expansion.

Talk view

 

Back to previous page