Two-branes with variable tension model and the effective Newtonian constant

TL;DR

This paper investigates a two-brane cosmological model with variable brane tensions following an Eotvos law, analyzing how these variations influence the effective Newtonian gravitational constant over cosmic time.

Contribution

It introduces a model where hidden brane tension varies phenomenologically, and explores its impact on the visible brane tension and the effective gravitational constant.

Findings

Visible brane tension's time derivative changes sign during evolution.

The model provides a mechanical analogy for brane tension dynamics.

Variation of the Newtonian constant is linked to brane tension behavior.

Abstract

It is shown that, in the two brane time variation model framework, if the hidden brane tension varies according to the phenomenological Eotvos law, the visible brane tension behavior is such that its time derivative is negative in the past and positive after a specific time of cosmological evolution. This behavior is interpreted in terms of an useful mechanical system analog and its relation with the variation of the Newtonian (effective) gravitational `constant' is explored.