Bouncing open universes embeddable in a distorted Randall-Sundrum brane scenario

In reference [1] a four-dimensional effective theory of gravity embeddable in a five-dimensional ”distorted” Randall-Sundrum brane scenario was derived. The present paper is aimed at the application of such a theory to describe physics in an open Friedmann-Robertson-Walker (Weyl-symmetric) universe. It is shown that regular bouncing universes arise for a given range of the free parameter of the theory. One of the main ingredients that enter the basis of the unification scheme of the fundamental interactions is that multiple dimensions are required. In fact, modern field theory suggests spacetime to be 4 + n-dimensional (n = 6 for string theory and n = 7 for supergravity). It is usually assumed that the additional dimensions may be compacitifed down to size of the order the Planck length or below so they are not observable. However, recent developments suggest that some of the additional dimensions may have compactification radii larger than the Planck length without conflict with observations [2]. Besides, it is possible ∗[email protected] †[email protected] ‡[email protected]