FLRW cosmology in Weyl-integrable space-time

Gannouji, Radouane; Nandan, Hemwati; Dadhich, Naresh

Keywords: Weyl-Integrable Space-Time, Cyclic Universe

Abstract

We investigate the Weyl space-time extension of general relativity (GR) for studying the FLRW cosmology through focusing and defocusing of the geodesic congruences. We have derived the equations of evolution for expansion, shear and rotation in the Weyl space-time. In particular, we consider the Starobinsky modification, f(R) = R+β*R^2-2Λ, of gravity in the Einstein-Palatini formalism, which turns out to reduce to the Weyl integrable space-time (WIST) with the Weyl vector being a gradient. The modified Raychaudhuri equation takes the form of the Hill-type equation which is then analysed to study the formation of the caustics. In this model, it is possible to have a Big Bang singularity free cyclic Universe but unfortunately the periodicity turns out to be extremely short.

Más información

Título de la Revista: JOURNAL OF COSMOLOGY AND ASTROPARTICLE PHYSICS
Volumen: 2011
Número: 11
Editorial: IOP PUBLISHING LTD
Fecha de publicación: 2011
Página de inicio: 051
Página final: 051
URL: http://stacks.iop.org/1475-7516/2011/i=11/a=051?key=crossref.cddce2ffa8b45504eafb015a58782696
DOI:

10.1088/1475-7516/2011/11/051