Kaluza-Klein Cosmology with Varying G and $\Lambda$

TL;DR

This paper explores a Kaluza-Klein cosmological model with time-varying gravitational and cosmological constants, analyzing its implications for different matter-dominated eras and comparing results with observations.

Contribution

It introduces a model with variable G and Lambda in Kaluza-Klein cosmology and examines its compatibility with observational data across different cosmological eras.

Findings

Universe not compatible with observations at epsilon=6

Compatible with observations for epsilon>6

Analyzes cosmological parameters like distance measures and statefinder

Abstract

In this paper we investigate non-compact FRW type Kaluza-Klein cosmology coupled with 5D energy-momentum tensor. The field equations are solved by taking gravitational and cosmological constants as a function of time $t$. We use $\Lambda(t)=\epsilon H^{2}$ to explore cosmological parameters including statefinder and discuss them for dust, radiation and stiff matter dominated eras. Also, we evaluate lookback time, proper distance, luminosity distance and angular diameter distance. We obtain a universe which is not compatible with current cosmological observations at $\epsilon=6$. However, for $\epsilon>6$, the results are compatible with observational cosmology.