Cosmological consequences of generalised RS II braneworlds

TL;DR

This paper explores how generalized RS II braneworld models with black hole bulk geometries modify cosmological equations, potentially explaining structure formation and aligning with observations.

Contribution

It introduces a generalized RS II braneworld framework with black hole bulk geometries and analyzes its implications for cosmology and structure formation.

Findings

Modified Friedmann equations with bulk black hole effects

Potential explanation for structure formation via Weyl fluid

Compatibility of model predictions with observational data

Abstract

We discuss certain features of cosmology in a generalised RS II braneworld scenario. In this scenario, the bulk is given by a Schwarzschild-anti de Sitter or a Vaidya-anti de Sitter black hole in which an FRW brane is consistently embedded, resulting in modifications of the 4-dimensional Friedmann equations. We analyse how the scenario can be visualised and discuss the significance of each term in these modified equations both for early time and for late time cosmology. We further analyse the perturbation equations, based on Newtonian as well as relativistic perturbations and show that the scenario has the potentiality to explain structure formation by the ``Weyl fluid'' arising from embedding geometry. The results thus obtained are confronted with observations as well.