Localization of gravity in brane world cosmologies

TL;DR

This paper investigates how gravity can be localized on a brane within higher-dimensional spacetime, showing that zero mass gravitons can form bound states under certain conditions, affecting cosmological models.

Contribution

It demonstrates the conditions for graviton localization in brane world cosmologies, including models with positive cosmological constant, expanding understanding of gravity's behavior in higher dimensions.

Findings

Zero mass gravitons can form bound states on the brane.

Different cosmological models arise from various brane and bulk parameter choices.

Localization depends on fine-tuning of brane and bulk parameters.

Abstract

The most remarkable and interesting feature of brane world scenario is the use of bulk's curvature to localize gravity on the brane, albeit with fine tuning of the brane and bulk parameters. For FRW expanding universe on the brane, it is a moving hypersurface in Schwarzschild anti de Sitter bulk spacetime. We show that zero mass gravitons have bound state on the brane for suitable values of brane and bulk parameters. There occur various cases giving rise to different cosmological models, in particular we discuss a model with positive cosmological constant on the brane.