Bulk gravitons from a cosmological brane

TL;DR

This paper studies how gravitons emitted by a cosmological brane into a five-dimensional Anti de Sitter bulk contribute to dark radiation, using numerical methods to analyze graviton behavior and its implications for late-time cosmology.

Contribution

It provides a detailed numerical analysis of graviton emission, propagation, and bouncing in a brane-world scenario, quantifying dark radiation production in the late universe.

Findings

Graviton emission leads to measurable dark radiation.

Numerical simulations track graviton trajectories and interactions.

Results inform constraints on brane-world cosmology models.

Abstract

We investigate the emission of gravitons by a cosmological brane into an Anti de Sitter five-dimensional bulk spacetime. We focus on the distribution of gravitons in the bulk and the associated production of `dark radiation' in this process. In order to evaluate precisely the amount of dark radiation in the late low-energy regime, corresponding to standard cosmology, we study numerically the emission, propagation and bouncing off the brane of bulk gravitons.