Gravitational baryogenesis in DGP brane cosmology

TL;DR

This paper investigates gravitational baryogenesis within DGP brane cosmology, showing that in a radiation-dominated universe, the baryon-to-entropy ratio is non-zero, differing from predictions of standard general relativity, and compares results with observational data.

Contribution

It demonstrates that gravitational baryogenesis in DGP brane cosmology yields a non-zero baryon-to-entropy ratio during radiation domination, unlike in standard general relativity.

Findings

Baryon-to-entropy ratio is non-zero in DGP cosmology for radiation domination.

The ratio aligns with observational constraints under certain conditions.

DGP brane effects modify baryogenesis predictions compared to standard GR.

Abstract

We consider the imbalance of matter and antimatter by using a gravitational baryogenesis mechanism in the background of Dvali-Gabadadze-Porrati (DGP) brane cosmology. By taking into account a flat Friedmann-Lemaitre-Robertson-Walker (FLRW) metric in the DGP brane model, we find that for a radiation dominated universe, $w = 1/3$, the ratio of baryon number density to entropy from the gravitational baryogenesis is not zero, contrary to ordinary general relativity. Also, we study the ratio of baryon number density to entropy against the observational constraints in DGP cosmology.