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arXiv · 1607.00545

Gauss-Bonnet Gravitational Baryogenesis

Abstract

In this letter we study some variant forms of gravitational baryogenesis by using higher order terms containing the partial derivative of the Gauss-Bonnet scalar coupled to the baryonic current. This scenario extends the well known theory that uses a similar coupling between the Ricci scalar and the baryonic current. One appealing feature of the scenario we study is that the predicted baryon asymmetry during a radiation domination era is non-zero. We calculate the baryon to entropy ratio for the Gauss-Bonnet term and by using the observational constraints we investigate which are the allowed forms of the $R+F(\mathcal{G})$ gravity controlling the evolution. Also we briefly discuss some alternative higher order terms that can generate a non-zero baryon asymmetry, even in the conformal invariance limit.

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BibTeXRIS

S. D. Odintsov, V. K. Oikonomou. 2016-07-02. Gauss-Bonnet Gravitational Baryogenesis. https://doi.org/10.1016/j.physletb.2016.06.074

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