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arXiv · 1610.01453

Gravitational Baryogenesis in Running Vacuum models

V. K. Oikonomou·Supriya Pan·Rafael C. Nunes
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Abstract

We study the gravitational baryogenesis mechanism for generating baryon asymmetry in the context of running vacuum models. Regardless if these models can produce a viable cosmological evolution, we demonstrate that they produce a non-zero baryon-to-entropy ratio even if the universe is filled with conformal matter. This is a sound difference between the running vacuum gravitational baryogenesis and the Einstein-Hilbert one, since in the latter case, the predicted baryon-to-entropy ratio is zero. We consider two well known and most used running vacuum models and show that the resulting baryon-to-entropy ratio is compatible with the observational data. Moreover, we also show that the mechanism of gravitational baryogenesis may constrain the running vacuum models.

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V. K. Oikonomou, Supriya Pan, Rafael C. Nunes. 2016-10-05. Gravitational Baryogenesis in Running Vacuum models. https://doi.org/10.1142/s0217751x17501299

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