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arXiv · 1904.10510

Baryogenesis via Gravitational Spontaneous Symmetry Breaking

Abstract

We study baryogenesis in effective field theories where a $\mathrm{U}(1)_{ B-L}$-charged scalar couples to gravity via curvature invariants. We analyze the general possibilities in such models, noting the relationships between some of them and existing models, such as Affleck-Dine baryogenesis. We then identify a novel mechanism in which $\mathrm{U}(1)_{ B-L}$ can be broken by couplings to the Gauss-Bonnet invariant during inflation and reheating. Using analytic methods, we demonstrate that this mechanism provides a new way to dynamically generate the net matter-anti-matter asymmetry observed today, and verify this numerically.

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Qiuyue Liang, Jeremy Sakstein, Mark Trodden. 2019-04-23. Baryogenesis via Gravitational Spontaneous Symmetry Breaking. https://doi.org/10.1103/physrevd.100.063518

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