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arXiv · astro-ph/0611905

Gravitational Leptogenesis

Gaetano Lambiase·Subhendra Mohanty
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Abstract

We introduce a dimension five CP violating coupling between the Ricci scalar and fermions. This operator splits the energy level between neutrinos and anti-neutrinos and can generate a lepton-asymmetry in the the radiation era if heavy Majorana neutrinos decouple at the GUT scale. This operator can also generate a lepton asymmetry during warm inflation if the light neutrinos have a Majorana mass m_ν\simeq 0.25 eV which is observable in double beta decay experiments.

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Gaetano Lambiase, Subhendra Mohanty. 2006-11-29. Gravitational Leptogenesis. https://doi.org/10.1088/1475-7516%2F2007%2F12%2F008

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