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arXiv · 1112.5823

Hubble Induced Mass in Radiation Dominated Universe

Masahiro Kawasaki·Tomohiro Takesako
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Abstract

We reconsider the effective mass of a scalar field which interact with visible sector via Planck-suppressed coupling in supergravity framework. We focus on the radiation-dominated (RD) era after inflation. In this era, the effective mass is given by thermal average of interaction terms. To make our analysis clear, we rely on Kadanoff-Baym equations to evaluate the thermal average. We find that, in RD era, a scalar field acquires the effective mass of the order of $H$.

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Masahiro Kawasaki, Tomohiro Takesako. 2012-04-06. Hubble Induced Mass in Radiation Dominated Universe. https://doi.org/10.1016/j.physletb.2012.03.069

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