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arXiv · hep-ph/0402174

The masses of weakly-coupled scalar fields in the early Universe

David H. Lyth·Takeo Moroi
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Abstract

We consider the effective mass-squared in the early Universe, of a scalar field which has only Planck-suppressed couplings with light fields and whose true mass is less than the Hubble parameter $H$. A detailed investigation shows that the effective mass-squared generically is of order $\pm H^2$ during inflation and matter-domination, but much smaller during radiation domination. We consider the special circumstances under which the mass-squared may be much bigger or much smaller than the generic value.

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David H. Lyth, Takeo Moroi. 2004-05-10. The masses of weakly-coupled scalar fields in the early Universe. https://doi.org/10.1088/1126-6708%2F2004%2F05%2F004

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