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DOE OSTI · 3006003

Warm Inflation with the Standard Model

Berghaus, Kim V. [California Institute of Technology, Pasadena, CA (United States)] (ORCID:0000000322948188)·Drewes, Marco [Université catholique de Louvain (Belgium); Technische Universität München, Garching (Germany)] (ORCID:0000000305217586)·Zell, Sebastian [Ludwig-Maximilians-Universität, München (Germany); Max-Planck-Institut für Physik, Garching bei München (Germany); Université catholique de Louvain (Belgium)] (ORCID:0000000218743051)
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Abstract

We show for the first time that warm inflation is feasible with standard model (SM) gauge interactions alone. Our model consists of a minimal extension of the SM by a single scalar inflaton field with an axionlike coupling to gluons and a monomial potential. The effects of light fermions, which were previously argued to render warm inflation with the SM impossible, are alleviated by Hubble dilution of their chiral chemical potentials. Our model features only one adjustable combination of parameters and accommodates all inflationary observables. We briefly discuss implications for axion experiments, dark matter, and the strong 𝐶⁢𝑃 problem.

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Berghaus, Kim V. [California Institute of Technology, Pasadena, CA (United States)] (ORCID:0000000322948188), Drewes, Marco [Université catholique de Louvain (Belgium); Technische Universität München, Garching (Germany)] (ORCID:0000000305217586), Zell, Sebastian [Ludwig-Maximilians-Universität, München (Germany); Max-Planck-Institut für Physik, Garching bei München (Germany); Université catholique de Louvain (Belgium)] (ORCID:0000000218743051). 2025-10-23. Warm Inflation with the Standard Model. https://doi.org/10.1103/9nn9-bsm9

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