Some like it hot: R 2 heals Higgs inflation, but does not cool it

Bezrukov, Fedor (The University of Manchester, School of Physics and Astronomy, Manchester, M13 9PL, United Kingdom) ; Gorbunov, Dmitry (Institute for Nuclear Research of Russian Academy of Sciences, Moscow, 117312, Russia) (Moscow Institute of Physics and Technology, Dolgoprudny, 141700, Russia) ; Shepherd, Chris (The University of Manchester, School of Physics and Astronomy, Manchester, M13 9PL, United Kingdom) ; Tokareva, Anna (Institute for Nuclear Research of Russian Academy of Sciences, Moscow, 117312, Russia)

08 July 2019

Abstract: Strong coupling in Higgs inflation at high energies hinders a joint description of inflation, reheating and low-energy dynamics. The situation may be improved with a proper UV completion of the model. A well-defined self-consistent way is to introduce an R2 -term into the action. In this modified model the strong coupling scale returns back to the Planck scale, which justifies the use of the perturbative methods in studies of the model dynamics after inflation. We investigate the reheating of the post-inflationary Universe, which involves two highly anharmonic oscillators strongly interacting with each other: homogeneous Higgs field and scalaron. We observe that in interesting regions of model parameter space these oscillations make longitudinal components of the weak gauge bosons tachyonic, triggering instant preheating at timescales much shorter than the Hubble time. The weak gauge bosons are heavy and decay promptly into light Standard Model particles, ensuring the onset of the radiation domination era right after inflation.


Published in: Physics letters B 795 (2019) 657-665 DOI: 10.1016/j.physletb.2019.06.064
License: CC-BY-3.0



Back to search

Fulltext:
Download fulltextXML Download fulltextPDF