Postinflationary vacuum instability and Higgsinflaton couplings
Abstract
The Higgsinflaton coupling plays an important role in the Higgs field dynamics in the early Universe. Even a tiny coupling generated at loop level can have a dramatic effect on the fate of the electroweak vacuum. Such Higgsinflaton interaction is present both at the trilinear and quartic levels in realistic reheating models. In this work, we examine the Higgs dynamics during the preheating epoch, focusing on the effects of the parametric and tachyonic resonances. We use lattice simulations and other numerical tools in our studies. We find that the resonances can induce large fluctuations of the Higgs field which destabilize the electroweak vacuum. Our considerations thus provide an upper bound on quartic and trilinear interactions between the Higgs and the inflaton. We conclude that there exists a favorable range of the couplings within which the Higgs field is stabilized during both inflation and preheating epochs.
 Authors:
 University of Helsinki and Helsinki Institute of Physics,P.O. Box 64, Helsinki, FI00014 (Finland)
 University of Jyväskylä, Department of Physics,P.O. Box 35 (YFL), Jyväskylä, FI40014 (Finland)
 Publication Date:
 Sponsoring Org.:
 SCOAP3, CERN, Geneva (Switzerland)
 OSTI Identifier:
 22572183
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2016; Journal Issue: 11; Other Information: PUBLISHERID: JCAP11(2016)025; OAI: oai:repo.scoap3.org:17888; ccby Article funded by SCOAP3. Content from this work may be used under the terms of the Creative Commons Attribution 3.0 License. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; COMPUTERIZED SIMULATION; COSMOLOGICAL INFLATION; COUPLING; HEAT TREATMENTS; HIGGS BOSONS; HIGGS MODEL; INFLATIONARY UNIVERSE; INFLATONS; LATTICE FIELD THEORY; TACHYONS
Citation Formats
Enqvist, Kari, Karčiauskas, Mindaugas, Lebedev, Oleg, Rusak, Stanislav, and Zatta, Marco. Postinflationary vacuum instability and Higgsinflaton couplings. United States: N. p., 2016.
Web. doi:10.1088/14757516/2016/11/025.
Enqvist, Kari, Karčiauskas, Mindaugas, Lebedev, Oleg, Rusak, Stanislav, & Zatta, Marco. Postinflationary vacuum instability and Higgsinflaton couplings. United States. doi:10.1088/14757516/2016/11/025.
Enqvist, Kari, Karčiauskas, Mindaugas, Lebedev, Oleg, Rusak, Stanislav, and Zatta, Marco. Fri .
"Postinflationary vacuum instability and Higgsinflaton couplings". United States.
doi:10.1088/14757516/2016/11/025.
@article{osti_22572183,
title = {Postinflationary vacuum instability and Higgsinflaton couplings},
author = {Enqvist, Kari and Karčiauskas, Mindaugas and Lebedev, Oleg and Rusak, Stanislav and Zatta, Marco},
abstractNote = {The Higgsinflaton coupling plays an important role in the Higgs field dynamics in the early Universe. Even a tiny coupling generated at loop level can have a dramatic effect on the fate of the electroweak vacuum. Such Higgsinflaton interaction is present both at the trilinear and quartic levels in realistic reheating models. In this work, we examine the Higgs dynamics during the preheating epoch, focusing on the effects of the parametric and tachyonic resonances. We use lattice simulations and other numerical tools in our studies. We find that the resonances can induce large fluctuations of the Higgs field which destabilize the electroweak vacuum. Our considerations thus provide an upper bound on quartic and trilinear interactions between the Higgs and the inflaton. We conclude that there exists a favorable range of the couplings within which the Higgs field is stabilized during both inflation and preheating epochs.},
doi = {10.1088/14757516/2016/11/025},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 11,
volume = 2016,
place = {United States},
year = {Fri Nov 11 00:00:00 EST 2016},
month = {Fri Nov 11 00:00:00 EST 2016}
}

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