Is a Higgs vacuum instability fatal for highscale inflation?
Abstract
We study the inflationary evolution of a scalar field h with an unstable potential for the case where the Hubble parameter H during inflation is larger than the instability scale Λ _{I} of the potential. Quantum fluctuations in the field of size δh ~ H/2π imply that the unstable part of the potential is sampled during inflation. We investigate the evolution of these fluctuations to the unstable regime and in particular whether they generate cosmological defects or even terminate inflation. We apply the results of a toy scalar model to the case of the Standard Model (SM) Higgs boson, the quartic of which evolves to negative values at high scales, and extend previous analyses of Higgs dynamics during inflation utilizing statistical methods to a perturbative and fully gaugeinvariant formulation. We show that the dynamics are controlled by the renormalization groupimproved quartic coupling λ(μ) evaluated at a scale μ = H, such that Higgs fluctuations are enhanced by the instability if H > Λ _{I}. Even if H > Λ _{I}, the instability in the Standard Model Higgs potential does not end inflation; instead the universe slowly sloughs off crunching patches of space that never come to dominate the evolution. Asmore »
 Authors:
 Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
 Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Univ. of California, Berkeley, CA (United States)
 Publication Date:
 Research Org.:
 Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)
 Sponsoring Org.:
 USDOE Office of Science (SC), High Energy Physics (HEP) (SC25)
 OSTI Identifier:
 1226319
 Alternate Identifier(s):
 OSTI ID: 1198521
 Report Number(s):
 FERMILABPUB15090T
Journal ID: ISSN 15507998; PRVDAQ; arXiv eprint number arXiv:1503.05193
 Grant/Contract Number:
 AC0207CH11359; AC0205CH11231; SC0007859
 Resource Type:
 Journal Article: Accepted Manuscript
 Journal Name:
 Physical Review. D, Particles, Fields, Gravitation and Cosmology
 Additional Journal Information:
 Journal Volume: 91; Journal Issue: 12; Journal ID: ISSN 15507998
 Publisher:
 American Physical Society (APS)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 79 ASTRONOMY AND ASTROPHYSICS; 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
Citation Formats
Kearney, John, Yoo, Hojin, and Zurek, Kathryn M. Is a Higgs vacuum instability fatal for highscale inflation?. United States: N. p., 2015.
Web. doi:10.1103/PhysRevD.91.123537.
Kearney, John, Yoo, Hojin, & Zurek, Kathryn M. Is a Higgs vacuum instability fatal for highscale inflation?. United States. doi:10.1103/PhysRevD.91.123537.
Kearney, John, Yoo, Hojin, and Zurek, Kathryn M. Thu .
"Is a Higgs vacuum instability fatal for highscale inflation?". United States.
doi:10.1103/PhysRevD.91.123537. https://www.osti.gov/servlets/purl/1226319.
@article{osti_1226319,
title = {Is a Higgs vacuum instability fatal for highscale inflation?},
author = {Kearney, John and Yoo, Hojin and Zurek, Kathryn M.},
abstractNote = {We study the inflationary evolution of a scalar field h with an unstable potential for the case where the Hubble parameter H during inflation is larger than the instability scale ΛI of the potential. Quantum fluctuations in the field of size δh ~ H/2π imply that the unstable part of the potential is sampled during inflation. We investigate the evolution of these fluctuations to the unstable regime and in particular whether they generate cosmological defects or even terminate inflation. We apply the results of a toy scalar model to the case of the Standard Model (SM) Higgs boson, the quartic of which evolves to negative values at high scales, and extend previous analyses of Higgs dynamics during inflation utilizing statistical methods to a perturbative and fully gaugeinvariant formulation. We show that the dynamics are controlled by the renormalization groupimproved quartic coupling λ(μ) evaluated at a scale μ = H, such that Higgs fluctuations are enhanced by the instability if H > ΛI. Even if H > ΛI, the instability in the Standard Model Higgs potential does not end inflation; instead the universe slowly sloughs off crunching patches of space that never come to dominate the evolution. As inflation proceeds past 50 efolds, a significant proportion of patches exits inflation in the unstable vacuum, and as much as 1% of the spacetime can rapidly evolve to a defect. Depending on the nature of these defects, however, the resulting universe could still be compatible with ours.},
doi = {10.1103/PhysRevD.91.123537},
journal = {Physical Review. D, Particles, Fields, Gravitation and Cosmology},
number = 12,
volume = 91,
place = {United States},
year = {Thu Jun 25 00:00:00 EDT 2015},
month = {Thu Jun 25 00:00:00 EDT 2015}
}
Web of Science

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