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Title: Violent preheating in inflation with nonminimal coupling

Abstract

We study particle production at the preheating era in inflation models with nonminimal coupling ξφ{sup 2} R and quartic potential λφ{sup 4}/4 for several cases: real scalar inflaton, complex scalar inflaton and Abelian Higgs inflaton. We point out that the preheating proceeds much more violently than previously thought. If the inflaton is a complex scalar, the phase degree of freedom is violently produced at the first stage of preheating. If the inflaton is a Higgs field, the longitudinal gauge boson production is similarly violent. This is caused by a spike-like feature in the time dependence of the inflaton field, which may be understood as a consequence of the short time scale during which the effective potential or kinetic term changes suddenly. The produced particles typically have very high momenta k ∼< √λ M {sub P}. The production might be so strong that almost all the energy of the inflaton is carried away within one oscillation for ξ{sup 2}λ ∼> O(100). This may partly change the conventional understandings of the (p)reheating after inflation with the nonminimal coupling to gravity such as Higgs inflation. We also discuss the possibility of unitarity violation at the preheating stage.

Authors:
;  [1];  [2];  [3]
  1. Department of Physics, Faculty of Science, The University of Tokyo, Bunkyo-ku, Tokyo 133-0033 (Japan)
  2. Center for Theoretical Physics of the Universe, Institute for Basic Science (IBS), Daejeon 34051 (Korea, Republic of)
  3. Kavli IPMU (WPI), UTIAS, The University of Tokyo, Kashiwa, Chiba 277-8583 (Japan)
Publication Date:
OSTI Identifier:
22680011
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2017; Journal Issue: 02; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; COMPUTERIZED SIMULATION; COUPLING; HIGGS MODEL; INFLATIONARY UNIVERSE; INFLATONS; PARTICLE PRODUCTION; QUANTUM GRAVITY

Citation Formats

Ema, Yohei, Nakayama, Kazunori, Jinno, Ryusuke, and Mukaida, Kyohei, E-mail: ema@hep-th.phys.s.u-tokyo.ac.jp, E-mail: jinno@ibs.re.kr, E-mail: kyohei.mukaida@ipmu.jp, E-mail: kazunori@hep-th.phys.s.u-tokyo.ac.jp. Violent preheating in inflation with nonminimal coupling. United States: N. p., 2017. Web. doi:10.1088/1475-7516/2017/02/045.
Ema, Yohei, Nakayama, Kazunori, Jinno, Ryusuke, & Mukaida, Kyohei, E-mail: ema@hep-th.phys.s.u-tokyo.ac.jp, E-mail: jinno@ibs.re.kr, E-mail: kyohei.mukaida@ipmu.jp, E-mail: kazunori@hep-th.phys.s.u-tokyo.ac.jp. Violent preheating in inflation with nonminimal coupling. United States. doi:10.1088/1475-7516/2017/02/045.
Ema, Yohei, Nakayama, Kazunori, Jinno, Ryusuke, and Mukaida, Kyohei, E-mail: ema@hep-th.phys.s.u-tokyo.ac.jp, E-mail: jinno@ibs.re.kr, E-mail: kyohei.mukaida@ipmu.jp, E-mail: kazunori@hep-th.phys.s.u-tokyo.ac.jp. Wed . "Violent preheating in inflation with nonminimal coupling". United States. doi:10.1088/1475-7516/2017/02/045.
@article{osti_22680011,
title = {Violent preheating in inflation with nonminimal coupling},
author = {Ema, Yohei and Nakayama, Kazunori and Jinno, Ryusuke and Mukaida, Kyohei, E-mail: ema@hep-th.phys.s.u-tokyo.ac.jp, E-mail: jinno@ibs.re.kr, E-mail: kyohei.mukaida@ipmu.jp, E-mail: kazunori@hep-th.phys.s.u-tokyo.ac.jp},
abstractNote = {We study particle production at the preheating era in inflation models with nonminimal coupling ξφ{sup 2} R and quartic potential λφ{sup 4}/4 for several cases: real scalar inflaton, complex scalar inflaton and Abelian Higgs inflaton. We point out that the preheating proceeds much more violently than previously thought. If the inflaton is a complex scalar, the phase degree of freedom is violently produced at the first stage of preheating. If the inflaton is a Higgs field, the longitudinal gauge boson production is similarly violent. This is caused by a spike-like feature in the time dependence of the inflaton field, which may be understood as a consequence of the short time scale during which the effective potential or kinetic term changes suddenly. The produced particles typically have very high momenta k ∼< √λ M {sub P}. The production might be so strong that almost all the energy of the inflaton is carried away within one oscillation for ξ{sup 2}λ ∼> O(100). This may partly change the conventional understandings of the (p)reheating after inflation with the nonminimal coupling to gravity such as Higgs inflation. We also discuss the possibility of unitarity violation at the preheating stage.},
doi = {10.1088/1475-7516/2017/02/045},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 02,
volume = 2017,
place = {United States},
year = {Wed Feb 01 00:00:00 EST 2017},
month = {Wed Feb 01 00:00:00 EST 2017}
}
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