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Title: Supergravity contributions to inflation in models with non-minimal coupling to gravity

Abstract

This paper provides a systematic study of supergravity contributions relevant for inflationary model building in Jordan frame supergravity. In this framework, canonical kinetic terms in the Jordan frame result in the separation of the Jordan frame scalar potential into a tree-level term and a supergravity contribution which is potentially dangerous for sustaining inflation. We show that if the vacuum energy necessary for driving inflation originates dominantly from the F-term of an auxiliary field (i.e. not the inflaton), the supergravity corrections to the Jordan frame scalar potential are generically suppressed. Moreover, these supergravity contributions identically vanish if the superpotential vanishes along the inflationary trajectory. On the other hand, if the F-term associated with the inflaton dominates the vacuum energy, the supergravity contributions are generically comparable to the globally supersymmetric contributions. In addition, the non-minimal coupling to gravity inherent to Jordan frame supergravity significantly impacts the inflationary model depending on the size and sign of this coupling. We discuss the phenomenology of some representative inflationary models, and point out the relation to the recently much discussed cosmological 'attractor' models.

Authors:
;  [1];  [2]
  1. Theory Division, Saha Institute of Nuclear Physics, 1/AF Saltlake, Kolkata 700064 (India)
  2. AstroParticule et Cosmologie (APC), Paris Centre for Cosmological Physics (PCCP), Université Paris Diderot, 75013 Paris (France)
Publication Date:
OSTI Identifier:
22679967
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2017; Journal Issue: 03; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ATTRACTORS; COMPARATIVE EVALUATIONS; CORRECTIONS; COUPLING; GRAVITATION; INFLATIONARY UNIVERSE; INFLATONS; SIMULATION; SUPERGRAVITY; SUPERSYMMETRY; TRAJECTORIES

Citation Formats

Das, Kumar, Dutta, Koushik, and Domcke, Valerie, E-mail: kumar.das@saha.ac.in, E-mail: valerie.domcke@apc.univ-paris7.fr, E-mail: koushik.dutta@saha.ac.in. Supergravity contributions to inflation in models with non-minimal coupling to gravity. United States: N. p., 2017. Web. doi:10.1088/1475-7516/2017/03/036.
Das, Kumar, Dutta, Koushik, & Domcke, Valerie, E-mail: kumar.das@saha.ac.in, E-mail: valerie.domcke@apc.univ-paris7.fr, E-mail: koushik.dutta@saha.ac.in. Supergravity contributions to inflation in models with non-minimal coupling to gravity. United States. doi:10.1088/1475-7516/2017/03/036.
Das, Kumar, Dutta, Koushik, and Domcke, Valerie, E-mail: kumar.das@saha.ac.in, E-mail: valerie.domcke@apc.univ-paris7.fr, E-mail: koushik.dutta@saha.ac.in. Wed . "Supergravity contributions to inflation in models with non-minimal coupling to gravity". United States. doi:10.1088/1475-7516/2017/03/036.
@article{osti_22679967,
title = {Supergravity contributions to inflation in models with non-minimal coupling to gravity},
author = {Das, Kumar and Dutta, Koushik and Domcke, Valerie, E-mail: kumar.das@saha.ac.in, E-mail: valerie.domcke@apc.univ-paris7.fr, E-mail: koushik.dutta@saha.ac.in},
abstractNote = {This paper provides a systematic study of supergravity contributions relevant for inflationary model building in Jordan frame supergravity. In this framework, canonical kinetic terms in the Jordan frame result in the separation of the Jordan frame scalar potential into a tree-level term and a supergravity contribution which is potentially dangerous for sustaining inflation. We show that if the vacuum energy necessary for driving inflation originates dominantly from the F-term of an auxiliary field (i.e. not the inflaton), the supergravity corrections to the Jordan frame scalar potential are generically suppressed. Moreover, these supergravity contributions identically vanish if the superpotential vanishes along the inflationary trajectory. On the other hand, if the F-term associated with the inflaton dominates the vacuum energy, the supergravity contributions are generically comparable to the globally supersymmetric contributions. In addition, the non-minimal coupling to gravity inherent to Jordan frame supergravity significantly impacts the inflationary model depending on the size and sign of this coupling. We discuss the phenomenology of some representative inflationary models, and point out the relation to the recently much discussed cosmological 'attractor' models.},
doi = {10.1088/1475-7516/2017/03/036},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 03,
volume = 2017,
place = {United States},
year = {Wed Mar 01 00:00:00 EST 2017},
month = {Wed Mar 01 00:00:00 EST 2017}
}
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