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Title: Inflation from nilpotent Kähler corrections

Abstract

We develop a new class of supergravity cosmological models where inflation is induced by terms in the Kähler potential which mix a nilpotent superfield S with a chiral sector Φ. As the new terms are non-(anti)holomorphic, and hence cannot be removed by a Kähler transformation, these models are intrinsically Kähler potential driven. Such terms could arise for example due to a backreaction of an anti-D3 brane on the string theory bulk geometry. We show that this mechanism is very general and allows for a unified description of inflation and dark energy, with controllable SUSY breaking at the vacuum. When the internal geometry of the bulk field is hyperbolic, we prove that small perturbative Kähler corrections naturally lead to α-attractor behaviour, with inflationary predictions in excellent agreement with the latest Planck data.

Authors:
 [1];  [2]
  1. Ernest Rutherford Physics Building, McGill University,3600 University Street, Montréal QC, H3A 2T8 (Canada)
  2. Deutsches Elektronen-Synchrotron, DESY,Notkestraße 85, 22607 Hamburg (Germany)
Publication Date:
Sponsoring Org.:
SCOAP3, CERN, Geneva (Switzerland)
OSTI Identifier:
22572186
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2016; Journal Issue: 11; Other Information: PUBLISHER-ID: JCAP11(2016)028; OAI: oai:repo.scoap3.org:17891; cc-by 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:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ATTRACTORS; BRANES; CORRECTIONS; COSMOLOGICAL INFLATION; COSMOLOGY; INFLATIONARY UNIVERSE; NONLUMINOUS MATTER; POTENTIALS; STRING THEORY; SUPERSYMMETRY; SYMMETRY BREAKING; TRANSFORMATIONS

Citation Formats

McDonough, Evan, and Scalisi, Marco. Inflation from nilpotent Kähler corrections. United States: N. p., 2016. Web. doi:10.1088/1475-7516/2016/11/028.
McDonough, Evan, & Scalisi, Marco. Inflation from nilpotent Kähler corrections. United States. doi:10.1088/1475-7516/2016/11/028.
McDonough, Evan, and Scalisi, Marco. 2016. "Inflation from nilpotent Kähler corrections". United States. doi:10.1088/1475-7516/2016/11/028.
@article{osti_22572186,
title = {Inflation from nilpotent Kähler corrections},
author = {McDonough, Evan and Scalisi, Marco},
abstractNote = {We develop a new class of supergravity cosmological models where inflation is induced by terms in the Kähler potential which mix a nilpotent superfield S with a chiral sector Φ. As the new terms are non-(anti)holomorphic, and hence cannot be removed by a Kähler transformation, these models are intrinsically Kähler potential driven. Such terms could arise for example due to a backreaction of an anti-D3 brane on the string theory bulk geometry. We show that this mechanism is very general and allows for a unified description of inflation and dark energy, with controllable SUSY breaking at the vacuum. When the internal geometry of the bulk field is hyperbolic, we prove that small perturbative Kähler corrections naturally lead to α-attractor behaviour, with inflationary predictions in excellent agreement with the latest Planck data.},
doi = {10.1088/1475-7516/2016/11/028},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 11,
volume = 2016,
place = {United States},
year = 2016,
month =
}
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