Conflation: a new type of accelerated expansion
Abstract
In the framework of scalartensor theories of gravity, we construct a new kind of cosmological model that conflates inflation and ekpyrosis. During a phase of conflation, the universe undergoes accelerated expansion, but with crucial differences compared to ordinary inflation. In particular, the potential energy is negative, which is of interest for supergravity and string theory where both negative potentials and the required scalartensor couplings are rather natural. A distinguishing feature of the model is that, for a large parameter range, it does not significantly amplify adiabatic scalar and tensor fluctuations, and in particular does not lead to eternal inflation and the associated infinities. We also show how density fluctuations in accord with current observations may be generated by adding a second scalar field to the model. Conflation may be viewed as complementary to the recently proposed anamorphic universe of Ijjas and Steinhardt.
 Authors:

 MaxPlanckInstitute for Gravitational Physics (AlbertEinsteinInstitute),Am Mühlenberg 1, PotsdamGolm, 14476 (Germany)
 Publication Date:
 Sponsoring Org.:
 SCOAP3, CERN, Geneva (Switzerland)
 OSTI Identifier:
 22572142
 Resource Type:
 Journal Article
 Journal Name:
 Journal of Cosmology and Astroparticle Physics
 Additional Journal Information:
 Journal Volume: 2016; Journal Issue: 08; Other Information: PUBLISHERID: JCAP08(2016)073; OAI: oai:repo.scoap3.org:16998; 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); Journal ID: ISSN 14757516
 Country of Publication:
 United States
 Language:
 English
 Subject:
 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; COSMOLOGICAL INFLATION; COSMOLOGY; EXPANSION; INFLATIONARY UNIVERSE; POTENTIAL ENERGY; SCALAR FIELDS; STRING THEORY; UNIVERSE
Citation Formats
Fertig, Angelika, Lehners, JeanLuc, and Mallwitz, Enno. Conflation: a new type of accelerated expansion. United States: N. p., 2016.
Web. doi:10.1088/14757516/2016/08/073.
Fertig, Angelika, Lehners, JeanLuc, & Mallwitz, Enno. Conflation: a new type of accelerated expansion. United States. doi:10.1088/14757516/2016/08/073.
Fertig, Angelika, Lehners, JeanLuc, and Mallwitz, Enno. Wed .
"Conflation: a new type of accelerated expansion". United States. doi:10.1088/14757516/2016/08/073.
@article{osti_22572142,
title = {Conflation: a new type of accelerated expansion},
author = {Fertig, Angelika and Lehners, JeanLuc and Mallwitz, Enno},
abstractNote = {In the framework of scalartensor theories of gravity, we construct a new kind of cosmological model that conflates inflation and ekpyrosis. During a phase of conflation, the universe undergoes accelerated expansion, but with crucial differences compared to ordinary inflation. In particular, the potential energy is negative, which is of interest for supergravity and string theory where both negative potentials and the required scalartensor couplings are rather natural. A distinguishing feature of the model is that, for a large parameter range, it does not significantly amplify adiabatic scalar and tensor fluctuations, and in particular does not lead to eternal inflation and the associated infinities. We also show how density fluctuations in accord with current observations may be generated by adding a second scalar field to the model. Conflation may be viewed as complementary to the recently proposed anamorphic universe of Ijjas and Steinhardt.},
doi = {10.1088/14757516/2016/08/073},
journal = {Journal of Cosmology and Astroparticle Physics},
issn = {14757516},
number = 08,
volume = 2016,
place = {United States},
year = {2016},
month = {8}
}