Brax, P., van de Bruck, C. and Davis, A.-C. (2020) Swampland and screened modified gravity. Physical Review D, 101 (8). 083514. ISSN 2470-0010
Abstract
We consider the implications of the swampland conjectures on scalar-tensor theories defined in the Einstein frame in which the scalar interaction is screened. We show that chameleon models are not in the swampland provided the coupling to matter is larger than unity and the mass of the scalar field is much larger than the Hubble rate. We apply these conditions to the inverse power law chameleon and the symmetron. We then focus on the dilaton of string theory in the strong coupling limit, as defined in the string frame. We show that solar system tests of gravity imply that viable dilaton models are not in the swampland. In the future of the Universe, if the low-energy description with a single scalar is still valid and the coupling to matter remains finite, we find that the scalar field energy density must vanish for models with the chameleon and symmetron mechanisms. Hence in these models dark energy is only a transient phenomenon. This is not the case for the strongly coupled dilaton, which keeps evolving slowly, leading to a quasi–de Sitter spacetime.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2020 Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. (https://creativecommons.org/licenses/by/4.0/) Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP3. |
Keywords: | hep-th; hep-th; astro-ph.CO; gr-qc; hep-ph |
Dates: |
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Institution: | The University of Sheffield |
Academic Units: | The University of Sheffield > Faculty of Science (Sheffield) > School of Mathematics and Statistics (Sheffield) |
Funding Information: | Funder Grant number Science and Technology Facilities Council (STFC) ST/P000800/1 |
Depositing User: | Symplectic Sheffield |
Date Deposited: | 03 Dec 2019 12:08 |
Last Modified: | 27 May 2020 10:22 |
Status: | Published |
Publisher: | American Physical Society |
Refereed: | Yes |
Identification Number: | 10.1103/PhysRevD.101.083514 |
Related URLs: | |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:154142 |