Bigravity from gradient expansion
Abstract
We discuss how the ghostfree bigravity coupled with a single scalar field can be derived from a braneworld setup. We consider DGP twobrane model without radion stabilization. The bulk configuration is solved for given boundary metrics, and it is substituted back into the action to obtain the effective fourdimensional action. In order to obtain the ghostfree bigravity, we consider the gradient expansion in which the brane separation is supposed to be sufficiently small so that two boundary metrics are almost identical. The obtained effective theory is shown to be ghost free as expected, however, the interaction between two gravitons takes the FierzPauli form at the leading order of the gradient expansion, even though we do not use the approximation of linear perturbation. We also find that the radion remains as a scalar field in the fourdimensional effective theory, but its coupling to the metrics is nontrivial.
 Authors:

 Yukawa Institute for Theoretical Physics, Kyoto University,6068502, Kyoto (Japan)
 Publication Date:
 Sponsoring Org.:
 SCOAP3, CERN, Geneva (Switzerland)
 OSTI Identifier:
 22572072
 Resource Type:
 Journal Article
 Journal Name:
 Journal of Cosmology and Astroparticle Physics
 Additional Journal Information:
 Journal Volume: 2016; Journal Issue: 05; Other Information: PUBLISHERID: JCAP05(2016)011; OAI: oai:repo.scoap3.org:15476; 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:
 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ACTION INTEGRAL; BRANES; COSMOLOGY; COUPLING; FOURDIMENSIONAL CALCULATIONS; GRAVITONS; METRICS; PARTICLE INTERACTIONS; QUANTUM FIELD THEORY
Citation Formats
Yamashita, Yasuho, Tanaka, Takahiro, and Department of Physics, Kyoto University,6068502, Kyoto. Bigravity from gradient expansion. United States: N. p., 2016.
Web. doi:10.1088/14757516/2016/05/011.
Yamashita, Yasuho, Tanaka, Takahiro, & Department of Physics, Kyoto University,6068502, Kyoto. Bigravity from gradient expansion. United States. doi:10.1088/14757516/2016/05/011.
Yamashita, Yasuho, Tanaka, Takahiro, and Department of Physics, Kyoto University,6068502, Kyoto. Wed .
"Bigravity from gradient expansion". United States. doi:10.1088/14757516/2016/05/011.
@article{osti_22572072,
title = {Bigravity from gradient expansion},
author = {Yamashita, Yasuho and Tanaka, Takahiro and Department of Physics, Kyoto University,6068502, Kyoto},
abstractNote = {We discuss how the ghostfree bigravity coupled with a single scalar field can be derived from a braneworld setup. We consider DGP twobrane model without radion stabilization. The bulk configuration is solved for given boundary metrics, and it is substituted back into the action to obtain the effective fourdimensional action. In order to obtain the ghostfree bigravity, we consider the gradient expansion in which the brane separation is supposed to be sufficiently small so that two boundary metrics are almost identical. The obtained effective theory is shown to be ghost free as expected, however, the interaction between two gravitons takes the FierzPauli form at the leading order of the gradient expansion, even though we do not use the approximation of linear perturbation. We also find that the radion remains as a scalar field in the fourdimensional effective theory, but its coupling to the metrics is nontrivial.},
doi = {10.1088/14757516/2016/05/011},
journal = {Journal of Cosmology and Astroparticle Physics},
issn = {14757516},
number = 05,
volume = 2016,
place = {United States},
year = {2016},
month = {5}
}