Mass eigenstates in bimetric theory with matter coupling
Abstract
In this paper we study the ghostfree bimetric action extended by a recently proposed coupling to matter through a composite metric. The equations of motion for this theory are derived using a method which avoids varying the squareroot matrix that appears in the matter coupling. We make an ansatz for which the metrics are proportional to each other and find that it can solve the equations provided that one parameter in the action is fixed. In this case, the proportional metrics as well as the effective metric that couples to matter solve Einstein's equations of general relativity including a matter source. Around these backgrounds we derive the quadratic action for perturbations and diagonalize it into generalized mass eigenstates. It turns out that matter only interacts with the massless spin2 mode whose equation of motion has exactly the form of the linearized Einstein equations, while the field with FierzPauli mass term is completely decoupled. Hence, bimetric theory, with one parameter fixed such that proportional solutions exist, is degenerate with general relativity up to linear order around these backgrounds.
 Authors:
 Department of Physics and The Oskar Klein Centre, Stockholm University, AlbaNova University Centre, Stockholm, SE106 91 Sweden (Sweden)
 Publication Date:
 OSTI Identifier:
 22382012
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2015; Journal Issue: 01; Other Information: Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; COUPLING; EIGENSTATES; EINSTEIN FIELD EQUATIONS; EQUATIONS OF MOTION; GENERAL RELATIVITY THEORY; MASS; MATHEMATICAL SOLUTIONS; MATRICES; MATTER; METRICS; PERTURBATION THEORY; SPIN
Citation Formats
SchmidtMay, Angnis, Email: angnis.schmidtmay@fysik.su.se. Mass eigenstates in bimetric theory with matter coupling. United States: N. p., 2015.
Web. doi:10.1088/14757516/2015/01/039.
SchmidtMay, Angnis, Email: angnis.schmidtmay@fysik.su.se. Mass eigenstates in bimetric theory with matter coupling. United States. doi:10.1088/14757516/2015/01/039.
SchmidtMay, Angnis, Email: angnis.schmidtmay@fysik.su.se. 2015.
"Mass eigenstates in bimetric theory with matter coupling". United States.
doi:10.1088/14757516/2015/01/039.
@article{osti_22382012,
title = {Mass eigenstates in bimetric theory with matter coupling},
author = {SchmidtMay, Angnis, Email: angnis.schmidtmay@fysik.su.se},
abstractNote = {In this paper we study the ghostfree bimetric action extended by a recently proposed coupling to matter through a composite metric. The equations of motion for this theory are derived using a method which avoids varying the squareroot matrix that appears in the matter coupling. We make an ansatz for which the metrics are proportional to each other and find that it can solve the equations provided that one parameter in the action is fixed. In this case, the proportional metrics as well as the effective metric that couples to matter solve Einstein's equations of general relativity including a matter source. Around these backgrounds we derive the quadratic action for perturbations and diagonalize it into generalized mass eigenstates. It turns out that matter only interacts with the massless spin2 mode whose equation of motion has exactly the form of the linearized Einstein equations, while the field with FierzPauli mass term is completely decoupled. Hence, bimetric theory, with one parameter fixed such that proportional solutions exist, is degenerate with general relativity up to linear order around these backgrounds.},
doi = {10.1088/14757516/2015/01/039},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 01,
volume = 2015,
place = {United States},
year = 2015,
month = 1
}

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