Dynamics of linear perturbations in f(R) gravity
Abstract
We consider predictions for structure formation from modifications to general relativity in which the EinsteinHilbert action is replaced by a general function of the Ricci scalar. We work without fixing a gauge, as well as in explicit popular coordinate choices, appropriate for the modification of existing cosmological code. We present the framework in a comprehensive and practical form that can be directly compared to standard perturbation analyses. By considering the full evolution equations, we resolve perceived instabilities previously suggested, and instead find a suppression of perturbations. This result presents significant challenges for agreement with current cosmological structure formation observations. The findings apply to a broad range of forms of f(R) for which the modification becomes important at low curvatures, disfavoring them in comparison with the {lambda}CDM scenario. As such, these results provide a powerful method to rule out a wide class of modified gravity models aimed at providing an alternative explanation to the dark energy problem.
 Authors:
 Department of Astronomy, Cornell University, Ithaca, New York 14853 (United States)
 Department of Physics, Simon Fraser University, Burnaby, BC, V5A 1S6 (Canada)
 (United States)
 Department of Physics, Syracuse University, Syracuse, New York 13244 (United States)
 Publication Date:
 OSTI Identifier:
 21020166
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 6; Other Information: DOI: 10.1103/PhysRevD.75.064020; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ACTION INTEGRAL; COMPARATIVE EVALUATIONS; COSMOLOGY; DISTURBANCES; EINSTEIN FIELD EQUATIONS; GENERAL RELATIVITY THEORY; GRAVITATION; MODIFICATIONS; NONLUMINOUS MATTER; SCALARS
Citation Formats
Bean, Rachel, Bernat, David, Pogosian, Levon, Department of Physics, Syracuse University, Syracuse, New York 13244, Silvestri, Alessandra, and Trodden, Mark. Dynamics of linear perturbations in f(R) gravity. United States: N. p., 2007.
Web. doi:10.1103/PHYSREVD.75.064020.
Bean, Rachel, Bernat, David, Pogosian, Levon, Department of Physics, Syracuse University, Syracuse, New York 13244, Silvestri, Alessandra, & Trodden, Mark. Dynamics of linear perturbations in f(R) gravity. United States. doi:10.1103/PHYSREVD.75.064020.
Bean, Rachel, Bernat, David, Pogosian, Levon, Department of Physics, Syracuse University, Syracuse, New York 13244, Silvestri, Alessandra, and Trodden, Mark. Thu .
"Dynamics of linear perturbations in f(R) gravity". United States.
doi:10.1103/PHYSREVD.75.064020.
@article{osti_21020166,
title = {Dynamics of linear perturbations in f(R) gravity},
author = {Bean, Rachel and Bernat, David and Pogosian, Levon and Department of Physics, Syracuse University, Syracuse, New York 13244 and Silvestri, Alessandra and Trodden, Mark},
abstractNote = {We consider predictions for structure formation from modifications to general relativity in which the EinsteinHilbert action is replaced by a general function of the Ricci scalar. We work without fixing a gauge, as well as in explicit popular coordinate choices, appropriate for the modification of existing cosmological code. We present the framework in a comprehensive and practical form that can be directly compared to standard perturbation analyses. By considering the full evolution equations, we resolve perceived instabilities previously suggested, and instead find a suppression of perturbations. This result presents significant challenges for agreement with current cosmological structure formation observations. The findings apply to a broad range of forms of f(R) for which the modification becomes important at low curvatures, disfavoring them in comparison with the {lambda}CDM scenario. As such, these results provide a powerful method to rule out a wide class of modified gravity models aimed at providing an alternative explanation to the dark energy problem.},
doi = {10.1103/PHYSREVD.75.064020},
journal = {Physical Review. D, Particles Fields},
number = 6,
volume = 75,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}

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