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Title: Limit to general relativity in f(R) theories of gravity

Abstract

We discuss two aspects of f(R) theories of gravity in metric formalism. We first study the reasons to introduce a scalar-tensor representation for these theories and the behavior of this representation in the limit to General Relativity, f(R){yields}R. We find that the scalar-tensor representation is well behaved even in this limit. Then we work out the exact equations for spherically symmetric sources using the original f(R) representation, solve the linearized equations, and compare our results with recent calculations of the literature. We observe that the linearized solutions are strongly affected by the cosmic evolution, which makes very unlikely that the cosmic speedup be due to f(R) models with correcting terms relevant at low curvatures.

Authors:
 [1]
  1. Physics Department, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin 53201 (United States)
Publication Date:
OSTI Identifier:
20935211
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 75; Journal Issue: 2; Other Information: DOI: 10.1103/PhysRevD.75.023511; (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; COSMOLOGICAL MODELS; COSMOLOGY; EQUATIONS; GALACTIC EVOLUTION; GENERAL RELATIVITY THEORY; GRAVITATION; MATHEMATICAL SOLUTIONS; SCALARS; TENSORS

Citation Formats

Olmo, Gonzalo J. Limit to general relativity in f(R) theories of gravity. United States: N. p., 2007. Web. doi:10.1103/PHYSREVD.75.023511.
Olmo, Gonzalo J. Limit to general relativity in f(R) theories of gravity. United States. doi:10.1103/PHYSREVD.75.023511.
Olmo, Gonzalo J. Mon . "Limit to general relativity in f(R) theories of gravity". United States. doi:10.1103/PHYSREVD.75.023511.
@article{osti_20935211,
title = {Limit to general relativity in f(R) theories of gravity},
author = {Olmo, Gonzalo J.},
abstractNote = {We discuss two aspects of f(R) theories of gravity in metric formalism. We first study the reasons to introduce a scalar-tensor representation for these theories and the behavior of this representation in the limit to General Relativity, f(R){yields}R. We find that the scalar-tensor representation is well behaved even in this limit. Then we work out the exact equations for spherically symmetric sources using the original f(R) representation, solve the linearized equations, and compare our results with recent calculations of the literature. We observe that the linearized solutions are strongly affected by the cosmic evolution, which makes very unlikely that the cosmic speedup be due to f(R) models with correcting terms relevant at low curvatures.},
doi = {10.1103/PHYSREVD.75.023511},
journal = {Physical Review. D, Particles Fields},
number = 2,
volume = 75,
place = {United States},
year = {Mon Jan 15 00:00:00 EST 2007},
month = {Mon Jan 15 00:00:00 EST 2007}
}
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