The Large Scale Structure of f(R) Gravity
read the original abstract
We study the evolution of linear cosmological perturbations in f(R) models of accelerated expansion in the physical frame where the gravitational dynamics are fourth order and the matter is minimally coupled. These models predict a rich and testable set of linear phenomena. For each expansion history, fixed empirically by cosmological distance measures, there exists two branches of f(R) solutions that are parameterized by B propto d^2 f/dR^2. For B<0, which include most of the models previously considered, there is a short-timescale instability at high curvature that spoils agreement with high redshift cosmological observables. For the stable B>0 branch, f(R) models can reduce the large-angle CMB anisotropy, alter the shape of the linear matter power spectrum, and qualitatively change the correlations between the CMB and galaxy surveys. All of these phenomena are accessible with current and future data and provide stringent tests of general relativity on cosmological scales.
This paper has not been read by Pith yet.
Forward citations
Cited by 5 Pith papers
-
Unveiling $f(R)$ Gravity with Void-Galaxy Cross-Correlation Multipoles
Void-galaxy cross-correlation multipoles exhibit amplified size-dependent deviations from LCDM in f(R) gravity due to the scalaron fifth force and nonlinear shell dynamics, providing a new probe for modified gravity.
-
Unveiling $f(R)$ Gravity with Void-Galaxy Cross-Correlation Multipoles
Semi-analytical calculation of void-galaxy cross-correlation multipoles in Hu-Sawicki f(R) gravity reveals size-dependent deviations from LambdaCDM up to 29.7 percent for small voids, amplified by nonlinear evolution ...
-
Positive Running of the Spectral Index for Scalar Theory and Modified Gravity
Positive running of the spectral index is achievable in Einstein-Gauss-Bonnet gravity with viable inflation, unlike standard scalar field and F(R) models which face challenges.
-
Dark Energy in Ghost-free non-local Gravity
Ghost-free non-local gravity fits Pantheon+, DESI, and H(z) data but fails with added CMB, while generalized exponential F(R) gravity outperforms Lambda CDM across all datasets including CMB.
-
Modified Gravity Theories on a Nutshell: Inflation, Bounce and Late-time Evolution
Modified gravity theories supply viable mathematical frameworks for inflation, bounces, and dark energy eras that match observational data.
discussion (0)
Sign in with ORCID, Apple, or X to comment. Anyone can read and Pith papers without signing in.