# f(R) Theories

@article{DeFelice2010fRT, title={f(R) Theories}, author={Antonio De Felice and Shinji Tsujikawa}, journal={Living Reviews in Relativity}, year={2010}, volume={13} }

Over the past decade, f(R) theories have been extensively studied as one of the simplest modifications to General Relativity. In this article we review various applications of f(R) theories to cosmology and gravity — such as inflation, dark energy, local gravity constraints, cosmological perturbations, and spherically symmetric solutions in weak and strong gravitational backgrounds. We present a number of ways to distinguish those theories from General Relativity observationally and…

## 2,622 Citations

### $f(T,R)$ theory of gravity

- Physics
- 2018

We mainly focus on the idea that the dynamics of the whole universe may be understood by making use of torsion T and curvature R at the same time. The f(T,R)-gravity can be considered as a…

### Extensions of f(R) Gravity

- Physics
- 2018

Recent cosmological observations have posed a challenge for traditional theories of gravity: what is the force driving the accelerated expansion of the universe? What if dark energy or dark matter do…

### Gravitational collapse in f(R) theories

- Physics
- 2012

We study the gravitational collapse in modified gravitational theories. In particular, we analyze a general f(R) model with uniformly collapsing cloud of self-gravitating dust particles. This…

### FRW cosmology in F(R,T) gravity

- Physics
- 2012

In this paper, we consider a theory of gravity with a metric-dependent torsion namely the F(R,T) gravity, where R is the curvature scalar and T is the torsion scalar. We study the geometric root of…

### Cosmological Perturbations in Restricted f(R)-Gravity

- Physics
- 2016

We investigate the metric perturbations of the restricted $f(R)$ theory of gravity in the cosmological context and explore the phenomenological implications of this model. We show that it is possible…

### Thermodynamics of f(R) theories of gravity

- PhysicsJournal of Cosmology and Astroparticle Physics
- 2020

This paper starts from a toy model for inflation in a class of modified theories of gravity in the metric formalism. Instead of the standard procedure—assuming a non-linear Lagrangian f(R) in the…

### Nine Years of f(R) Gravity and Cosmology

- Physics
- 2014

f(R) gravity was reintroduced in cosmology as an alternative to dark energy in explaining the current acceleration of the universe. This area of research is reviewed with emphasis on the theoretical…

### New types of f(T) gravity

- Physics
- 2011

Recently f(T) theories based on modifications of teleparallel gravity, where torsion is the geometric object describing gravity instead of curvature, have been proposed to explain the present cosmic…

### Cosmological evolution in f(R) gravity and a logarithmic model

- Physics
- 2013

In this paper, we revisit the conditions for cosmological viability of f(R) gravity and formulate them in terms of constraints on the potential of the scalaron field f'. When the scalaron is heavy,…

### A new class of Bianchi cosmological models in f(R,T) gravity

- Physics
- 2013

The new class of cosmological model of the early Universe is considered with f(R,T) modified theories of gravity (Harko et al. in Phys. Rev. D 84:024020, 2011). The exact solutions to the…

## References

SHOWING 1-10 OF 656 REFERENCES

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

- Physics
- 2007

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…

### Matter power spectrum in f(R) gravity

- Physics
- 2006

Modified gravity can be considered as an alternative to dark energy. In a generalized theory of gravity, the Universe may accelerate while containing only baryonic and dark matter. We study, in…

### Constraining Newtonian stellar configurations in f(R) theories of gravity

- Physics
- 2008

Abstract We consider general metric f ( R ) theories of gravity by solving the field equations in the presence of a spherical static mass distribution by analytical perturbative means. Expanding the…

### Large scale structure of f(R) gravity

- Physics
- 2007

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…

### f(R) Theories Of Gravity

- Physics
- 2010

Modified gravity theories have received increased attention lately due to combined motivation coming from high-energy physics, cosmology, and astrophysics. Among numerous alternatives to Einstein's…

### Disappearing cosmological constant in f(R) gravity

- Physics
- 2007

For higher-derivative f(R) gravity, where R is the Ricci scalar, a class of models is proposed, which produce viable cosmology different from the ACDM at recent times and satisfy cosmological, Solar…

### Relativistic stars in f ( R ) gravity, and absence thereof

- Physics
- 2008

Several f(R) modified gravity models have been proposed which realize the correct cosmological evolution and satisfy solar system and laboratory tests. Although nonrelativistic stellar configurations…

### f(R) gravity and chameleon theories

- Physics
- 2008

We analyze f(R) modifications of Einstein's gravity as dark energy models in the light of their connection with chameleon theories. Formulated as scalar-tensor theories, the f(R) theories imply the…

### f(R) actions, cosmic acceleration and local tests of gravity

- Physics
- 2006

We study spherically symmetric solutions in f(R) theories and its compatibility with local tests of gravity. We start by clarifying the range of validity of the weak field expansion and show that,…