# 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…

## Figures, Tables, and Topics from this paper

## 2,231 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…

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…

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…

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…

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 constant Λ in f(R,T) modified gravity

- Physics
- 2016

In this paper, we have studied the Bianchi type-III cosmological model in the presence of cosmological constant in the context of f(R,T) modified theory of gravity. Here, we have discussed two…

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…

Study of General Relativity and $f(R)$ Modified Gravity with Cosmological Constant for Einstein and Jordan Frames

- Physics
- 2020

This thesis investigates 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…

f(R) gravity cosmology in scalar degree of freedom

- Physics
- 2014

The models of f(R) gravity belong to an important class of modified gravity models where the late time cosmic accelerated expansion is considered as the manifestation of the large scale modification…

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…

## References

SHOWING 1-10 OF 779 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…

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…

Cosmological viability of f(R)-gravity as an ideal fluid and its compatibility with a matter dominated phase

- Physics
- 2006

Constraining f ( R ) gravity as a scalar-tensor theory

- Physics
- 2007

We search for viable f(R) theories of gravity, making use of the equivalence between such theories and scalar-tensor gravity. We find that models can be made consistent with solar system constraints…

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) 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,…