# Matter may matter

@article{Haghani2014MatterMM,
title={Matter may matter},
author={Zahra Haghani and Tiberiu Harko and Hamid Reza Sepangi and Shahab Shahidi},
journal={International Journal of Modern Physics D},
year={2014},
volume={23},
pages={1442016}
}
• Z. Haghani, +1 author S. Shahidi
• Published 15 May 2014
• Physics
• International Journal of Modern Physics D
We propose a gravitational theory in which the effective Lagrangian of the gravitational field is given by an arbitrary function of the Ricci scalar, the trace of the matter energy–momentum tensor, and the contraction of the Ricci tensor with the matter energy–momentum tensor. The matter energy–momentum tensor is generally not conserved, thus leading to the appearance of an extra-force, acting on massive particles in a gravitational field. The stability conditions of the theory with respect to… Expand
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#### References

SHOWING 1-10 OF 37 REFERENCES
f(R,Lm) gravity
• Physics
• 2010
We generalize the f(R) type gravity models by assuming that the gravitational Lagrangian is given by an arbitrary function of the Ricci scalar R and of the matter Lagrangian Lm. We obtain theExpand
Further matters in space-time geometry: f(R,T,RμνTμν) gravity
• Physics
• 2013
for the extra-acceleration which depends on the matter density is obtained in the small velocity limit for dust particles. We also analyze in detail the so-called Dolgov-Kawasaki instability, andExpand
Modified gravity with arbitrary coupling between matter and geometry
The field equations of a generalized f(R) type gravity model, in which there is an arbitrary coupling between matter and geometry, are obtained. The equations of motion for test particles are derivedExpand
Dark matter as a geometric effect in f(R) gravity
• Physics
• 2008
Abstract We consider the behavior of the tangential velocity of test particles moving in stable circular orbits in f ( R ) modified theories of gravity. A large number of observations at the galacticExpand
Extra force in f(R) modified theories of gravity
• Physics
• 2007
The equation of motion for massive particles in f(R) modified theories of gravity is derived. By considering an explicit coupling between an arbitrary function of the scalar curvature, R, and theExpand
$f(R,T)$ gravity
• Physics
• 2011
We consider $f(R,T)$ modified theories of gravity, where the gravitational Lagrangian is given by an arbitrary function of the Ricci scalar $R$ and of the trace of the stress-energy tensor $T$. WeExpand
f(R) Theories
• Physics, Medicine
• Living reviews in relativity
• 2010
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 are reviewed. Expand
Unified cosmic history in modified gravity: From F ( R ) theory to Lorentz non-invariant models
• Physics
• 2010
Classical generalization of general relativity is considered as gravitational alternative for unified description of the early-time inflation with late-time cosmic acceleration. The structure andExpand
Brane-World Gravity
• Physics, Medicine
• Living reviews in relativity
• 2010
This review analyzes the geometry, dynamics and perturbations of simple brane-world models for cosmology and astrophysics, mainly focusing on warped 5-dimensional brane -worlds based on the Randall-Sundrum models. Expand
The Dark side of gravity: Modified theories of gravity
Modern astrophysical and cosmological models are faced with two severe theoretical difficulties, that can be summarized as the dark energy and the dark matter problems. Relative to the former, it hasExpand