Generalized Curvature-Matter Couplings in Modified Gravity

Galaxies

Tiberiu Harko¹ 

[1] Department of Mathematics, University College London, Gower Street, London WC1E 6BT, UK; E-Mail:

关键词: modified gravity;    curvature-matter couplings;    cosmology;    dark matter;   

DOI  :  10.3390/galaxies2030410

来源: mdpi

【 摘 要 】

In this work, we review a plethora of modified theories of gravity with generalized curvature-matter couplings. The explicit nonminimal couplings, for instance, between an arbitrary function of the scalar curvature R and the Lagrangian density of matter, induces a non-vanishing covariant derivative of the energy-momentum tensor, implying non-geodesic motion and, consequently, leads to the appearance of an extra force. Applied to the cosmological context, these curvature-matter couplings lead to interesting phenomenology, where one can obtain a unified description of the cosmological epochs. We also consider the possibility that the behavior of the galactic flat rotation curves can be explained in the framework of the curvature-matter coupling models, where the extra terms in the gravitational field equations modify the equations of motion of test particles and induce a supplementary gravitational interaction. In addition to this, these models are extremely useful for describing dark energy-dark matter interactions and for explaining the late-time cosmic acceleration.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland.