%0 Journal Article
%T Metric-affine f(R,T) theories of gravity and their applications
%A Barrientos, E.
%A Lobo, F. S. N.
%A Mendoza, S.
%A Olmo, G. J.
%A Rubiera-Garcia, D.
%J Physical Review D
%D 2018
%V 97
%N 10
%I Amer Physical Soc
%@ 2470-0010
%G English
%F Barrientos_etal2018
%O WOS:000433036500004
%O exported from refbase (https://references.ific.uv.es/refbase/show.php?record=3585), last updated on Wed, 06 Jun 2018 17:26:34 +0000
%X We study f (R, T) theories of gravity, where T is the trace of the energy-momentum tensor T-mu v, with independent metric and affine connection (metric-affine theories). We find that the resulting field equations share a close resemblance with their metric-affine f(R) relatives once an effective energy-momentum tensor is introduced. As a result, the metric field equations are second-order and no new propagating degrees of freedom arise as compared to GR, which contrasts with the metric formulation of these theories, where a dynamical scalar degree of freedom is present. Analogously to its metric counterpart, the field equations impose the nonconservation of the energy-momentum tensor, which implies nongeodesic motion arid consequently leads to the appearance of an extra force. The weak field limit leads to a modified Poisson equation formally identical to that found in Eddington-inspired Born-Infeld gravity. Furthermore, the coupling of these gravity theories to perfect fluids, electromagnetic, and scalar fields, and their potential applications arc discussed.
%R 10.1103/PhysRevD.97.104041
%U http://arxiv.org/abs/1803.05525
%U https://doi.org/10.1103/PhysRevD.97.104041
%P 104041-10pp