12,179 research outputs found
Wormholes in -gravity within the formalism
We propose, as a novelty in the literature, the modelling of wormholes within
the particular case of the gravity, namely , with and being the Ricci scalar and trace of the
energy-momentum tensor, respectively, while and are
constants. Although such a functional form application can be found in the
literature, those concern to compact astrophysical objects, such that no
wormhole analysis has been done so far. The quadratic geometric and linear
material corrections of this theory make the matter content of the wormhole to
remarkably be able to obey the energy conditions.Comment: Published versio
gravity models as alternatives to cosmic acceleration
This article presents cosmological models that arise in a subclass of
gravity models, with different functions and fixed
-dependence. That is, the gravitational lagrangian is considered as
, with constant . Here and represent
the Ricci scalar and trace of the stress-energy tensor, respectively. The
modified gravitational field equations are obtained through the metric
formalism for the Friedmann-Lema\^itre-Robertson-Walker metric with signature
. We work with ,
and , with and all free parameters, which lead to three different cosmological
models for our Universe. For the choice of , this reduces to widely
discussed gravity models. This manuscript clearly describes the effects
of adding the trace of the energy-momentum tensor in the lagrangian. The
exact solution of the modified field equations are obtained under the hybrid
expansion law. Also we present the Om diagnostic analysis for the discussed
models.Comment: 11 pages, 20 figures, Accepted version in EPJ
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