Related papers: Rindler type acceleration in f(R) gravity
In recent times, there has been an increasing interest with theories of modified gravity as a means to gain a deeper understanding of the universe's late-time acceleration phase. In this study we focused our attention on a specific…
Without abstract.
Scalar-tensor gravity is the simplest and best understood modification of general relativity, consisting of a real scalar field coupled directly to the Ricci scalar curvature. Models of this type have self-accelerating solutions. In an…
The weak field limit for a pointlike source of a $f(R) \propto R^{3/2}$-gravity model is studied. We aim to show the viability of such a model as a valid alternative to GR + dark matter at Galactic and local scales. Without considering dark…
We propose a new model of gravity where the Ricci scalar (R) in Einstein-Hilbert action is replaced by an arbitrary function of R and of the norm of energy-momentum tensor i.e., $f(R,T_{\mu\nu}T^{\mu\nu})$. Field equations are derived in…
The Hubble constant tension problem is analysed in the framework of a class of modified gravity, the so-called $F(R)$ gravity. To do so, we explore two models: an exponential and a power-law $F(R)$ gravities, which includes an early dark…
The ${\bf f}(R)$ gravity field equations are derived as an equation of state of local space-time thermodynamics. Jacobson's arguments are non-trivially extended, by means of a more general definition of local entropy, for which Wald's…
Recently a new -quantum motivated- theory of gravity has been proposed that modifies the standard Newtonian potential at large distances when spherical symmetry is considered. Accordingly, Newtonian gravity is altered by adding an extra…
In this paper, we have performed the dynamical system analysis of $f(T)$ gravity cosmological models at both background and perturbation levels. We have presented three models pertaining to three distinct functional forms of $f(T)$. The…
We obtain new exact solutions for the gravitational field equations in the context of $f(R,T)$ gravity, thereby obtaining different classes of black holes surrounded by fluids, taking into account some specific values of the parameter of…
We consider metric-affine scenarios where a modified gravitational action is sourced by electrovacuum fields in a three dimensional space-time. Such scenarios are supported by the physics of crystalline structures with microscopic defects…
Given some assumptions it is possible to derive the most general post-general relativistic theory of gravity for the distant field of a point mass. The force law derived from this theory contains a Rindler term in addition to well-known…
Positive frequency Wightman function and vacuum expectation values of the energy-momentum tensor are computed for a massive scalar field with general curvature coupling parameter and satisfying Robin boundary condition on a uniformly…
We consider a modified gravity theory, f(R)=R-a/R^n+bR^m, in the metric formulation, which has been suggested to produce late time acceleration in the Universe, whilst satisfying local fifth-force constraints. We investigate the parameter…
The issues of quintessence and cosmic acceleration can be discussed in the framework of higher order theories of gravity. We can define effective pressure and energy density directly connected to the Ricci scalar of curvature of a generic…
The metric $f(R)$ theories of gravity are generalized to five-dimensional spacetimes. By assuming a hypersurface-orthogonal Killing vector field representing the compact fifth dimension, the five-dimensional theories are reduced to their…
We propose the study of constant-roll inflation in $F(R)$ gravity. We use two different approaches, one that relates an $F(R)$ gravity to well known scalar models of constant-roll and a second that examines directly the constant-roll…
A general class of solutions of Einstein's equation for a slowly rotating fluid source, with supporting internal pressure, is matched using Lichnerowicz junction conditions, to the Kerr metric up to and including first order terms in…
In this article, we have studied a cylindrically symmetric self-gravitating dynamical object via complexity factor which is obtained through orthogonal splitting of Reimann tensor in $f(R,T)$ theory of gravity. Our study is based on the…
We consider f(R) modified gravity theories for describing varying speed of light in a spatially flat FRW model, and find some exact solutions. Also we examine the dynamics of this model by dynamical system method assuming a LambdaCDM…