Related papers: Constraining f(R) gravity with PLANCK data on gala…
The exponential $f(R)$ gravity model provides a theoretically well-motivated extension of General Relativity, introducing a modified gravitational dynamics at late times consistent with a dynamical dark energy scenario, while recovering the…
Cosmography can be considered as a sort of a model-independent approach to tackle the dark energy/modified gravity problem. In this review, the success and the shortcomings of the $\Lambda$CDM model, based on General Relativity and standard…
Using stellar dynamics and strong gravitational lensing as complementary probes, Sand et al. (2002, 2003) have recently claimed strong evidence for shallow dark matter density profiles in several lensing clusters, which may conflict with…
We study the formation of large-scale structure in universes dominated by dark matter and driven to accelerated expansion by f(R) gravity in the Palatini formalism. If the dark matter is cold, practically all of these models are ruled out…
We present an analysis of a devised sample of Rotation Curves (RCs), aimed at checking the consequences of a modified f(R) gravity on galactic scales. Originally motivated by the the dark energy mystery, this theory may serve as a…
We analyze seven different viable $f(R)$-gravities towards the Solar System tests and stochastic gravitational waves background. The aim is to achieve experimental bounds for the theory at local and cosmological scales in order to select…
Extended gravity is widely constrained in different astrophysical and astronomical systems. Since these different systems are based on different scales it is not trivial to get a combined constraint that is based on different phenomenology.…
We use a sample of 23 galaxy clusters to test the predictions of emergent gravity (EG) as alternative to dark matter. Our sample has both weak-lensing inferred total mass profiles as well as x-ray inferred baryonic gas mass profiles. Using…
Despite the success of general relativity (GR), the unexplained nature of dark energy on cosmological scales leaves open the question of whether GR provides a complete description of gravity. This quest is further motivated by growing…
Model-independent parametrisations of modified gravity have attracted a lot of attention over the past few years; numerous combinations of experiments and observables have been suggested to constrain these parameterisations, and future…
Modified theories of gravity provide us with a unique opportunity to generate innovative tests of gravity. In Chameleon f(R) gravity, the gravitational potential differs from the weak-field limit of general relativity (GR) in a mass…
Possible explanations of the observed accelerated expansion of the Universe are the introduction of a dark energy component or the modifications of gravity at large distances. A particular difference between these scenarios is the dynamics…
We investigate the modified gravity theories in terms of the effective dark energy models. We compare the cosmic expansion history and the linear growth in different models. We also study the evolution of linear cosmological perturbations…
We present the clustering of galaxy clusters as a useful addition to the common set of cosmological observables. The clustering of clusters probes the large-scale structure of the Universe, extending galaxy clustering analysis to the…
$f(R)$ theories of modified gravity may be compatible with current observations if the deviations from general relativity are sufficiently well screened in dense environments. In recent work [arXiv:2310.19955] we have shown that…
We present a Bayesian approach to combine $Planck$ data and the X-ray physical properties of the intracluster medium in the virialization region of a sample of 320 galaxy clusters ($0.056<z<1.24$, $kT>3$ keV) observed with $Chandra$. We…
The existence of the flat rotation curves of galaxies is still perplexing. The dark matter paradigm was proposed long ago to solve this conundrum; however, this proposal is still under debate. In this paper, we search for universal…
We analyse the clustering of cosmic large scale structure using a consistent modified gravity perturbation theory, accounting for anisotropic effects along and transverse to the line of sight. The growth factor has a particular scale…
We investigate f(R) theories of gravity within the Palatini approach and show how one can determine the expansion history, H(a), for an arbitrary choice of f(R). As an example, we consider cosmological constraints on such theories arising…
In this letter, we consider the theory of $F(R)$ gravity with the lagrangian density $ \pounds = R+\alpha R^2 + \beta R^2 \ln \beta R $. We obtain the constant curvature solutions and find the scalar potential of the gravitational field. We…