We review recent trends in inflationary dynamics in the context of viable modified gravity
theories. After providing a general overview of the inflationary paradigm emphasizing on …

Singularities in any physical theory are either remarkable indicators of the unknown
underlying fundamental theory, or indicate a change in the description of the physical reality …

Various pulsar timing array (PTA) experiments (NANOGrav, EPTA, PPTA, CPTA, including
data from InPTA) very recently reported evidence for excess red common-spectrum signals …

Ultralight bosons can affect the dynamics of spinning black holes (BHs) via superradiant
instability, which can lead to a time evolution of the supermassive BH shadow. We study …

We provide a theoretical model of F (R) gravity in which it is possible to describe in a unified
way inflation, an early and a late dark energy era, in the presence of a light axion particle …

In the present paper, we use the holographic approach to describe the early-time
acceleration and the late-time acceleration eras of our Universe in a unified manner. Such …

Dark sector, constituting about 95% of the Universe, remains the subject of numerous
studies. There are lots of models dealing with the cause of the effects assigned to “dark …

In this work, we shall exhaustively study the effects of modified gravity on the energy
spectrum of the primordial gravitational waves background. S. Weinberg has also produced …

We consider the scenario that the effective gravitational Lagrangian of a minimally coupled
scalar field at large curvatures is described by a rescaled Einstein-Hilbert gravity, with the …

The Hubble constant tension problem is analyzed 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 …