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We study the neutrino pairs annihilation into electron-positron pairs ($ u+{bar u}to e^- + e^+$) near the surface of a neutron star. The analysis is performed in the framework of extended theories of gravity. The latter induce a modification of the minimum photon-sphere radius ($R_{ph}$) and the maximum energy deposition rate near to $R_{ph}$, as compared to ones of General Relativity. These results might lead to an efficient mechanism for generating GRBs.
In this paper, we make a comparison for the impacts of smooth dynamical dark energy, modified gravity, and interacting dark energy on the cosmological constraints on the total mass of active neutrinos. For definiteness, we consider the $Lambda$CDM mo
We explore the impact of modified gravity on B-modes, identifying two main separate effects: lensing and propagation of tensor modes. The location of the inflationary peak of the BB spectrum depends on the speed of gravitational waves; the amplitude
The next generation of galaxy surveys will allow us to test one of the most fundamental assumptions of the standard cosmology, i.e., that gravity is governed by the general theory of relativity (GR). In this paper we investigate the ability of the Ja
Modified theories of gravity have received a renewed interest due to their ability to account for the cosmic acceleration. In order to satisfy the solar system tests of gravity, these theories need to include a screening mechanism that hides the modi
Quintessence fields, introduced to explain the speed-up of the Universe, might affect the geometry of spacetime surrounding black holes, as compared to the standard Schwarzschild and Kerr geometries. In this framework, we study the neutrino pairs ann