SearcharxivSearch

arXiv subjects

H. Saadat

Publications and source records attributed to H. Saadat.

4 recordsLinked to original sources

Quantum gravity effects on Hořava-Lifshitz black hole

In this paper, we would like to obtain quantum gravity effects by using Hořava-Lifshitz black hole. We consider logarithmic corrected thermodynamics quantities and investigate the effects of logarithmic correction term. Logarithmic correction comes from thermal fluctuation and may be interpreted as quantum loop corrections. As black hole is a gravitational system, hence we can investigate quantum gravity effect. We find such effects on the black hole stability and obtain domain of correction coefficient.

hep-th

A cosmological model of the early universe based on ECG with variable $Λ$-term in Lyra geometry

In this paper, we study interacting extended Chaplygin gas as dark matter and quintessence scalar field as dark energy with an effective $Λ$-term in Lyra manifold. As we know Chaplygin gas behaves as dark matter at the early universe while cosmological constant at the late time. Modified field equations are given and motivation of the phenomenological models discussed in details. Four different models based on the interaction term are investigated in this work. Then, we consider other models where Extended Chaplygin gas and quintessence field play role of dark matter and dark energy respectively with two different forms of interaction between the extended Chaplygin gas and quintessence scalar field for both constant and varying $Λ$. Concerning to the mathematical hardness of the problems we discuss results numerically and graphically. Obtained results give us hope that proposed models can work as good models for the early universe with later stage of evolution containing accelerated expansion.

gr-qc

Effect of Varying Bulk Viscosity on Generalized Chaplygin Gas

In this paper, viscous generalized Chaplygin gas as a model of dark energy considered. We assume non-constant bulk viscous coefficient and study dark energy density. We consider several cases of density-dependent viscosities. We find that, in the special case, the viscous generalized Chaplygin gas is corresponding to modified Chaplygin gas.

gr-qc