KALUZA - KLEIN COSMOLOGICAL MODEL WITH QUARK AND STRANGE QUARK MATTER INF(R,T)GRAVITY

In this paper,Kaluza-Klein space-time with quark and strange quark matter in gravity has been considered. The general solutions of the field equations of Kaluza-Klein space-time have been obtained under the assumption of constant deceleration parameter. The physical and geometrical aspects of the model are also discussed in details.

Study of cosmic models in f(R,T) gravity with tilted observers

In this work, we have studied LRS Bianchi type I cosmological models in [Formula: see text] gravity with tilted observers, where [Formula: see text] is the Ricci scalar and [Formula: see text] is the trace of the stress energy tensor. We have explored a tilted model and determined the solutions of the field equations by assuming special law of variation of Hubble’s parameter, proposed by Berman (1983) that yields constant deceleration parameter. In this scenario, we have used the equation of state [Formula: see text] and power law of velocity to describe the different anisotropic physical models such as Dust Universe, Radiation Universe, Hard Universe and Zedovich Universe. We have discussed graphical presentation of all parameters of the derived models with the help of MATLAB. Some physical and geometrical aspects of the models are also discussed.

Cosmological viscous fluid models describing infinite time singularities in f(T) gravity

In this paper we explore the state parameter behaviour of the interacting viscous dark energy in f(T) gravity. Using constant deceleration parameter we investigate the cosmological implications of the viscosity and interaction between the dark components (energy and matter) in terms of Redshift. So doing, the viscosity and the interaction between the two fluids are parameterized by constants $$\delta $$ δ and $$\xi $$ ξ respectively. In the later part of the paper, we explore some bulk viscosity models describing Little Rip and Pseudo Rip future singularities within f(T) modified gravity. We obtain gravitational equations of motion for viscous dark energy coupled with dark matter. Solving these equations, we found analytic expressions for characteristic properties of these cosmological models.

Relationship between magnetic field and anisotropy parameter in gravitation theories

The magnetized strange quark matter (MSQM) solutions are obtained for a Marder type universe using constant deceleration parameter. The exact solutions of field equations are obtained for f(R,[Formula: see text]T) = R + 2f(T) model given by [T. Harko et al., Phys. Rev. D 84, 024020 (2011)] with cosmological term. Also, we have obtained General Relativity (GR) solutions for MSQM distributions. For [Formula: see text], we get the dark energy model, i.e. [Formula: see text], [Formula: see text] and [Formula: see text]. However, for [Formula: see text], we find the cosmological constant [Formula: see text] as negative in f(R,[Formula: see text]T) theory and GR. These results agree with [S. Aygün et al., Astrophys. Space Sci. 361, 380 (2016); C. Aktaş and S. Aygün, Chinese J. Phys. 55, 71 (2017); P. K. Sahoo et al., Mod. Phys. Lett. A 32, 1750105 (2017)] in f(R,[Formula: see text]T) theory. The physical consequences of our obtained models are discussed at the end.

LRS Bianchi type-I cosmological model with constant deceleration parameter in f(R,T) gravity

A spatially homogeneous anisotropic LRS Bianchi type-I cosmological model is studied in [Formula: see text] gravity with a special form of Hubble's parameter, which leads to constant deceleration parameter. The parameters involved in the considered form of Hubble parameter can be tuned to match, our models with the [Formula: see text]CDM model. With the present observed value of the deceleration parameter, we have discussed physical and kinematical properties of a specific model. Moreover, we have discussed the cosmological distances for our model.