Constant Roll Inflation in Viscous Mimetic Matter-Geomerty Coupling Gravity

Abstract

We investigate in this work, the inflationary scenario in viscous f(R, T) gravity formalism with mimetic potential and Lagrange multiplier. Considering that our universe contains beside a perfect fluid, a dark energy and a bulk viscous fluid, we obtain through the modified Friedmann equations a main differential equation that may describe the cosmological evolution in viscous mimetic f(R, T) gravity. For particular choice of the model \(f(R,T) = R +\alpha R^2+\beta T^{\gamma }\) and for two forms of bulk viscosity coefficient, one as function of the Hubbe parameter H(t) and the other, as density dependent viscosity, we present a numerical results of the inflationary parameters such as the tensor-to-scalar ratio r and the scalar spectral index \(n_s\). A comparison of these results with observational data shows that our model can be used to describe the accelerated expansion of the universe.