Constant Roll Inflation in Viscous Mimetic Matter-Geomerty Coupling Gravity

摘要

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+αR2+βTγdocumentclass12pt{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepackage{amsbsy} usepackage{mathrsfs} usepackage{upgreek} setlength{oddsidemargin}{-69pt} begin{document}$$f(R,T) = R +alpha R^2+beta T^{gamma }$$end{document} 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 nsdocumentclass12pt{minimal} usepackage{amsmath} usepackage{wasysym} usepackage{amsfonts} usepackage{amssymb} usepackage{amsbsy} usepackage{mathrsfs} usepackage{upgreek} setlength{oddsidemargin}{-69pt} begin{document}$$n_s$$end{document}. A comparison of these results with observational data shows that our model can be used to describe the accelerated expansion of the universe.