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Inflation in mimetic $f(R,T)$ gravity

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 نشر من قبل Snehasish Bhattacharjee
 تاريخ النشر 2021
  مجال البحث فيزياء
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In this paper, we employ mimetic $f(R,T)$ gravity coupled with Lagrange multiplier and mimetic potential to yield viable inflationary cosmological solutions consistent with latest Planck and BICEP2/Keck Array data. We present here three viable inflationary solutions of the Hubble parameter ($H$) represented by $H(N)=left(A exp beta N+B alpha ^Nright)^{gamma }$, $H(N)=left(A alpha ^N+B log Nright)^{gamma }$, and $H(N)=left(A e^{beta N}+B log Nright)^{gamma }$, where $A$, $beta$, $B$, $alpha$, $gamma$ are free parameters, and $N$ represents the number of e-foldings. We carry out the analysis with the simplest minimal $f(R,T)$ function of the form $f(R,T)= R + chi T$, where $chi$ is the model parameter. We report that for the chosen $f(R,T)$ gravity model, viable cosmologies are obtained compatible with observations by conveniently setting the Lagrange multiplier and the mimetic potential.

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