Late time cosmological dynamics with a nonminimal extension of the mimetic matter scenario
Department of Physics, Faculty of Basic Sciences, University of Mazandaran, P. O. Box 47416-95447, Babolsar, Iran
* e-mail: firstname.lastname@example.org
Accepted: 13 January 2018
Published online: 13 February 2018
We investigate an extension of mimetic gravity in which mimetic matter is nonminimally coupled to the Ricci scalar. We derive the background field equations and show that, as the minimal case, the nonminimal mimetic matter can behave as dark matter or dark energy. By adopting some well-known potentials, we study the dynamics of the scale factor and the equation of state parameter in detail. As the effective mimetic dark energy, this model explains the late time cosmic acceleration and its equation of state parameter crosses the phantom divide. We extend our analysis to the dynamical system approach and the phase space trajectories of the model. We obtain an attractor line which corresponds to the late time cosmic acceleration. By comparing this nonminimal mimetic matter scenario with observational data for the LCDM, we show that the confidence levels of this model overlap with those of Planck 2015 TT, TE, EE + Low P + Lensing + BAO data in the LCDM model.
© Società Italiana di Fisica and Springer-Verlag GmbH Germany, part of Springer Nature, 2018