2016/09/11 by V. K. Oikonomou · 21 citations
Physics and Astronomy · #Acceleration #Black Holes and Theoretical Physics #Context (archaeology) #Cosmology and Gravitation Theories #Dark energy #Equation of state #Exponential function #Exponential growth #Gravitation #Noncommutative and Quantum Gravity Theories #Unification #gr-qc
paper · pdf · doi:10.1142/s0217732316501911
published in Modern Physics Letters A 31(33), 1650191 (World Scientific) · MPLA accepted
arxiv created 2016/09/11 · openalex created_date 2016/09/23 · openalex publication_date 2016/10/05 · arxiv updated 2016/10/06 · openalex updated_date 2026/08/05
We demonstrate how to describe in an unified way early and late-time acceleration in the context of mimetic F(R) gravity. As we show, an exponential F(R) gravity model has appealing features, with regard to unification and we perform an analysis of the late-time evolution. The resulting picture is interesting since in the mimetic case, certain pathologies of some ordinary F(R) models are remedied in a consistent way, owing to the presence of the mimetic potential and the Lagrange multiplier. We quantify the late-time evolution analysis by studying the scaled dark energy density, the dark energy equation of state and the total effective equation of state, and as we show the late-time evolution is crucially affected by the functional form of the F(R) gravity. It is intriguing that the most appealing case corresponds to the exponential F(R) gravity which unifies late- and early-time acceleration. Finally, we study the behavior of the effective gravitational constant and the growth factor, and as we show, significant differences between the mimetic and ordinary F(R) exponential model are spotted in the growth factor.