1205.5266 (Ratbay Myrzakulov)

Dark Energy in F(R,T) Gravity    [PDF]

Ratbay Myrzakulov

As is well known, modified gravity theories play an important role in the modern cosmology. In particular, the well-known F(R) gravity is an useful tool to study dark energy phenomena motivated at a fundamental level, and find the exact models of dark energy as well as dark matter. In the present work, we study some generalizations of F(R) and F(T) gravity theories. At first, we briefly present the formalism of F(R) and F(T) theories. Then we consider one of their generalizations - the so-called F(R,T) theory. In particular, the point-like Lagrangian is explicitly presented. Based on this Lagrangian, the explicit equations of F(R,T) theory are found. For the particular model $F(R,T)=\mu R+\nu T,$ the corresponding exact solution are found. Furthermore, we consider the physical quantities corresponding to the exact solution, and find that for some values of the parameter, the expansion of our universe can be accelerated without invoking dark energy.

View original: http://arxiv.org/abs/1205.5266