Phantom Divide Crossing with General Non-minimal Kinetic Coupling

Abstract

We propose a model of dark energy consists of a single scalar field with a general non-minimal kinetic couplings to itself and to the curvature. We study the cosmological dynamics of the equation of state in this setup. The coupling terms have the form $\xi_{1} R f(\phi)\partial_{\mu}\phi\partial^{\mu}\phi$ and $\xi_{2} R_{\mu\nu}f(\phi)\partial^{\mu}\phi\partial^{\nu}\phi$ where $\xi_{1}$ and $\xi_{2}$ are coupling parameters and their dimensions depend on the type of function $f(\phi)$. We obtain the conditions required for phantom divide crossing and show numerically that a cosmological model with general non-minimal derivative coupling to the scalar and Ricci curvatures can realize such a crossing.