Crossing of the phantom divide using tachyon-Gauss-Bonnet gravity

Abstract

In this paper we consider two models. First, we study tachyon-Gauss-Bonnet gravity and obtain the condition of the equation of state crossing $\ensuremath{-}1$. Second, we discuss the modified Gauss-Bonnet gravity with the tachyon field and show the condition of $\ensuremath{\omega}$ crossing $\ensuremath{-}1$. Also, we plot figures for $\ensuremath{\omega}$ numerically in special potential and coupling function.