Galileons, phantom fields, and the fate of the Universe

Abstract

In this paper we study cosmological dynamics of phantom as well as non-phantom fields with linear potential in presence of Galileon correction $(\partial_\mu\phi \partial^\mu\phi) \Box \phi$. We show that the Big Crunch singularity is delayed compared to the standard case; the delay crucially depends upon the strength of Galileon correction. As for the phantom Galileon, $\rho_{\phi}$ is shown to grow more slowly compared to the standard phantom delaying the approach to singularity. In case, $V\sim \phi^n, n>4$, Big Rip is also delayed, similar phenomenon is shown to take place for potentials steeper than the exponential.