1201.6192 (Md. Wali Hossain et al.)

Do Observations Favour Galileon Over Quintessence?    [PDF]

Md. Wali Hossain, Anjan A. Sen

We study the Galileon scalar field model arising as a decoupling limit of the
Dvali-Gababdaze-Porrati (DGP) construction for the late time acceleration of
the universe. The model has one extra Galileon correction term over and above
the standard kinetic and potential energy terms for a canonical quintessence
field. We aim to study whether the current observational data can distinguish
between this Galileon field and the quintessence field. Our study shows the
remarkable result that for potentials like linear, square or exponential, the
data prefers the Galileon model over quintessence field. It confirms that the
observable universe demands the inclusion of higher derivative Galileon
corrections in the standard quintessence scalar field models.

View original: http://arxiv.org/abs/1201.6192