Galileon gravity and its relevance to late time cosmic acceleration

Understand

We consider the covariant galileon gravity taking into account the third order and fourth order scalar field Lagrangians L_3(\pi) and L_4(\pi) consisting of three and four $\pi$'s with four and five derivatives acting on them respectively.

• The background dynamical equations are set up for the system under consideration and the stability of the self accelerating solution is demonstrated in general setting.
• We extended this study to the general case of the fifth order theory.
• For spherically symmetric static background, we spell out conditions for suppression of fifth force effects mediated by the galileon field $\pi$.