We propose a multifield extension of (generalized) G inflation, based on covariant multi-Galileons and their generalization preserving second-order field equations. We compute the quadratic action for cosmological perturbations. By comparing the formulas for cosmological perturbations, it is highlighted that multifield Dirac-Born-Infield Galileon inflation is not included in the multifield version of generalized G inflation. Our result indicates that the generalized covariant multi-Galileon theory is not the most general multi-scalar-tensor theory with second-order field equations.
|Journal||Physical Review D - Particles, Fields, Gravitation and Cosmology|
|Publication status||Published - Oct 8 2013|
All Science Journal Classification (ASJC) codes
- Nuclear and High Energy Physics
- Physics and Astronomy (miscellaneous)