https://doi.org/10.1140/epjc/s10052-018-6470-0
Regular Article - Theoretical Physics
Fab Four effective field theory treatment
1
Department of Physics and Astronomy, University of Sussex, Brighton, BN1 9QH, UK
2
Dubna State University, Universitetskaya str. 19, Dubna, 141982, Russia
* e-mail: B.Latosh@sussex.ac.uk
Received:
17
June
2018
Accepted:
20
November
2018
Published online:
3
December
2018
The article addresses the John interaction from Fab Four class of Horndeski models from the effective field theory point of view. Models with this interaction are heavily constrained by gravitational wave speed observations, so it is important to understand, if these constraints hold in the effective field theory framework. We show that John interaction induces new terms quadratic in curvature at the level of the effective (classical) action. These new terms generate additional low energy scalar and spin-2 gravitational degrees of freedom. Some of them have a non-vanishing decay width and some are ghosts. Discussion of these features is given.
© The Author(s), 2018
