On the Covariant Galileon and a consistent self-accelerating Universe

Abstract

In this paper we show that the flat space Galilean theories with up to three scalars in the equation of motion (the quartic Galileons) are recovered in the decoupling limit of certain scalar theories non-minimally coupled to gravity, the so-called "Slotheonic" theories. These theories are also invariant under the generalized Galilean shifts in curved spacetime. While Galilean self-(derivative)couplings are not explicit in the action, they appear after integrating out gravity. We then argue that Galilean supersymmetric theories may only be found in the context of supergravity. Finally, we discuss on the possibility that Slotheonic theories are the effective four dimensional theories of consistent DGP-like models with self-accelerating cosmological solutions. Moreover, we show that the quartic and cubic Galileon in consistent DGP models cannot be decoupled.

v3: clarifications added; version accepted for publication in PRD

References in corpus (7)

• Covariant Galileon
• Generalized Galileons: All scalar models whose curved background extensions maintain second-order field equations and stress tensors
• Multi-field galileons and higher co-dimension branes
• UV-Protected Inflation
• Physics of Trans-Planckian Gravity
• Higher-derivative scalar-vector-tensor theories: black holes, Galileons, singularity cloaking and holography
• Gravitational Cheshire effect: Nonminimally coupled scalar fields may not curve spacetime

Cited by in corpus (13)

• DBI Galileons in the Einstein Frame: Local Gravity and Cosmology
• Dynamical analysis of generalized Galileon cosmology
• Cosmology with nonminimal kinetic coupling and a power-law potential
• Cosmology with non-minimal derivative couplings: perturbation analysis and observational constraints
• Self-unitarization of New Higgs Inflation and compatibility with Planck and BICEP2 data
• Bounce and cyclic cosmology in weakly broken galileon theories
• Electroweak vacuum stability and inflation via non-minimal derivative couplings to gravity
• Observational Viability of an Inflation Model with E-Model non-Minimal Derivative Coupling
• Late time acceleration in a slow moving galileon field
• Dynamical system analysis in modified Galileon cosmology
• Bounce and Collapse in the Slotheonic Universe
• Non-minimal derivative couplings and inflation in supergravity
• Ghosts in the self-accelerating DGP branch with Gauss-Bonnet effect