# Galileons on cosmological backgrounds

@article{Goon2011GalileonsOC, title={Galileons on cosmological backgrounds}, author={Garrett Goon and Kurt Hinterbichler and Mark Trodden}, journal={Journal of Cosmology and Astroparticle Physics}, year={2011}, volume={2011}, pages={004-004} }

We construct four-dimensional effective field theories of a generalized DBI galileon field, the dynamics of which naturally take place on a Friedmann-Robertson-Walker spacetime. The theories are invariant under non-linear symmetry transformations, which can be thought of as being inherited from five-dimensional bulk Killing symmetries via the probe brane technique through which they are constructed. The resulting model provides a framework in which to explore the cosmological role that…

## 26 Citations

On the flat spacetime Galileons and the Born–Infeld type structures

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- 2015

We show how the flat spacetime Galileon field theories (FSGFT) in arbitrary dimensions can be obtained through a Born–Infeld (BI) type structure. This construction involves a brane metric and…

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We further develop the framework for coupling galileons and Dirac-Born-Infeld (DBI) scalar fields to a massive graviton while retaining both the non-linear symmetries of the scalars and ghost-freedom…

Covariant Master Theory for Novel Galilean Invariant Models and Massive Gravity

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Coupling the galileons to a curved background has been a tradeoff between maintaining second order equations of motion, maintaining the galilean shift symmetries, and allowing the background metric…

DBI Galileon and Late time acceleration of the universe

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We consider 1+3 dimensional maximally symmetric Minkowski brane embedded in a 1+4 dimensional maximally symmetric Minkowski background. The resulting 1+3 dimensional effective field theory is of DBI…

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The pseudo-conformal universe is an alternative to inflation in which the early universe is described by a conformal field theory on approximately flat space-time. The fields develop time-dependent…

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In the Horndeski's most general scalar-tensor theories with second-order field equations, we derive the conditions for the avoidance of ghosts and Laplacian instabilities associated with scalar,…

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We perform a detailed dynamical analysis of generalized Galileon cosmology, incorporating also the requirements of ghost and instabilities absence. We find that there are not any new stable late-time…

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In this paper we study the evolution of a spherical matter overdensity in the context of the recently introduced Galileon field theory. Our analysis considers the complete covariant Lagrangian in…

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