Galileons on cosmological backgrounds

  title={Galileons on cosmological backgrounds},
  author={Garrett Goon and Kurt Hinterbichler and Mark Trodden},
  journal={Journal of Cosmology and Astroparticle Physics},
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… 

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