Unified description of screened modified gravity.

  title={Unified description of screened modified gravity.},
  author={Philippe Brax and A. C. Davis and Baojiu Li and Hans A. Winther},
  journal={Physical Review D},
We consider modified gravity models driven by a scalar field whose effects are screened in high density regions due to the presence of nonlinearities in its interaction potential and/or its coupling to matter. Our approach covers chameleon, f(R) gravity, dilaton and symmetron models and allows a unified description of all these theories. We find that the dynamics of modified gravity are entirely captured by the time variation of the scalar field mass and its coupling to matter evaluated at the… 

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