Detecting dark energy in orbit: The cosmological chameleon

  title={Detecting dark energy in orbit: The cosmological chameleon},
  author={P. Brax and C. V. D. Bruck and A. Davis and J. Khoury and A. Weltman},
  journal={Physical Review D},
We show that the chameleon scalar field can drive the current phase of cosmic acceleration for a large class of scalar potentials that are also consistent with local tests of gravity. These provide explicit realizations of a quintessence model where the quintessence scalar field couples directly to baryons and dark matter with gravitational strength. We analyze the cosmological evolution of the chameleon field and show the existence of an attractor solution with the chameleon following the… Expand
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