Quantum Stability of Chameleon Field Theories
  Chameleon scalar fields are dark energy candidates which suppress fifth
forces in high density regions of the universe by becoming massive. We consider
chameleon models as effective field theories and estimate quantum corrections
to their potentials. Requiring that quantum corrections be small, so as to
allow reliable predictions of fifth forces, leads to an upper bound $m < 0.0073
(\rho / 10 {\rm g\, cm}^{-3})^{1/3}$eV for gravitational strength coupling
whereas fifth force experiments place a lower bound of $m>0.0042$\,eV. An
improvement of less than a factor of two in the range of fifth force
experiments could test all classical chameleon field theories whose quantum
corrections are well-controlled and couple to matter with nearly gravitational
strength regardless of the specific form of the chameleon potential.
