Evolution of Dark Energy Perturbations in Scalar-Tensor Cosmologies

  title={Evolution of Dark Energy Perturbations in Scalar-Tensor Cosmologies},
  author={J. C. Bueno S{\'a}nchez and Leandros Perivolaropoulos},
  journal={Physical Review D},
We solve analytically and numerically the generalized Einstein equations in scalar-tensor cosmologies to obtain the evolution of dark energy and matter linear perturbations. We compare our results with the corresponding results for minimally coupled quintessence perturbations. We find that scalar-tensor dark energy density perturbations are amplified by a factor of about 10{sup 4} compared to minimally coupled quintessence perturbations on scales less than about 1000 h{sup -1} Mpc (sub-Hubble… 
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