A symmetry of the spatially flat Friedmann equations with barotropic fluid
arXiv:1108.2102 · doi:10.1016/j.physletb.2011.08.018
Abstract
A string-inspired duality symmetry of the spatially flat Friedmann equations of general-relativistic cosmology is discussed and generalized, providing a map between exact solutions corresponding to different values of the barotropic index.
10 pages, no figures, to appear in Phys. Lett. B