A plausible upper limit on the number of e-foldings
arXiv:hep-th/0308145 · doi:10.1103/PhysRevD.69.104014
Abstract
Based solely on the arguments relating Friedmann equation and the Cardy formula we derive a bound for the number of e-folds during inflation for a standard Friedmann-Robertson-Walker as well as non-standard four dimensional cosmology induced by a Randall-Sundrum-type model.
4 pages. Version appearing in the Physical Review D