Transient cosmic acceleration

Abstract

We explore cosmological consequences of two quintessence models in which the current cosmic acceleration is a transient phenomenon. We argue that one of them (in which the EoS parameter switches from freezing to thawing regimes) may reconcile the slight preference of observational data for freezing potentials with the impossibility of defining observables in String/M-theory due to the existence of a cosmological event horizon in asymptotically de Sitter universes.

Comments: 6 pages, 3 figures, IAU 2009 JD9 conference proceedings. MmSAIt, vol.80 (in press). Eds. Paolo Molaro & Elisabeth Vangioni