Fine tuning in quintessence models with exponential potentials

Nenhuma Miniatura disponível




França, Urbano [UNESP]
Rosenfeld, Rogério [UNESP]

Título da Revista

ISSN da Revista

Título de Volume



We explore regions of parameter space in a simple exponential model of the form V = V0 e-λ(Q/Mp) that are allowed by observational constraints. We find that the level of fine tuning in these models is not different from more sophisticated models of dark energy. We study a transient regime where the parameter λ has to be less than √3 and the fixed point ΩQ = 1 has not been reached. All values of the parameter λ that lead to this transient regime are permitted. We also point out that this model can accelerate the universe today even for λ > √2, leading to a halt of the present acceleration of the universe in the future thus avoiding the horizon problem. We conclude that this model can not be discarded by current observations. © SISSA/ISAS 2002.



Cosmology of Theories beyond the SM, Physics of the Early Universe

Como citar

Journal of High Energy Physics, v. 6, n. 10, p. 315-329, 2002.