Cosmological evolution of α and μ and the dynamics of dark energy

P. P. Avelino

Abstract
We study the cosmological evolution of the fine structure constant and the proton-to-electron mass ratio in the context of a generic class of models, where the gauge kinetic function is a linear function of a quintessence-type real scalar field described by a Lagrangian with a standard kinetic term and a scalar field potential . We further assume that the scalar field potential is a monotonic function of and that the scalar field is always rolling down the potential. We show that, for this class of models, low-redshift constraints on the evolution of and can provide very stringent limits on the corresponding variations at high redshift. We also demonstrate that these limits may be relaxed by considering more general models for the dynamics of and . However, in this case, the ability to reconstruct the evolution of the dark energy equation of state using varying couplings could be seriously compromised.

Physical Review D
Volume 78, Page 043516
August 2008

>> ADS>> DOI