Matching torsion Lambda - term with observations

Abstract

Taking into account a torsion field gives rise to a negative pressure contribution in cosmological dynamics and then to an accelerated behaviour of Hubble fluid. The presence of torsion has the same effect of a Lambda - term. We obtain a general exact solution which well fits the data coming from high - redshift supernovae and Sunyaev - Zeldovich/X - ray method for the determination of the cosmological parameters. On the other hand, it is possible to obtain observational constraints on the amount of torsion density. A dust dominated Friedmann behaviour is recovered as soon as torsion effects are not relevant.

14 pages, 3 figures, accepted for publication on Int. Journ. Mod. Phys. D