Observational constraints on power-law cosmologies - art. no. 043514.

Citation
M. Kaplinghat et al., Observational constraints on power-law cosmologies - art. no. 043514., PHYS REV D, 5904(4), 1999, pp. 3514
Citations number
30
Categorie Soggetti
Physics
Journal title
PHYSICAL REVIEW D
ISSN journal
05562821 → ACNP
Volume
5904
Issue
4
Year of publication
1999
Database
ISI
SICI code
0556-2821(19990215)5904:4<3514:OCOPC->2.0.ZU;2-#
Abstract
In a class of models designed to solve the cosmological constant problem by coupling scalar or tensor classical fields to the space-time curvature, th e universal scale factor grows as a power law in the age, a proportional to t(alpha), regardless of the matter content or cosmological epoch. We inves tigate constraints on such "power-law cosmologies" from the present age of the Universe, the magnitude-redshift relation, and from primordial nucleosy nthesis. Constraints from the current age of the Universe and from the high -redshift supernovae data require "large" alpha (approximate to 1), while c onsistency with the inferred primordial abundances of deuterium and helium- 4 forces alpha to lie in a very narrow range around a lower value (approxim ate to 0.55). Inconsistency between these independent cosmological constrai nts suggests that such power-law cosmologies are not viable. [S0556-2821(99 )02304-8].