Early-universe constraints on dark energy - art. no. 103508

Citation
R. Bean et al., Early-universe constraints on dark energy - art. no. 103508, PHYS REV D, 6410(10), 2001, pp. 3508
Citations number
49
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Physics
Journal title
PHYSICAL REVIEW D
ISSN journal
0556-2821 → ACNP
Volume
6410
Issue
10
Year of publication
2001
Database
ISI
SICI code
0556-2821(20011115)6410:10<3508:ECODE->2.0.ZU;2-T
Abstract
In the past years "quintessence" models have been considered which can prod uce the accelerated expansion in the universe suggested by recent astronomi cal observations. One of the key differences between quintessence and a cos mological constant is that the energy density in quintessence, could be a s ignificant fraction of the overall energy even in the early universe, while the cosmological constant will be dynamically relevant only at late times. We use standard big bang nucleosynthesis and the observed abundances of pr imordial nuclides to put constraints on Omega (phi) at temperatures near T similar to1 MeV. We point out that current experimental data do not support the presence of such a field, providing the strong constraint Omega (phi) (MeV)<0.045 at 2<sigma> C.L. and strengthening previous results. We also co nsider the effect a scaling field has on cosmic microwave background (CMB) anisotropies using the recent data from BOOMERANG and DASI combined with SN Ia data, providing the CMB constraint Omega (phi)less than or equal to0.39 at 2 sigma during the radiation dominated epoch.