7 research outputs found
Archeops results
\Archeops is a balloon--borne instrument dedicated to measuring cosmic
microwave background (CMB) temperature anisotropies at high angular resolution
( 12 arcmin.) over a large fraction (30%) of the sky in the
(sub)millimetre domain (from 143 to 545 GHz). We describe the results obtained
during the last flight: the \Archeops estimate of the CMB angular power
spectrum linking for the first time \Cobe scales and the first acoustic peak,
consequences in terms of cosmological parementers favouring a flat-
Universe. We also present the first measurement of galactic dust polarization
and accurate maps of the galactic plane diffuse (sub) millimetre emisson.Comment: 8 pages, 6 figures, to appear in C.R. Physiqu
Vector field as a quintessence partner
We derive generic equations for a vector field driving the evolution of flat
homogeneous isotropic universe and give a comparison with a scalar filed
dynamics in the cosmology. Two exact solutions are shown as examples, which can
serve to describe an inflation and a slow falling down of dynamical
``cosmological constant'' like it is given by the scalar quintessence. An
attractive feature of vector field description is a generation of ``induced
mass'' proportional to a Hubble constant, which results in a dynamical
suppression of actual cosmological constant during the evolution.Comment: 14 pages, LaTeX file, iopart class, discussion extended, reference
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