Tracking quintessence by cosmic shear - Constraints from VIRMOS-
Descart and CFHTLS and future prospects
Carlo SCHIMD
CEA
Résumé :
Among several descriptions of the dark energy, a quintessence
scalar field provides a simple, well-defined alternative to cosmological
constant able to account for the dynamics of the universe at low and
high redshift. After showing the advantages of such a realization of the
dark energy with respect to parametrizations of its equation of state, I
present recent results based on a cosmic shear analysis, for the first
time using VIRMOS-Descart and CFHTLS data to investigate such kind of
models. Several questions about the constraints on dark energy come out,
notably the relevance of a proper description of the non-linear regime
of structures formation, the caution needed when combining with other
cosmological observables such as SnIa and CMB, the dependence on
systematics, for instance the accuracy of photometric redshift or
luminosity distance measurements. Finally, I will discuss the usefulness
of (space-based) wide surveys to study the dark energy sector.
