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Scalar-field quintessence by cosmic shear: CFHT data analysis and forecasts for DUNE

Carlo Schimd·Ismael Tereno
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Abstract

A light scalar field, minimally or not-minimally coupled to the metric field, is a well-defined candidate for the dark energy, overcoming the coincidence problem intrinsic to the cosmological constant and avoiding the difficulties of parameterizations. We present a general description of the weak gravitational lensing valid for every metric theory of gravity, including vector and tensor perturbations for a non-flat spatial metric. Based on this description, we investigate two minimally-coupled scalar field quintessence models using VIRMOS-Descart and CFHTLS cosmic shear data, and forecast the constraints for the proposed space-borne wide-field imager DUNE.

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Carlo Schimd, Ismael Tereno. 2006-12-01. Scalar-field quintessence by cosmic shear: CFHT data analysis and forecasts for DUNE. https://doi.org/10.1088/1751-8113%2F40%2F25%2Fs69

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