Model-independent determination of the cosmic expansion rate
نویسندگان
چکیده
منابع مشابه
Model-independent determination of the cosmic expansion rate. I. Application to type-Ia supernovae
Aims. In view of the substantial uncertainties regarding the possible dynamics of the dark energy, we aim at constraining the expansion rate of the universe without reference to a specific Friedmann model and its parameters. Methods. We show that cosmological observables integrating over the cosmic expansion rate can be converted into a Volterra integral equation which is known to have a unique...
متن کاملModel independent constraints on the cosmological expansion rate
We investigate what current cosmological data tells us about the cosmological expansion rate in a model independent way. Specifically, we study if the expansion was decelerating at high redshifts and is accelerating now, without referring to any model for the energy content of the universe, nor to any specific theory of gravity. This differs from most studies of the expansion rate which, e.g., ...
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ژورنال
عنوان ژورنال: Astronomy & Astrophysics
سال: 2008
ISSN: 0004-6361,1432-0746
DOI: 10.1051/0004-6361:20078983