Decaying Λ cosmologies and statistical properties of gravitational lenses
نویسندگان
چکیده
In this paper we investigate the statistical properties of gravitational lenses for models in which a cosmological term decreases with time as Λ ∝ a −m , where a is the scale factor and m is a parameter (0 ≤ m < 3). We show that for given low values of the present matter density parameter Ω m0 , there is a wide range of values for m for which the lensing rate is significantly smaller than that in cosmological constant (Λ) models. We also show that models with low Ω m0 and m > ∼ 2 have high likelihood to reproduce the observed lens statistics in the HST snapshot survey.
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