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Cosmological constraints from lensing statistics and supernovae on the cosmic equation of state

Ioav Waga·Ana Paula M. R. Miceli
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Abstract

We investigate observational constraints from lensing statistics and high-z type Ia supernovae on flat cosmological models with nonrelativistic matter and an exotic fluid with equation of state, $p_x=(m/3 -1)ρ_x$. We show that agreement with both tests at the 68% confidence level is possible if the parameter $m$ is low ($m \lesssim 0.85$) and $0.24 \lesssim Ω_{m0} \lesssim 0.38$ with lower values of $Ω_{m0}$ corresponding to higher $m$. We find that a conventional cosmological constant model with $Ω_{m0}\simeq 0.33$ is the best fit model of the combined likelihood.

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Ioav Waga, Ana Paula M. R. Miceli. 1998-11-30. Cosmological constraints from lensing statistics and supernovae on the cosmic equation of state. https://doi.org/10.1103/physrevd.59.103507

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