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arXiv · 1712.01075

Model independent constraints on transition redshift

J. F. Jesus·R. F. L. Holanda·S. H. Pereira
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Abstract

This paper aims to put constraints on the transition redshift $z_t$, which determines the onset of cosmic acceleration, in cosmological-model independent frameworks. In order to perform our analyses, we consider a flat universe and {assume} a parametrization for the comoving distance $D_C(z)$ up to third degree on $z$, a second degree parametrization for the Hubble parameter $H(z)$ and a linear parametrization for the deceleration parameter $q(z)$. For each case, we show that {type Ia supernovae} and $H(z)$ data complement each other on the parameter {space} and tighter constrains for the transition redshift are obtained. By {combining} the type Ia supernovae observations and Hubble parameter measurements it is possible to constrain the values of $z_t$, for each approach, as $0.806\pm 0.094$, $0.870\pm 0.063$ and $0.973\pm 0.058$ at 1$σ$ c.l., respectively. Then, such approaches provide cosmological-model independent estimates for this parameter.

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J. F. Jesus, R. F. L. Holanda, S. H. Pereira. 2018-05-30. Model independent constraints on transition redshift. https://doi.org/10.1088/1475-7516%2F2018%2F05%2F073

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