Test of the cosmic evolution using Gaussian processes

Abstract

Much focus was on the possible slowing down of cosmic acceleration under the dark energy parametrization. In the present paper, we investigate this subject using the Gaussian processes (GP), without resorting to a particular template of dark energy. The reconstruction is carried out by abundant data including luminosity distance from Union2, Union2.1 compilation and gamma-ray burst, and dynamical Hubble parameter. It suggests that slowing down of cosmic acceleration cannot be presented within 95% C.L., in considering the influence of spatial curvature and Hubble constant. In order to reveal the reason of tension between our reconstruction and previous parametrization constraint for Union2 data, we compare them and find that slowing down of acceleration in some parametrization is only a "mirage". Although these parameterizations fits well with the observational data, their tension can be revealed by high order derivative of distance D. Instead, GP method is able to faithfully model the cosmic expansion history.

Hubble Parameter Measurement Constraints on the Redshift of the Deceleration–acceleration Transition, Dynamical Dark Energy, and Space Curvature

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The Cardassian expansion revisited: constraints from updated Hubble parameter measurements and type Ia supernova data

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Gaussian processes reconstruction of dark energy from observational data

“…In the present paper, we use the 30 cosmic chronometer data points which compiled in Table 1 of Ref. [67], because the latter method is model-dependent. An underlying cosmology is needed to calculate the sound horizon in the latter method.…”