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تسجيل مستخدم جديدModel-independent determination of cosmic curvature based on Pad{e} approximation
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Given observations of the standard candles and the cosmic chronometers, we apply Pad{e} parameterization to the comoving distance and the Hubble paramter to find how stringent the constraint is set to the curvature parameter by the data. A weak informative prior is introduced in the modeling process to keep the inference away from the singularities. Bayesian evidence for different order of Pad{e} parameterizations is evaluated during the inference to select the most suitable parameterization in light of the data. The data we used prefer a parameterization form of comoving distance as $D_{01}(z)=frac{a_0 z}{1+b_1 z}$ as well as a competitive form $D_{02}(z)=frac{a_0 z}{1+b_1 z + b_2 z^2}$. Similar constraints on the spatial curvature parameter are established by those models and given the Hubble constant as a byproduct: $Omega_k = 0.25^{+0.14}_{-0.13}$ (68% confidence level [C.L.]), $H_0 = 67.7 pm 2.0$ km/s/Mpc (68% C.L.) for $D_{01}$, and $Omega_k = -0.01 pm 0.13$ (68% C.L.), $H_0 = 68.8 pm 2.0$ km/s/Mpc (68% C.L.) for $D_{02}$. The evidence of different models demonstrates the qualitative analysis of the Pad{e} parameterizations for the comoving distance.
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