Does really be in tension with the Hubble diagram data?
Abstract
In this article, we elaborate further on the "tension", suggested recently by the authors Lusso:2019akb,Risaliti:2018reu. We combine Supernovae type Ia (SNIa) with quasars (QSO) and Gamma Ray Bursts (GRB) data in order to reconstruct a model independent Hubble diagram to as high redshifts as possible. Specifically, in the case of either SNIa or SNIa/QSO data, we find that current values of the cosmokinetic parameters extracted from the Gaussian process are consistent with those of . Including GRBs, in the analysis, we find a tension, which however is not as significant as that mentioned in Lusso:2019akb, Risaliti:2018reu. Finally, we argue that the choice of the kernel function used in extracting the luminosity distance might affect the amount of tension.