A new comparison between holographic dark energy and standard $$\\varLambda $$-cosmology in the context of cosmography method

Abstract

The cosmography method is a model-independent technique used to reconstruct the Hubble expansion of the Universe at low redshifts. In this method, using the Hubble diagrams from Type Ia Supernovae (SNIa) in Pantheon catalog, quasars and Gamma-Ray Bursts (GRB), we put observational constraints on the cosmographic parameters in holographic dark energy (HDE) and concordance $$\\varLambda $$\n Λ\n CDM models by minimizing the error function $$\\chi ^2$$\n \n χ\n 2\n \n based on the statistical Markov Chain Monte Carlo (MCMC) algorithm. Then, we compare the results of the models with the results of the model-independent cosmography method. Except for the Pantheon sample, we observe that there is a big tension between standard cosmology and Hubble diagram observations, while the HDE model remains consistent in all cases. Then we use different combinations of Hubble diagram data to reconstruct the Hubble parameter of the model and compare it with the observed Hubble data. We observe that the Hubble parameter reconstructed from the model-independent cosmography method has the smallest deviation from the Hubble data and the $$\\varLambda $$\n Λ\n CDM (HDE) model has the largest (middle) deviation, especially when we keep the observational data point $$226^{+8.0}_{-0.8}$$\n \n 226\n \n -\n 0.8\n \n \n +\n 8.0\n \n \n at redshift $$z=2.36$$\n \n z\n =\n 2.36\n \n in the analysis. On the contrary, in the redshift $$z <1$$\n \n z\n <\n 1\n \n , we see that the compatibility of $$\\varLambda $$\n Λ\n CDM cosmology and observation is even better than the model independent cosmography method.