New Hubble parameter data and possibility of more than one deceleration–acceleration transition redshift

Abstract

AbstractIt is quite believed that Universe has undergone a smooth transition from a decelerated phase to its present accelerated phase of expansion. There exists a wide consensus, based on robust observational indicating transition redshift $$z_{tr}$$ z tr around the unity. However our analysis on complete collection of reliable Hubble parameter H(z) data at intermediate redshift $$0.07<z <2.36 $$ 0.07 < z < 2.36 , BAO, Pantheon data, give some hints that the universe may be transit more than one time from deceleration to acceleration phase in course of its evolution. Although we are agree with the results claimed by previous studies state the simplest cosmological models such as $$\Lambda CDM$$ Λ C D M and XCDM are consistent with Hubble data, but we doubt that they will be the best. We show that the chameleon cosmological model is more favored than the simple models and very well fits with the full Hubble data. Reconstructing the deceleration parameter based on best fitted parameters of the model indicates a new dynamic for the universe in which more than one transition occurs from deceleration to acceleration phase and the last transition occurs at $$z_{tr}\simeq .43\pm 0.04$$ z tr ≃ . 43 ± 0.04 which is close to that derived by the High-z Supernovae Search (HZSNS) team, $$z_{tr}=.43\pm 0.07$$ z tr = . 43 ± 0.07 (Riess et al. Astrophys. J. 659, 98–121, 2007).