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arXiv · 1906.05668

Observational Tests of Gauss-Bonnet Like Dark Energy Model

Abstract

The consistency of some dynamical dark energy models based on Gauss-Bonnet invariant, ${\cal G}$, is studied compared with cosmological observational tests. The investigated models are modified form of Gauss Bonnet dark energy, MGB-DE and two other versions which are interacting MGB and $n_0$MGB. The energy density of proposed models are combinations of powers of the Hubble rate, H, and its time derivative. To inquire the performance of MGB dark energy models, we have used data analyzing methods and numerical solutions, in both background and perturbed levels, based on recent observational data from SNIa, Baryon Acoustic Oscillations (BAO), Hubble parameter, CMB data, and structure formation data surveys. Employing joint data sets and comparing the results to those of LCDM, show that all versions of MGB-DE predicts the expansion history and evolution of structures appropriately as well as $Λ$CDM. If we use pure late universe data set, we see that all models of MGB-DE are successful in recent epoch, and there is not any significant evidence against or in favor of $Λ$CDM, whereas for early universe, statistical results indicate a significantly better agreement for $Λ$CDM as compared to all versions of MGB-DE models.

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Z. Molavi, A. Khodam-Mohammadi. 2019-06-11. Observational Tests of Gauss-Bonnet Like Dark Energy Model. https://doi.org/10.1140/epjp%2Fi2019-12723-x

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