A look into the cosmological consequences of a dark energy model with higher derivatives of $H$ in the framework of Chameleon Brans-Dicke Cosmology

TL;DR

This paper explores the cosmological implications of a dark energy model with higher derivatives of the Hubble parameter within Chameleon Brans-Dicke cosmology, analyzing key parameters and their observational consistency.

Contribution

It introduces a specific dark energy model with higher derivatives of H in Chameleon Brans-Dicke cosmology and derives its cosmological parameters and behaviors.

Findings

Derived expressions for EoS parameters, pressure, and deceleration parameter.

Analyzed statefinder, cosmographic parameters, and sound speed for different cosmic epochs.

Compared model predictions with observational data.

Abstract

In this paper, we study some relevant cosmological features of a Dark Energy (DE) model with Granda-Oliveiros cut-off, which is just a specific case of Nojiri-Odintsov holographic DE unifying phantom inflation with late-time acceleration, in the framework of Chameleon Brans-Dicke (BD) Cosmology. Choosing a particular ansatz for some of the quantities involved, we derive the expressions of some important cosmological quantities, like the Equation of State (EoS) parameter of DE $w_D$, the effective EoS parameter $w_{eff}$, the pressure of DE $p_D$ and the deceleration parameter $q$. Moreover, we study the behavior of statefinder parameters $r$ and $s$, of the cosmographic parameters $j$, $s_{cosmo}$, $l$ and $m$ and of the squared speed of the sound $v_s^2$ for both case corresponding to non interacting and interacting Dark Sectors. We also plot the quantities we have derived and we calculate their values for $t\rightarrow 0$ (i.e. for the beginning of the Universe history), for $t\rightarrow \infty$ (i.e. for far future) and for the present time, indicated with $t_0$. The EoS parameters have been tested against various observational values available in the literature.