Observational constraint on interacting Tsallis holographic dark energy in logarithmic Brans-Dicke theory

TL;DR

This paper explores Tsallis holographic dark energy within logarithmic Brans-Dicke theory, analyzing its behavior, stability, and consistency with observations, for both interacting and non-interacting dark sectors.

Contribution

It introduces a novel model of holographic dark energy in Brans-Dicke theory with a logarithmic scalar field, including stability analysis and observational comparison.

Findings

Models exhibit accelerated expansion consistent with observations

Stability analysis shows models are stable under perturbations

Cosmological parameters align with current observational data

Abstract

In this paper, we investigate the dark energy phenomenon by studying the Tsallis holographic dark energy within the framework of Brans-Dicke (BD) scalar-tensor theory of gravity [Phys. Rev. \textbf{124}, 925 (1961)]. In this context, we choose the BD scalar field $\phi$ as a logarithmic function of the average scale factor $a(t)$ and Hubble horizon as the IR cutoff ($L=H^{-1}$). We reconstruct two cases of non-interacting and interacting fluid (dark sectors of cosmos) scenario. The physical behavior of the models are discussed with the help of graphical representation to explore the accelerated expansion of the universe. Moreover, the stability of the models are checked through squared sound speed $v_s^2$. The well-known cosmological plane i.e., $\omega_{de}-\omega^{\prime}_{de}$ is constructed for our models. We also include comparison of our findings of these dynamical parameters with observational constraints. It is also quite interesting to mention here that the results of deceleration, equation of state parameters and $\omega_{de}-\omega^{\prime}_{de}$ plane coincide with the modern observational data.