Interacting Tsallis holographic dark energy in $q$-modified DGP braneworld

Abstract

We explore the cosmological aspects of interacting Tsallis holographic dark energy (THDE) in a $q$-modified DGP braneworld setup emerging from non-Gaussian statistical mechanics.To this end, three classes of superstatistics, that is, log-normal, inverse $\chi^2$ and $\chi^2$ superstatistics were incorporated into the model. We examined the implication of the three superstatistics on different cosmological parameters, namely, the dimensionless energy density and the equation-of-state (EoS) of THDE, along with the deceleration parameter and the squared speed of sound. As a result, we noted that the cosmological parameters stemming from the $\chi^2$ superstatistics, with a parameter $q > 1$, represent the highest deviation from those ascribed to the standard DGP model. While the system parameters show appropriate behavior in all three cases, the model cannot achieve stability throughout the history of the Universe. It is probably the outcome of setting the Hubble horizon as the infrared cutoff. Furthermore, the behavior of EoS was found to be governed by the value of the THDE parameter ${\delta}$. That is to say, for ${\delta} > 2$ THDE exhibits a phantom-like behavior while for ${\delta} < 2$ it displays a quintessence behavior. Constrained by the dominant energy condition, an upper bound on ${\delta}$ $({\delta} < 2)$ has been imposed.