Observational constraints on New Tsallis holographic energy in Rastall theory

TL;DR

This paper investigates the cosmological implications of New Tsallis holographic dark energy within Rastall theory, using observational data to constrain parameters and compare with the standard b3CDM model, highlighting its viability and testable deviations.

Contribution

It introduces a combined model of NTHDE and Rastall theory, providing new constraints and demonstrating its compatibility with current data and potential for future observational tests.

Findings

Model remains compatible with current observational data.

Predictions for H(z) are slightly more consistent with intermediate-redshift observations.

The combined NTHDE and Rastall model mimics the current dark energy density in b3CDM.

Abstract

The cosmological implications of New Tsallis holographic dark energy (NTHDE) in Rastall theory have been studied. Using the data set that includes DESI BAO (DR2), PantheonPlus SNe Ia, H(z) measurements, and BBN and the MCMC analysis, the key cosmological and model-specific parameters are constrained. The result is compared with that of the {\Lambda}CDM model indicating that in addition to providing a viable dynamical dark energy framework, predictions for H(z) are slightly more consistent with intermediate-redshift observations. Generally, the model remains compatible with current data and offers testable deviations from {\Lambda}CDM for upcoming surveys. It is also seen that when the energy density of quantum fields in vacuum, exposed by NTHDE, is combined with the Rastall correction term to the general relativity, a plausible candidate for dynamical dark energy is obtained that mimic the current value of the dark energy density parameter reported in the {\Lambda}CDM model. The latter cannot be repeated by NTHDE alone. The study also confirms previous theoretical and observational constraints on the Rastall parameter obtained by focusing on the thermodynamics, early universe, pulsars, and the early-type galaxies.