General constraints on Tsallis holographic dark energy from observational data

TL;DR

This study tests the Tsallis holographic dark energy model against multiple observational datasets, finding it can slightly improve fit over standard cosmology and exploring the impact of matter-dark energy interaction.

Contribution

It introduces constraints on Tsallis holographic dark energy parameters using diverse observational data, including supernovae, Hubble measurements, and BAO, and considers matter-dark energy interaction effects.

Findings

Best-fit Hubble constant values are closer to local measurements.

The model slightly outperforms standard cosmology in data fitting.

Interaction between matter and dark energy is compatible with observations.

Abstract

We investigated Tsallis holographic dark energy (THDE) model in light of modern observations of supernovae, Hubble parameter measurements, data for baryon acoustic oscillations and fluctuations of matter density. The dark energy density for THDE model is written as $\rho_d = 3C^2 / L^{4-2\gamma}$ where $C$ and $\gamma$ are some constants. Scale $L$ is infrared cut-off lenght for which we use the event horizon. For analysis of type Ia supernovae (SNeIa) data Pantheon+ samples are involved. Dark Energy Spectroscopic Instrument (DESI) 2024 measurements serves as source of data about ratios between sound horizon $r_d$ and Hubble ($d_H$) or volume averaged ($d_V$) distances. The updated dataset of Hubble parameter for various redshift is also used in our analysis. Finally we considered the dependence of matter density fluctuations in past from redshift. The standard stratefy of $\chi^2$ minimizing allows to estimate the optimal values of parameters ($\Omega_{de}$ and $H_0$) for some fixed values of $C$ and $\gamma$. One note that best-fit values for parameters $H_0$ from Hubble parameter and SNeIa data are more close than in standard $\Lambda$CDM model for some $C$ and $\gamma$ although problem of Hubble tension remains unsolved. The combined data analysis also gives slightly better results in comparison with standard cosmology. We included in our consideration the possible interaction between matter and holographic component and estimated the acceptable interval of model parameters in this case.