Particle Production Scenario in an Algebraically Coupled Quintessence Field with a Dark Matter Fluid

TL;DR

This paper explores a coupled quintessence model with dark matter, analyzing particle production, system dynamics, and data fitting, proposing a viable alternative to the standard cosmological model based on statistical criteria.

Contribution

It introduces an algebraically coupled quintessence-dark matter model with exponential interaction, analyzing its dynamics and fitting it to observational data, showing its competitiveness with ΛCDM.

Findings

Model fits observational data well.

One model is a strong ΛCDM alternative based on AIC and BIC.

System exhibits additional pressure due to particle creation.

Abstract

We investigate the dynamics of an algebraically coupled quintessence field with a dark matter fluid, focusing on particle production through the action principle via a modified interaction Lagrangian. The interaction parameter serves as the source of dark matter particle production and entropy generation. As particle creation occurs due to the interaction between the field and fluid sectors, the system exhibits additional pressure. Our analysis includes studying the system's dynamics by considering an exponential type of interaction corresponding to the field's exponential potential. We assess the system's background dynamics using the dynamical system stability technique to derive the constraints on the model parameters. Additionally, we determine the best-fit values of the model parameters against two combinations of data sets: (i) CC+Pantheon+SH0ES, and (ii) CC+Pantheon+SH0ES+SDSS BAO+ DESI BAO. By employing a comprehensive data analysis technique, we compare the evidence of our models to flat $\Lambda$CDM. Based on the Akaike Information Criterion (AIC) and Bayesian Information Criterion (BIC), one of the models emerges as a robust alternative to $\Lambda$CDM when considering the joint data sets.