Modeling cosmic acceleration with a generalized varying deceleration parameter

TL;DR

This paper proposes a generalized variable deceleration parameter model to explain cosmic acceleration, constrained by recent observational data, and confirms its stability and consistency with cosmological observations.

Contribution

It introduces a new parametrization of the deceleration parameter that aligns with thermodynamic constraints and observational data, enhancing understanding of cosmic acceleration.

Findings

Model fits observational data well

Estimated transition redshift consistent with observations

Model remains stable under perturbations

Abstract

Understanding the accelerating expansion of the Universe remains a fundamental challenge in modern cosmology. In this paper, we investigate a cosmological model parametrized by a generalized variable deceleration parameter to elucidate the dynamics driving cosmic acceleration. By employing constraints from the latest observational datasets, including Cosmic Chronometers (CC), Type Ia Supernovae (SNe), and Baryon Acoustic Oscillations (BAO), we assess the compatibility of the model with observational data. The chosen parametrization aligns with thermodynamic constraints on the deceleration parameter, further validating its reliability. Further, we estimate the present value of the Hubble parameter, transition redshift, deceleration parameter, and EoS parameter, which align with observational data. Lastly, our stability analysis confirms the model's stability against small perturbations.