Observational Evidence to Logistic Dark Energy Driving the Accelerating Universe

TL;DR

This paper introduces a logistic dark energy model where the dark energy density evolves via a logistic function, successfully explaining late-time cosmic acceleration and fitting observational data better than the standard $\\Lambda$CDM model.

Contribution

The paper proposes a novel logistic dark energy model with a dynamic equation of state, demonstrating its observational viability and potential to resolve the Hubble tension.

Findings

LDEM fits observational data better than $\\Lambda$CDM according to BIC.

The model's $w_D$ transitions from -1 to -0.76 over cosmic time.

Hubble constant estimates align with CMB predictions.

Abstract

We present logistic dark energy model (LDEM), where the dark energy density follows a logistic function for the scale factor. The equation of state parameter of dark energy ($w_D$) transitioned from $-1$ in the distant past to its current value of $-0.76$, closely resembling the $\Lambda$CDM model in the early epoch and showing significant deviation in the late phase. The evolution of the deceleration parameter in the LDEM signifies its success in explaining the late-time cosmic acceleration. Model selection based on the Bayesian Information Criterion (BIC), incorporating observations from Type Ia Supernovae (SNe Ia), Observational Hubble data (OHD), and Baryon Acoustic Oscillation (BAO) strongly favors the LDEM over the conventional $\Lambda$CDM model, where BIC is estimated to be $\sim -20$. Incorporating the shift parameter derived from the Cosmic Microwave Background (CMB) data shows competing evidence of the LDEM over the standard $\Lambda$CDM. Remarkably, the Hubble constant ($H_0$) value computed using any of the datasets tends to align closely with the predictions from the Cosmic Microwave Background (CMB), suggesting a need to reconsider the local measurement.