Probing Cosmic Background Dynamics with a Cosmological-model-independent Method

Understand

The Hubble constant $H_0$ tension has emerged as the most serious crisis in modern cosmology, potentially indicating that the $\Lambda$CDM model may not describe our universe accurately.

• In this paper, we establish a new, cosmological-model-independent method to study the cosmic background dynamics.
• Using the latest Pantheon+ Type Ia supernova (SN Ia) sample and the model-independent SN Ia sample (P+1690), we derive values for the luminosity distance, the Hubble parameter, and the deceleration parameter at five different redshift points ranging from 0.12 to 0.52.
• Our analysis shows that results obtained from the Pantheon+ sample align with the predictions of the $\Lambda$CDM model within 2$\sigma$ confidence level (CL), while those obtained from the P+1690 sample exhibit deviations of about $2\sim3\sigma$ CL.