Hubble Tension: The Evidence of New Physics

Understand

The $\Lambda$CDM model provides a good fit to most astronomical observations but harbors large areas of phenomenology and ignorance.

• With the improvements in the precision and number of observations, discrepancies between key cosmological parameters of this model have emerged.
• Among them, the most notable tension is the 4$\sigma$ to 6$\sigma$ deviation between the Hubble constant ($H_{0}$) estimations measured by the local distance ladder and the cosmic microwave background (CMB) measurement.
• In this review, we revisit the $H_{0}$ tension based on the latest research and sort out evidence from solutions to this tension that might imply new physics beyond the $\Lambda$CDM model.