Speaker
Description
The debate about the value of present Hubble parameter H0 has heated up in recent years with more precise measurements of different techniques. The standard candle measurements at low redshift (e.g., supernovae) yield an H0 value of 74.0+-1.5 km/s/Mpc, while the standard ruler measurements at high redshift (e.g., cosmic microwave background) give an H0 of 67.5+-0.5 km/s/Mpc. The tension is beyond 4.4σ.
In this talk, I will introduce the new development of the H0 problem from both high redshift and low redshift observations. Especially, our findings are consistent with reported discrepancies in the cosmic dipole and anisotropies in galaxy cluster scaling relations. The reported variations in H0 across the sky suggest that Hubble tension may be a symptom of a deeper cosmological malaise.
