Significance of H0 differences between Type Ia supernovae and other far-field indicators

Determine whether the observed difference in the Hubble constant H0 inferred from Type Ia supernovae (calibrated with Cepheids or Tip of the Red Giant Branch) versus other far-field distance indicators (including the Tully–Fisher relation, the Fundamental Plane relation, Type II supernovae, near-infrared Type Ia supernovae, and surface-brightness fluctuations) is statistically significant, by rigorously comparing the respective H0 estimates derived using a common Cepheid/TRGB calibration framework.

Background

The paper compiles multiple determinations of the Hubble constant H0 that use consistent Cepheid/TRGB calibrations while varying the final distance-redshift relation method (e.g., Tully–Fisher, Fundamental Plane, SNe II, SNe Ia in the near infrared, and surface brightness fluctuations). This comparison shows that H0 values inferred from Type Ia supernovae tend to be on the lower end (approximately 72–74 km/s/Mpc), while other methods generally yield higher values (approximately 73–77 km/s/Mpc).

After revising zeropoint calibrations to ensure consistency across methods, the authors note that the Tully–Fisher relation yields an H0 roughly 3 km/s/Mpc higher than the value inferred from Type Ia supernovae. However, they explicitly state that it is unclear whether this difference is statistically significant and call attention to its implications for the Hubble tension.

References

It is unclear if the difference in $H_0$ between SN Ia and other far-field indicators is significant, although interesting in the context of the Hubble tension that replacement of SNIa with any method makes the tension greater.

— Calibrating the Tully-Fisher Relation to Measure the Hubble Constant  (2412.08449 - Scolnic et al., 2024) in Section 3, Compiling H0 Measurements with Different Distance-Redshift Relations