A 5% measurement of the Hubble constant from Type II supernovae

Abstract

The most stringent local measurement of the Hubble constant from Cepheid-calibrated Type Ia supernovae (SNe Ia) differs from the value inferred via the cosmic microwave background radiation (Planck+ΛCDM) by more than 5𝜎. This so-called "Hubble tension" has been confirmed by other independent methods, and thus does not appear to be a possible consequence of systematic errors. Here, we continue upon our prior work of using Type II supernovae to provide another, largely-independent method to measure the Hubble constant. From 13 SNe II with geometric, Cepheid, or tip of the red giant branch (TRGB) host-galaxy distance measurements, we derive H 0 = 75.4 +3.8 −3.7 km s −1 Mpc −1 (statistical errors only), consistent with the local measurement but in disagreement by ∼ 2.0𝜎 with the Planck+ΛCDM value. Using only Cepheids (𝑁 = 7), we find H 0 = 77.6 +5.2 −4.8 km s −1 Mpc −1 , while using only TRGB (𝑁 = 5), we derive H 0 = 73.1 +5.7 −5.3 km s −1 Mpc −1 . Via 13 variants of our dataset, we derive a systematic uncertainty estimate of 1.5 km s −1 Mpc −1 . The median value derived from these variants differs by just 0.3 km s −1 Mpc −1 from that produced by our fiducial model. Because we only replace SNe Ia with SNe II -and we do not find tension between the Cepheid and TRGB H 0 measurements -our work reveals no indication that SNe Ia or Cepheids could be the sources of the "H 0 tension." We caution, however, that our conclusions rest upon a modest calibrator sample; as this sample grows in the future, our results should be verified.

Perturbed FLRW Metric Explains the Difference in Measurements of the Hubble Constant

“…Determination of the Hubble constant using the cosmic distance ladder [4,5] and gravitational lensing [6,7] yields a difference of about 1/10 of its value. We consider the dependence of the change rate of photon energy on the direction of its motion.…”

Thermal friction as a solution to the Hubble and large-scale structure tensions

“…It has grown to the critical 5σ-level between its two most precise constraints -one based on a ΛCDM fit to the cosmic microwave background (CMB) as observed by Planck [4] and the other from more direct measurements in the late universe using the distanceladder approach by SH0ES [5]. This mismatch is in fact echoed at a lower discrepancy level by several measurements [6,7], with the early universe and a ΛCDM model consistently finding a lower H 0 [4,[8][9][10][11][12] than the late universe [5,[13][14][15][16][17][18][19][20][21][22][23][24][25][26]. A similar but milder tension is emerging in descriptions of the large-scale structure (LSS) of the Universe.…”

Thermal Friction as a Solution to the Hubble and Large-Scale Structure Tensions

“…It has grown to the critical 5σ-level between its two most precise constraints -one based on a ΛCDM fit to the cosmic microwave background (CMB) as observed by Planck [3] and the other from more direct measurements in the late universe using the distanceladder approach by SH0ES [4]. This mismatch is in fact echoed at a lower discrepancy level by several measurements [5,6], with the early universe and a ΛCDM model consistently finding a lower H 0 [3,7] than the late universe [8][9][10][11][12][13][14]. A similar but milder tension is emerging in descriptions of the large-scale structure (LSS) of the Universe.…”