Скачать или смотреть CosmoVerse seminar: Taylor Hoyt: Systematics in Distance Ladder H0

Taylor Hoyt

Systematics in Distance Ladder H0: How large of a role can they still play in the Hubble Tension?

The Hubble Tension is often quoted at more than 5 sigma significance, suggesting definitive evidence for new physics. In this talk, however, I present evidence that suggests uncertainties have been underestimated in the Cepheid-supernova (SN) analysis that strongly influences the Hubble Tension landscape. I then discuss a recent James Webb Space Telescope (JWST) program which undertook a partially blinded, multi-method check on the Hubble Telescope (HST) distance measurements underlying previous distance ladder H0 estimates. The new JWST results yielded a lower H0 (70.4 ± 1.9 km/s/Mpc) than the latest SH0ES estimate (73.17 ± 0.86 km/s/Mpc), despite sharing the same geometric zero point calibration and SNe. Resolving this inconsistency in local distance ladder measurements is paramount before a realistic assessment of the Hubble Tension can be made.
To that end, I introduce a new, blinded analysis of the SNe used to determine H0 within the Union3+UNITY SN cosmology framework. Preliminary findings have revealed discrepancies with (and within) Pantheon+, including a systematic offset in their host masses that both biases their H0 and suppresses their evidence for evolving dark energy. We also see significant disagreements over the colors of SNe when estimated from identical data. Once unblinded, we will report separate H0 values based on either the SH0ES-Cepheid or CCHP-TRGB distances.

Register to listen live to our next seminar: https://cosmoversetensions.eu/for-sci...

Visit our website: https://cosmoversetensions.eu
Like our socials:
Twitter:   / cacosmoverse  
Linked-in:   / cacosmoverse  
Facebook:   / cacosmoverse