Overview
- The peer‑reviewed study from Yonsei University, published in Monthly Notices of the Royal Astronomical Society, reanalyzes Type Ia supernova distances.
- Direct host‑galaxy age measurements reveal a 5.5‑sigma correlation between standardized brightness and progenitor age, dubbed the Progenitor Age Bias.
- After correcting for this bias, the supernova data disagree with the ΛCDM constant‑dark‑energy model at more than 9 sigma and indicate present‑day deceleration.
- The corrected results align with Dark Energy Spectroscopic Instrument measurements that exclude supernovae and may help ease the Hubble‑constant discrepancy.
- The authors, including Junhyuk Son and Young‑Wook Lee, call the finding provisional and point to upcoming Rubin Observatory surveys of ~20,000 supernovae for decisive tests.