Particle.news
Download on the App Store
16 ARTICLES
·
last wk.

New Study Claims the Universe Is Now Decelerating After Supernova Age-Bias Correction

The peer-reviewed analysis attributes past acceleration signals to a progenitor-age bias in Type Ia supernovae, yielding distances consistent with BAO and CMB indications of weakening dark energy.

The Milky Way's Galactic Centre
Credit: NASA Goddard
Image
Supernova explosion in the center of the galaxy "Elements of this image furnished by NASA" (Credit: muratart on Shutterstock)

Overview

  • Yonsei University researchers report a strong correlation between Type Ia supernova brightness and progenitor age based on about 300 host galaxies, with significance reported at 99.999% and a 5.5σ level.
  • Applying the age correction removes support for the standard ΛCDM model and aligns supernova distances with BAO and CMB results, pointing to time-varying, weakening dark energy and a present-day decelerating expansion.
  • The authors note that DESI’s earlier conclusion of current acceleration combined BAO with uncorrected supernovae, whereas the corrected sample indicates deceleration today and matches BAO-only or BAO+CMB inferences.
  • The findings, published in Monthly Notices of the Royal Astronomical Society, challenge the supernova evidence that underpinned the 2011 Nobel Prize but have been met with skepticism over age measurements and methodology.
  • The team is conducting an ‘evolution-free’ test using age-controlled supernova samples, and expects Vera C. Rubin Observatory discoveries of more than 20,000 host galaxies to provide decisive checks within the next few years.