Yonsei University researchers challenge Nobel laureates' cosmic expansion theory

A research team led by Professor Lee Young-wook at Yonsei University has identified two major analytical errors in a rebuttal paper published by researchers from the University of Southampton. The Southampton study, which included Nobel laureates Adam Riess and Brian Schmidt, had argued that the universe continues to undergo accelerated expansion, contradicting Yonsei University's previous findings.

Yonsei University's research suggests that the expansion of the universe has actually entered a deceleration phase and that dark energy may weaken over time. The dispute centers on the analysis of Type Ia supernovae. The Yonsei team argues that the Southampton researchers used an overly broad redshift range to measure the relationship between supernova luminosity and age, which systematically flattened the observed age-bias slope.

Additionally, the Yonsei team pointed out that the Southampton study failed to properly account for how changes in age-bias correction values affect cosmological conclusions. These findings, which challenge the prevailing theory of constant dark energy, have been published in the Monthly Notices of the Royal Astronomical Society (MNRAS).