Cosmic acceleration may be biased

A new MNRAS analysis of >1,700 Type Ia supernovae argues that when you correct for the ages of the stars that produce the explosions, the residuals that were read as universal acceleration shrink or reverse, and the inferred acceleration even appears to vary by direction on the sky. Other teams dispute the result, making this a clear empirical fork that upcoming telescopes (e.g., Vera Rubin, Euclid, Roman) can resolve. — If real, the claim undermines the empirical basis for dark energy and would force revisions to fundamental cosmology, shifts in research priorities, and public narratives about the limits of scientific certainty.