Sarkar Team Reanalyzes 1,700 Supernovae, Challenges Dark Energy as Expansion May Be Slowing
Updated
Updated · ScienceDaily · Sep 9
Sarkar Team Reanalyzes 1,700 Supernovae, Challenges Dark Energy as Expansion May Be Slowing
1 articles · Updated · ScienceDaily · Sep 9
Summary
More than 1,700 Pantheon+ Type Ia supernovae, reanalyzed with a correction for progenitor star age, no longer favored uniform cosmic acceleration and instead pointed to possible deceleration.
The study also found the apparent acceleration was strongest along the direction of local motion seen in the cosmic microwave background and faded with distance, a pattern the authors say dark energy should not produce.
A separate paper in the same Monthly Notices issue reached the opposite conclusion, with Maria Vincenzi and co-authors arguing supernova evidence still supports an accelerating universe.
Hundreds of thousands of supernovae expected from Rubin Observatory's LSST are now positioned as the next major test of whether expansion is accelerating, directional, or slowing.
How will the Rubin Observatory's massive new dataset finally resolve the fierce debate over our slowing universe?
Could the Nobel-winning discovery of dark energy be merely an illusion caused by aging stars?
If the universe isn't uniformly accelerating, what mysterious force aligns cosmic expansion with Earth's movement?
Is the Universe Really Accelerating? The 2026 Pantheon+ Supernova Controversy and the Dark Energy Crisis
Overview
In 2026, researchers led by Subir Sarkar challenged the idea of cosmic acceleration by correcting supernova data for the age of their progenitor stars. This correction revealed that the universe may actually be decelerating, not accelerating. The analysis also uncovered a strong directional effect, suggesting that what looks like acceleration is an optical illusion caused by our local motion through space, rather than true dark energy. These findings question the reliability of treating supernovae as uniform 'standard candles' and highlight the need for new, high-precision data from projects like the Rubin Observatory's LSST to resolve the debate about the universe's expansion.