A new study suggests that dark energy may have changed from repulsive to attractive about 9.5 billion years ago.

What it means

Dark energy is typically thought to have a negative pressure that drives cosmic acceleration. This study suggests that its pressure may have flipped from negative (repulsive) to positive (attractive) about 9.5 billion years ago, meaning the universe's expansion would have been decelerating since then. If true, this would fundamentally challenge the standard cosmological model, which assumes dark energy has been repulsive for most of cosmic history.

Accuracy & sourcesGrounded

The claim comes directly from a new peer-reviewed study (the primary source), but it represents a radical, unconfirmed hypothesis that contradicts decades of observational evidence for recent acceleration. The Science Daily article is a press release summary that may simplify the findings; independent verification is needed before the claim can be considered solid.

How new