Galaxy cluster measurements support Newton and Einstein gravity on cosmic scales
Updated
Updated · ScienceAlert · May 9
Galaxy cluster measurements support Newton and Einstein gravity on cosmic scales
9 articles · Updated · ScienceAlert · May 9
Patricio Gallardo's team analysed velocities from 686,000 galaxies in clusters 5 to 7 billion light-years away, using the kinematic Sunyaev-Zeldovich effect.
They found gravity weakens with distance as standard theory predicts, rather than staying stronger at vast ranges as some modified-gravity models would require.
The result strengthens dark matter as the leading explanation for unexplained cosmic motions, though researchers say the nature of that unseen matter remains unknown.
With modified gravity theories on the ropes, could exotic 'excited dark matter' or primordial black holes finally solve the puzzle?
If gravity isn't broken, why have decades of searching failed to find the 85% of matter that is supposedly 'dark'?
ACT’s 2026 Results: Gravity’s $1/r^2$ Law Validated on Largest Cosmic Scales, Bolstering Dark Matter Theory
Overview
In May 2026, groundbreaking studies using the Atacama Cosmology Telescope (ACT) confirmed that gravity behaves just as Newton and Einstein described, even across the vast distances between galaxy clusters. This means gravity weakens with the square of the distance, a principle first explained for our solar system but now proven on much larger scales. By observing how galaxy clusters move toward each other, scientists found that our current understanding of gravity holds true throughout the universe. This powerful confirmation supports the standard model of cosmology and strengthens the case for dark matter.