Mastodawn

The Atacama Cosmology Telescope - A Test of the #GravitationalForce Law on Cosmological Scales Using the Kinematic Sunyaev-Zeldovich Effect: https://arxiv.org/abs/2604.14327 -> Gravity follows Newton and Einstein’s rules, even at cosmic scales: https://penntoday.upenn.edu/news/gravity-follows-newton-and-einsteins-rules-even-cosmic-scales - by tracking galaxy clusters hundreds of millions of lightyears apart, Penn physicist Patricio Gallardo and collaborators find that the laws of gravity written by Newton and Einstein still hold, leaving little doubt that invisible dark matter exists.

The Atacama Cosmology Telescope: A Test of the Gravitational Force Law on Cosmological Scales Using the Kinematic Sunyaev-Zeldovich Effect

The mean pairwise velocity of massive halos reflects the gravitational force law on cosmic scales. We combine cosmic microwave background intensity maps from the Atacama Cosmology Telescope and a galaxy catalog from the Sloan Digital Sky Survey to estimate the mean pairwise velocity using the kinematic Sunyaev-Zeldovich (kSZ) effect. On scales from 30 -- 230 megaparsecs, we constrain the gravitational acceleration between pairs of halos at separation $r$ to be $g\propto 1/r^n$ with $n=2.1\pm 0.3$, which is consistent with Newtonian gravity in an expanding spacetime (\textit{i.e.}, the standard $Λ$CDM model). This constraint shows agreement with an inverse quadratic radial dependence over the large distances separating galaxy halos, as expected in standard cosmology. Upcoming surveys have the potential to rule out $n = 1$ at $10σ$ significance. Our results establish the kSZ effect as a powerful tool for testing gravity on cosmological scales.

arXiv.org