Recent scientific studies suggest that dark matter, which weighs much more than ordinary matter, may not exist. Instead, physicist Naman Kumar suggests that gravity, which keeps planets in orbit and prevents galaxies from blowing apart, may actually weaken at different distances. Newton’s constant moves with distance in his equation, which comes out as 1/r, with the result that dark matter is not needed to explain galaxy rotation curves.

A new gravitational model allows Newton’s gravitational constant to change with scale, according to new research, while building on quantum field theory, according to study author Naman Kumar. In this “infrared running” model, the pull of gravity decreases more slowly: at very large distances, it follows the 1/r rule rather than 1/r².

This naturally produces the flat rotation curves seen in spiral galaxies without any additional matter. Kumar applied the model to real galactic data and found that it reproduced the rotations observed using only visible matter.

As Kumar explains, “These results suggest that the infrared running scenario can cause galaxy rotation without involving dark matter”. Implications and Outlook The results of Kumar’s research were published in the journal Physics Letters B in 2025.

He wants to point out that any changes in gravity must be subtle to match the results observed in the early universe. Their model is slowly evolving while maintaining consistency with the results of the cosmological background as it dissociates at a late stage.

The next line of research is comparing the results observed with gravitational lensing as well as in clusters of galaxies. Although the research “does not yet fully replace dark matter,” Kumar believes this method “highlights the potentially hidden complexity of gravity. “.