Study Shows Dark Matter Obeys Gravity, Helps Settle Old Debate

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Extreme Tech
Study Shows Dark Matter Obeys Gravity, Helps Settle Old Debate
Graham Templeton
Thu, November 6, 2025 at 11:45 AM EST
2 min read



The movements of galaxies could reveal the physics behind dark matter. (Credit: NASA)


A new study in the journal Nature examines the distribution of dark matter in the universe, attempting to figure out if it obeys the same laws as regular matter. What it found suggests that dark matter does obey gravity, helping to lock down the possibility that it obeys some other, more mysterious force.

It's a slightly outdated way of thinking about it, but there are classically four "fundamental forces" in the universe: electromagnetism, the strong nuclear force, the weak nuclear force, and gravity. For a long time, however, astrophysicists have been discovering elements of the universe that are difficult to understand using only these four explanatory tools.

This has led to a small but persistent belief that these elements could be subject to a fifth, more esoteric force only able to be seen in such exceptional aspects of the cosmos. One such element is dark matter. The universal-scale distribution of dark matter has been the subject of significant study, and this paper pushes that line of inquiry further than ever.

Researchers in Switzerland and Spain looked at the movement of galaxies relative to the gravitational fields they should be experiencing. These observations were compared against predictions for how the visible matter in these galaxies should move if the dark matter that makes up the majority of their matter was being affected the same way.



dark matter distribution render
Renders of the distribution of dark matter show an almost creepy web of universe-spanning threads. Credit: NASA


They found that the dark matter did not seem to be disturbing the movements of the visible matter in the galaxies, which moved as expected if dark matter was subject to gravity. A fifth force would cause the dark matter to move differently, and its gravitational interactions with the visible matter would drag it off its expected course.

Actually, the team did put some limits on the findings. Nastassia Grimm, first author of the study, told Space.com that "at this stage...these conclusions do not yet rule out the presence of an unknown force. But if such a fifth force exists, it cannot exceed 7% of the strength of gravity—otherwise it would already have appeared in our analyses."

This tends to be the way that science addresses counterfactuals. It's easier to prove that something does exist than that it doesn't, so a total refutation of the fifth force will probably involve iteratively shaving down the range of its possible effect to the point that, even if it did exist, it wouldn't much matter.

In that spirit, the researchers think that upcoming data from the separate experiments could produce data fine enough to detect a force as weak as 2% of gravity.

https://www.yahoo.com/news/articles/study-shows-dark-matter-obeys-164537633.html