2/26/2026 Jenny Applequist for The Grainger College of Engineering
Yunes and collaborators calculated what the passage of dark matter clumps through the Earth should look like in data gathered by gravitational wave detectors and compared their results against so-far unexplained transient signals observed by detectors. They determined the movement of dark matter is not likely the cause of the observed phenomena.
Written by Jenny Applequist for The Grainger College of Engineering
Scientists have been able to detect the presence of gravitational waves since 2015, when the first instruments capable of doing so were set up. However, these instruments capture many other signals as well. Sometimes these signals’ sources are easy to identify—perhaps there was a small earthquake, or an airplane passed overhead—but some of the collected data have remained mysterious.
Recent work co-led by Nicolas Yunes has dealt a heavy blow to one interesting hypothesis: that clumps of dark matter passing through Earth are responsible for some of the enigmatic “glitches” found in the data.
The team examined data collected by gravitational wave detectors located in Louisiana and Washington state.
Yunes, a professor of physics who specializes in general relativity and gravitation, explained that whenever two massive objects—say, two black holes or two neutron stars—collide, that event will produce vibrations in gravity that travel, at the speed of light, in all directions away from the source. “They eventually hit Earth, and when they hit Earth, they produce a signal in these ‘LIGO’ instruments,” he said.
However, the extremely sensitive instruments are also continually detecting many other things in addition to gravitational waves. Thanks to the wide geographical distribution of the two detectors, though, much of that noise can easily be identified as having some local source.
“The probability that a plane is going to be going over the instrument in Louisiana at the same precise time as another plane with similar features is going over the instrument in Washington state, this is essentially zero. So you compare the data streams and then you expect that if it’s a real gravitational wave that goes through Earth, then you’re going to detect the same pattern in both detectors at roughly the same time,” Yunes explained. “That’s called ‘coincidence,’ and it’s a very important statistical test for the reality of signals.”
But even after the non-coincident noise is removed from consideration, the data still contain many kinds of coincident “glitches” that resemble short, bursty gravitational waves, but whose causes are unknown.
What Yunas and his co-authors asked was, “Could it be that some of these glitches are being produced by ‘little’ balls of dark matter, less than two kilometers across, that are going through the detector?”
Dark matter is thought to be far more common than ordinary matter, but is invisible; it is known to exist only because of its observable gravitational effects. If a small clump of dark matter came hurtling through space towards the Earth, it wouldn’t slam violently into the surface like an asteroid; it would pass harmlessly through our planet, unnoticed by humans. In theory, though, it might be detected by gravitational wave detectors.
“So we asked the question, if something like that were to happen, what would be the signal that the detectors would record? And we solved some equations and… came up with an answer, and the answer is, it looks a lot like some of the glitches that LIGO detects all the time!”
The team then analyzed the glitches that have already been recorded.
“Our conclusion, after a very detailed statistical analysis, was that in all likelihood, these glitches were not caused by these balls of dark matter,” Yunes said. Of the 84 glitches studied in detail, the team was able to conclude that 75 were certainly not caused by dark matter. For the remaining nine, the team couldn’t rule out a dark matter origin—but if dark matter was responsible, it would have needed to have remarkably low density, ten million times less dense than water.
“In this way, we could place the first direct upper limit on the local density of clumpy dark matter with gravitational wave data,” Yunes said.
He reflected that anytime you turn a machine on and it starts “listening to the universe,” the collected data will unavoidably include a lot of noise. “But ‘noise’ can also be rich in what it’s telling us about the universe. So what we might think of as noise, like glitches, might actually be data. And it’s worth considering whether those things we thought of as something to discard, because they are not ‘real’ signals, well, could they be teaching us something new about the universe? I think that’s an interesting possibility.”
A paper describing the work, “Dark matter clumps as sources of gravitational-wave glitches in LIGO-Virgo-KAGRA data,” has been published in the American Physical Society’s journal Physical Review D. Yunes’s co-authors include Prof. Ezequiel Alvarez of the Universidad de San Martín, Argentina; Federico Ravanedo, a Ph.D. student co-advised by Alvarez and Yunes; and Scott Perkins, who earned a Ph.D. under Yunes and is now at the Lawrence Livermore National Laboratory.