Scientists have developed a new method to search for dark matter using gravitational waves from black hole collisions. While dark matter does not emit light, it may leave subtle imprints when black holes merge within dense clouds of it. Researchers from MIT and European institutions modeled how such signals would differ from mergers in empty space and tested their predictions against data from 28 black hole merger events detected by LIGO-Virgo-KAGRA. Most signals matched vacuum expectations, but one event, GW190728, showed a preference for the dark matter model. This does not confirm detection, but it opens a new observational pathway.

The study focuses on light scalar particles, a theoretical form of dark matter that could gain density near rapidly spinning black holes through a process called superradiance. At high densities, such matter might alter gravitational waveforms in detectable ways. The team’s simulations predicted these deviations and compared them to real data, finding a tentative match in GW190728. The signal originated from a binary black hole system about 20 times the mass of the Sun.

Researchers caution that the statistical significance is too low to claim discovery. However, the work demonstrates that without proper models, dark matter signatures could be misclassified as vacuum mergers. Future data from upgraded detectors may provide stronger evidence. The approach allows scientists to probe dark matter at much smaller scales than previously possible.