New Waveform Model Finds Dark-Matter Candidate

Physicists at MIT and European partners built a waveform model that predicts the shape of a binary-black-hole merger occurring inside a dense dark-matter cloud. Applying it to the 28 clearest LIGO-Virgo-KAGRA signals from the first three observing runs, they identified one event, GW190728, whose pattern aligns better with the dark-matter prediction than with the vacuum expectation.

A new way to spot signs of dark matter

Dark matter is inferred only via gravity. Light-scalar particles, far lighter than an electron, can form coherent waves. Superradiance around a rapidly spinning black hole transfers rotational energy to these waves, amplifying their density. The resulting cloud can imprint a characteristic distortion on the emitted gravitational wave, which the new model quantifies.

A new way to spot signs of dark matterGravitational Waves Could Become New Tool in Hunt for Dark Matter

The analysis was led by postdoctoral researcher Josu Aurrekoetxea (MIT) and involved Soumen Roy (Université Catholique de Louvain, Royal Observatory of Belgium), Rodrigo Vicente (University of Amsterdam), Katy Clough (Queen Mary University of London), and Pedro Ferreira (University of Oxford). The work used public LVK data and received partial support from the U.S. National Science Foundation and MIT’s Center for Theoretical Physics.

A new way to spot signs of dark matter

The team examined the 28 highest-signal-to-noise LVK events. Twenty-seven matched vacuum predictions; GW190728, detected on 28 July 2019 and inferred to involve a ~20 M? binary, showed a better fit to the dark-matter waveform, suggesting a possible imprint.

A new way to spot signs of dark matter

Aurrekoetxea said the method provides a way to screen gravitational-wave data for dark-matter signatures but stresses that the statistical preference for GW190728 is modest and not a detection. He calls for independent verification. Roy noted the technique’s promise as LVK gathers more data, while Vicente highlighted that black-hole observations could probe dark-matter regimes beyond other methods.

A new way to spot signs of dark matter

• “We know that dark matter is around us. It just has to be dense enough for us to see its effects,” — Josu Aurrekoetxea, MIT

A new way to spot signs of dark matter

• “The statistical significance of this is not high enough to claim a detection of dark matter, and further checks should be performed by independent groups,” — Josu Aurrekoetxea, MIT

A new way to spot signs of dark matter

• “We now have the potential to discover dark matter around black holes as the LVK detectors keep collecting data in the coming years,” — Soumen Roy, Université Catholique de Louvain

A new way to spot signs of dark matter

• “Using black holes to look for dark matter would be fantastic,” — Rodrigo Vicente, University of Amsterdam

A new way to spot signs of dark matter

The LVK network plans higher-sensitivity observing runs, expanding the catalog of high-quality mergers. Researchers will refine the dark-matter waveform model and apply it to new data, aiming to confirm or reject the GW190728 hint and to uncover additional candidates.

A new way to spot signs of dark matter