Updated

Updated · The Brighter Side of News · Jul 13

MIT-Led Physicists Flag GW190728 as Dark Matter Candidate in 1 of 28 Merger Events

Updated

Updated · The Brighter Side of News · Jul 13

MIT-Led Physicists Flag GW190728 as Dark Matter Candidate in 1 of 28 Merger Events

Q: Physicists found one potential signal. How many more cosmic collisions must they observe to finally prove dark matter exists?

No one can yet say how many more black-hole mergers are needed. One suggestive event is far from enough, and the new study does not set a fixed numerical threshold for “proof.” The reason is statistical. The standout event, GW190728, favored the dark-matter-cloud explanation with a Bayes factor of about 3.5. That counts as modest or moderate evidence, not a discovery. In practical terms, it means the signal is interesting enough to follow up, but weak enough that it could still be a fluctuation, a modeling issue, or an astrophysical effect unrelated to dark matter. What would change that is repetition. Researchers say they would need another similar signal, and likely several, showing the same kind of distortion in gravitational waves and pointing to a consistent ultralight particle mass. Independent reanalysis by other groups would also be essential. A single event can hint; a pattern across multiple events can persuade. How many events that means depends on their quality. A few very clean, high-signal detections could be more convincing than dozens of marginal ones. Future observatories such as the Einstein Telescope, Cosmic Explorer, and LISA should greatly improve sensitivity, making it easier to tell whether these phase shifts really come from scalar dark matter clouds around black holes. So the honest answer is: more than one, probably several, but there is no agreed magic number yet. The field now has a new method, not a final proof.

2 articles · Updated · The Brighter Side of News · Jul 13

GW190728, a black hole merger detected in 2019, was the only one of 28 cataloged events to show a statistical preference for a dark-matter-like scalar cloud rather than vacuum.
MIT-led researchers built and validated a waveform model that searches gravitational-wave phase shifts caused when merging black holes move through dense clouds of ultralight scalar particles.
The preferred particle mass was about 10^-12 electron volts, and the signal's support was modest — a Bayes factor of roughly 3.5 in natural log units — leaving the result far short of a dark matter detection.
Alternative explanations including orbital eccentricity, line-of-sight acceleration and deviations from general relativity did not gain support, while standard vacuum models risk slightly biasing inferred merger properties.
Future LIGO-Virgo-KAGRA runs and next-generation detectors such as Einstein Telescope and Cosmic Explorer could turn this method into a new way to probe dark matter around black holes.

Sources

The Brighter Side of News2d ago

MIT-Led Physicists Detect Potential Dark Matter Traces in Gravitational Wave Event GW190728

MIT News2d ago

A new way to spot signs of dark matter | MIT News | Massachusetts Institute of Technology

Was a gravitational wave distortion a hint of dark matter, or a crack in our understanding of black holes?

Physicists found one potential signal. How many more cosmic collisions must they observe to finally prove dark matter exists?

If dark matter forms invisible clouds around black holes, what other cosmic structures are hiding in plain sight?

GW190728 Anomaly: Gravitational Wave Data Offers First Tentative Evidence of Dark Matter Around Black Holes

Overview

A groundbreaking new method has emerged in the search for dark matter, pioneered by physicists like Soumen Roy and Rodrigo Vicente. This approach uses data from LVK detectors to look for signs of dark matter around black holes. The gravitational wave event GW190728, detected in 2019, stands out as an intriguing early candidate that could carry an imprint of dark matter. By analyzing gravitational wave signals from black hole mergers, researchers hope to uncover new physics and open a fresh frontier in understanding the universe’s most mysterious substance.

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