Skip to main content

Researchers want to use gravitational waves to learn about dark matter

When two sufficiently massive objects collide — such as when two black holes merge — the forces can actually bend space-time, creating ripples called gravitational waves. These gravitational waves can be detected even from millions of light-years away, making them a way to learn about distant, dramatic events in far-off parts of the universe. And now, a team of astronomers has come up with a method for using gravitational waves to study the mysterious phenomenon of dark matter.

The idea of the research was to create different computer models of what gravitational waves from black hole mergers would look like in universes with different types of dark matter. By comparing the models to what is seen in the real world, we can learn more about what type of dark matter is most likely.

Artist's conception shows two merging black holes similar to those detected by LIGO.
Artist’s conception shows two merging black holes similar to those detected by LIGO. The black holes are spinning in a non-aligned fashion, which means they have different orientations relative to the overall orbital motion of the pair. LIGO found hints that at least one black hole in the system called GW170104 was non-aligned with its orbital motion before it merged with its partner. LIGO/Caltech/MIT

Scientists know that dark matter doesn’t interact with light, but some people think that it could interact with a type of particle called a neutrino. That means that neutrino collisions could prevent dark matter from forming into the structures which are the basis for galaxies, so these particles could stop galaxies from forming. If we could find these “missing” galaxies, that would support the idea that dark matter can be affected by neutrinos.

Recommended Videos

It’s hard to see a galaxy that didn’t form, though. That’s why the researchers suggest using gravitational waves created in black hole mergers as a measure instead. With fewer galaxies there are fewer mergers, and therefore fewer gravitational waves.

Please enable Javascript to view this content

Simulations show that this could be an effective method for learning about dark matter. Current gravitational wave detectors aren’t powerful enough to detect these small effects, but the next generation of instruments could be used for this purpose.

“Dark matter remains one of the enduring mysteries in our understanding of the universe,” said one of the researchers, Sownak Bose of Durham University, in a statement. “This means it is especially important to continue identifying new ways to explore models of dark matter, combining both existing and new probes to test model predictions to the fullest. Gravitational wave astronomy offers a pathway to better understand not just dark matter, but the formation and evolution of galaxies more generally.”

The research was presented at the 2023 National Astronomy Meeting on 5 July.

Georgina Torbet
Georgina has been the space writer at Digital Trends space writer for six years, covering human space exploration, planetary…
Astronomers want your help to spot hidden black holes
This simulation of a supermassive black hole shows how it distorts the starry background and captures light, producing a black hole silhouettes.

Black holes are some of the most mind-bending objects in the universe. They are so dense that anything which passes their event horizon, even light, can't escape. That's where they get their name, as the black hole itself is impossible to see. Fortunately for researchers, many black holes have material like dust and gas around them, and when this material falls into a black hole it can give off bursts of X-rays which allow them to locate the black hole.

But this isn't the case for every black hole. Some are not taking in material, meaning they don't give off X-rays and are much harder to locate. Now, a citizen science project is inviting members of the public to help search for these "hidden" black holes.

Read more
Research confirms enormous mass of supermassive black hole at center of galaxy
Illustration of the black hole Sagittarius A* at the center of the Milky Way.

A new study reveals the most precise information yet about the mass of the enormous black hole at the center of our galaxy. Like most galaxies, the Milky Way has a supermassive black hole at its heart, and the recent research shows more about the mass of this monster called Sagittarius A*or Sgr A* for short.

Illustration of the black hole Sagittarius A* at the center of the Milky Way. International Gemini Observatory/NOIRLab/NSF/AURA/J. da Silva/(Spaceengine) Acknowledgement: M. Zamani (NSF's NOIRLab)

Read more
Small, sneaky black hole discovered outside our galaxy using new method
This artist’s impression shows a compact black hole 11 times as massive as the Sun and the five-solar-mass star orbiting it. The two objects are located in NGC 1850, a cluster of thousands of stars roughly 160 000 light-years away in the Large Magellanic Cloud, a Milky Way neighbour. The distortion of the star’s shape is due to the strong gravitational force exerted by the black hole.

A new detection method has been used to discover a small black hole outside the Milky Way, which could pave the way for the discovery of more hidden small black holes within our galaxy as well.

Very large black holes are relatively easy to detect because they give off X-rays as the matter is heated to glowing hot as it is pulled toward the black hole's event horizon. By looking for these X-rays, or for the gravitational waves given off by black hole collisions, astronomers can spot big black holes. But it's more difficult to spot smaller black holes which are comparable in mass to our sun because most of them don't give off either X-rays or gravitational waves.

Read more