There’s a new way to track dark matter

Scientists from Australia have presented a new way to track dark matter. The researchers note that their method is ten times more accurate than analogs.

A small team of astronomers has presented a new way to “see” the dark matter that surrounds galaxies. The researchers note that the new technique is ten times more accurate than any analogs. Details of the work can be found in the Monthly Notices of the Royal Astronomical Society.

Scientists estimate that up to 85% of the mass in the universe is invisible. Dark matter cannot be seen directly, because it does not interact with light in the same way as ordinary matter that makes up stars, planets and other celestial bodies. However, the researchers noted that it can be measured – through the influence of gravity, which produces dark matter.

Paul Gurry, a PhD student at Swinburne University of Technology who led the research, explains, “It’s like looking at a flag trying to figure out how hard the wind is blowing. You can’t see the wind, but the movement of the flag can tell you how hard it blows. ”

The new study builds on an effect called weak gravitational lensing, a feature of Einstein’s theory of general relativity. “Dark matter will very slightly distort the image of everything behind it,” said researcher Edward Taylor, who also took part in the research. “This effect is very similar to reading a newspaper through glass or some other obstruction.”

Weak gravitational lensing is already one of the most successful ways to map dark matter in the universe. Now the research team has used the ANU telescope in Australia to map areas of matter that are not involved in electromagnetic interaction. “Since we know how stars and gas should move inside galaxies, we know roughly what this galaxy should look like,” the researchers note. “By measuring how distorted the real images of galaxies are, we can figure out how much dark matter is needed to explain this phenomenon.”