Cardiff Uni scientists progress in solving one of the Universe's biggest mysteries
A new use of technology and a change in theory has led to some promising results
Last updated 16th Dec 2021
Scientists from Cardiff University's Gravity Exploration Institute have led a team that's taken some big steps in uncovering one of the biggest mysteries of the Universe.
In a study published in Nature yesterday (15 December), the group said they've been using incredibly sensitive technology, previously used in landmark discoveries, to search for dark matter.
Thought to make up around 85% of all matter in the Universe, dark matter has never been directly observed and remains an unsolved phenomenon in modern physics, but new research shows we're getting closer.
Despite it never being detected, scientists believe it exists due to its gravitational effect on the Universe - for example, a large amount of unseen matter may explain why galaxies rotate, and how they might've been formed in the first place.
The new study suggests that gravitational-wave equipment, known as laser interferometers, will help scientists finally discover dark matter and even find out what it is made of.
The extremely sensitive detectors were used to discover gravitational waves, in what was one of the biggest scientific breakthroughs of the century.
A change in theory
It was thought that dark matter was made of heavy elementary particles, but since there has been no evidence to suggest such, a new theory says that dark matter is actually a 'scalar field'.
A 'scalar field' consists of invisible waves bouncing around galaxies, including our own Milky Way.
“We realised our instruments could be used to hunt for this new kind of dark matter, although they were initially designed for detecting gravitational waves,’’ said Professor Hartmut Grote, from Cardiff University’s Gravity Exploration Institute, who instigated the investigation.
From 2009-2017, Professor Grote was lead scientist at the UK/German GEO600 Detector, a highly sensitive interferometer which helped develop much of the technology used to detect gravitational waves.
For the first time, the GEO600 was also used in this study to specifically detect dark matter.
“Scalar field dark matter waves would pass right through the Earth and our instruments, but as they do so, would cause objects such as mirrors to vibrate ever so slightly,’’ said lead investigator Sander Vermeulen, also from Cardiff University’s Gravity Exploration Institute.
“Vibrations of mirrors would disturb the beams of light in instruments like GEO600 or the LIGO detectors in a particular way characteristic of dark matter, which is something we should be able to detect, depending on the exact properties of that dark matter.”
Though the team did not directly detect dark matter in the new study, they say they are making important first strides and have already narrowed down findings for future studies.
“We have definitively ruled out some theories that say dark matter has certain properties, so future searches now have a better idea of what to look for,” said Vermeulen.
“We believe these new techniques have the true potential to discover dark matter at some point in the future.”