University of Melbourne researchers have proposed a new theory to pin down the origin of dark matter, describing it in a new study. Their paper aims to help scientists in Australia and abroad deepen the search for dark matter.
"Our proposed mechanism suggests that the dark matter abundance may have been determined in a cosmological phase transition," said Dr. Michael Baker, one of the study's authors and a Postdoctoral Research Fellow at the University of Melbourne.
The study explains that phase transitions in the early universe are supposed to take place and can be compared to gas bubbles forming in boiling water. The research team has shown that dark matter particles are naturally expected to find it very difficult to penetrate these bubbles, providing a clear understanding of the amount of dark matter detected in the universe.
Although several studies have looked for the particle, dark matter, none have been successful yet. Many researchers have mainly looked for Weakly Interacting Massive Particles, which has been the preferred candidate for dark matter for decades. These studies, though, have not shown anything yet, which really inspires theorists to look beyond the box.
"We know dark matter is out there, but we don't know much else," said Dr. Baker, then pointing out that there's a good chance it can be easily detected in a laboratory if it's a new particle. Its properties could then be determined, like its interactions and mass. In turn, we would learn something new and significant about the cosmos.
Scientific reviews performed in conjunction with Assistant Professor Andrew Long of the Rice University, Texas, and Professor Joachim Kopp from CERN and the University of Mainz encourages for new scientific methods for dark matter hunting.
One exciting feature of the theory, according to Professor Kopp, is that it operates with dark matter particles that are much heavier than any other candidates, such as the famous Weakly Interacting Massive Particles that have been the subject of many scientific searches in the past. The work of the team motivates the expansion of the search for dark matter to heavier masses.
For the future of scientific dark matter searches in Australia, the results may be particularly significant.
The first underground particle physics facility in the Southern Hemisphere will be the Stawell Underground Physics Laboratory, which is currently under construction in regional Victoria, one kilometer below the ground in a disused gold mine, which will host several dark matter search experiments in the years to come.
New scientific ideas can help accelerate studies that will test the largest variety of candidates for dark matter, giving scientists the best chance of unearthing the dark matter mystery.
The work has been published in Physical Review Letters.
