A new study by the University of Sussex for the first time modeled dark matter in a new way, disrupting conventional thinking about the universe. The study, published yesterday, October 2, 2019, in Physical Examination Letters was conducted in conjunction with Princeton, Harvard, Cambridge, and MIT universities and others.
Scientists have long suspected that much of the universe is made up of invisible particles or dark matter, and they must be very cold and heavy. But finding evidence is elusive, prompting researchers to consider alternative theories.
New simulations show how stars and galaxies could form and cluster together into the origin of the universe, if dark matter in the mass is very light and not too heavy, as most scientists have suggested.
A physicist from the University of Sussex worked with an international team to calculate how dark matter would behave and what early galaxies would look like if it were "fuzzy" and extremely light in mass.  The "fuzzy" theory of dark matter is that dark matter is made up of tiny particles so light that they act as quantum matter and are moved by waves. Their quantum nature is seen on a galactic scale. Usually, dark matter was considered cold (ie, where the particles do not move). But there is doubt over this theory, since particle accelerators have not yet been able to create such dark matter. The new fuzzy dark matter theory has gained popularity as it makes sense in particle physics, but it has never been fully simulated
The simulations show the forms of galaxies that would be made at the beginning of the universe if dark matter were fuzzy and extremely light. The team confronts them with familiar galaxies formed in cold dark matter scenarios. As the universe ages, the galaxies have changed shape. But when new generation telescopes are launched – including the James Webb Space Telescope, which Sussex physicists are working on – scientists expect to be able to look further into the history of the universe to see what it looked like before.  Dr. Anastasia Fialkov, who did research at the University of Sussex, said:
"The nature of dark matter is still a mystery. Fuzzy dark matter theory makes sense in terms of fundamental physics, such as string theory, and is therefore an interesting candidate for dark matter. And if the theory of fuzzy dark matter is proven to the right new generations of powerful telescopes, then we have nailed the nature of dark matter: one of the greatest mysteries of all.
"Worldwide, researchers are looking for dark matter, and particle physics are building There are models for dark matter, and many assume that dark matter is “cold.” The fuzzy theory of dark matter, where dark matter acts like a wave on a galactic scale, now presents a plausible alternative scenario: that dark matter is tiny, moving by waves, acting "as quantum matter. Our simulations are the first to create galaxies in the context of fuzzy dark matter."
Professor Katie Romer, an astrophysicist at the School of Mathematical and Physical Sciences at the University of Sussex, said:
"Hunting for Dark Matter is a bit like 'Where's Wally?'" the clues we need to look for are equivalent to striptease and walley's hat, but we still haven't found it.We may not have been looking for walley (cold dark matter) all this time, but we should have been looking for wendy (fuzzy dark matter). new research is as important as it is is another clue to the search equivalent to Wendy's striped socks. "
Philip Moch, an Einstein employee at Princeton, says:
" Dark matter is a cradle in which galaxies are born, and cradle shapes also form galaxies. Dark Matter models have different cradle shapes, especially in the young Universe, which is a great place to look for new clues about what dark matter is. "
What do studies show?
Researchers have found that if dark matter is cold, then galaxies in the early universe would be formed in almost spherical" halos. "But if dark matter was fuzzy, the early universe would have looked different, galaxies would have formed at first.
The Cold Dark Matter Hypothesis helps to describe the large-scale structure of the observable Universe well, and so most modeling galaxies are based on assumptions. and that dark matter is cold, but there are differences between observations and predictions of cold dark matter. If you look at very small galaxies, dark matter distribution does not fit the predictions of theoretical models. Moreover, because particle accelerators have not yet detected dark matter, the model is cold.
The team developed the first realistic predictions of what early galaxies might look like in a fuzzy dark matter universe. The goal is to create a map for future telescopes, such as the James Webb Space Telescope, which may be able to look far enough back in time to spot ancient galaxies. If they see galaxies with tails or "filaments" as imitated in this study, it may begin to confirm that the dark matter is fuzzy by nature.
Dr. Fialkov transferred to the University of Cambridge.
Reference: Philip Moch, Anastasia Fialkov, Mark Fogelsberger, Fernando Besserra, Mustafa A. Amin, Sovnak Bose, Michael Boylan-Colchin, P & A; Robles and Jesus Zavala, October 2, 2019, Physical Examination Letters .
doi: 10.1103 / PhysRevLett.123.141301