“Most models of dark matter suggest that they interact only through exotic forces that we do not meet in everyday life. Anapole dark matter uses ordinary electromagnetism, which you read about even at school - the same force that allows magnets to attach to a refrigerator or balloons rubbed on their hair against a wall. ”
So said Robert Scherrer , a theoretical physicist at Vanderbilt University.
“In addition, this model gives very specific predictions about the speed with which dark matter should appear in dark matter detectors hidden underground throughout the world. Forecasts show that in the near future the existence of anapole dark matter can be openly or refuted as a result of the experiment. ”
The bulk of matter in the Universe can be made of particles that have an unusual donut-shaped electromagnetic field - anapole. This new theory, which gives dark matter particles a rare form of electromagnetism, has become more popular after a detailed analysis of Scherrer and Ph.D. Chiu Man Ho.
“There are tons of different theories about the nature of dark matter. What I like about this theory is its simplicity, uniqueness and the fact that it can be verified, ”says Scherrer.
In an article called “ Anapolis Dark Matter, ” physicists have suggested that dark matter, an invisible form of matter, representing 85% of all matter in the universe, may consist of particles called Majorana fermions . Their existence was predicted back in the 30s of the last century, but has not been proven since.
Some physicists believe that dark matter consists of Majorana particles, but Scherrer and Ho performed detailed calculations that showed that these particles have a unique donut-shaped electromagnetic field called anapole. The field gives particles properties that differ from those of other particles that have more common double fields (north-south, positive and negative) and explain why particles are so hard to fix.
Fermions - like electrons and quarks - are the building blocks of matter. Their existence was predicted by Paul Dirac in 1928. Ten years later, shortly before the mysterious disappearance into the sea, the Italian physicist Ettore Majorana slightly changed Dirac's formulation, as a result of which he suggested the existence of an electrically neutral fermion. Since then, physicists have long searched for Majorana fermions. The main candidate for this post was neutrinos, but scientists could not determine the basic nature of this elusive particle.
The existence of dark matter was also first proposed in the 30s to explain the discrepancies in the rotation speed of galactic clusters. Astronomers subsequently discovered that the speed at which stars rotate around individual galaxies also does not fit into the predicted model. A detailed observation showed that stars that are further from the center of the galaxy move at a much higher speed than predicted from data on the visible matter of which the galaxies are composed. It became obvious that there is a huge amount of invisible “dark” matter, which would be the easiest way to explain the problem.
Scientists have suggested that dark matter cannot be seen through a telescope, since it does not interact very much with light and other electromagnetic radiation. In fact, astronomical observations were based on the possibility that particles of dark matter do not have an electric charge at all.
More recently, a number of physicists have suggested that dark matter particles do not have an electric charge, but have an electric or magnetic dipole. The only problem is that even these more complex models do not work for Majorana particles. And this is one of the reasons that Ho and Scherrer decided to take a closer look at dark matter with anapole magnetic moment.
“Although Majorana fermions are electrically neutral, the fundamental symmetry of nature prohibits them from acquiring any electromagnetic properties other than anapole,” Ho says.
The existence of a magnetic anapole was predicted by the Soviet physicist Yakov Zeldovich in 1958. Since then, anapoles have been found in the magnetic structure of the nuclei of cesium-133 and ytterbium-174 atoms.
Particles with a conventional electric and magnetic dipole interact with an electromagnetic field even in a stationary state. Particles with anapole - do not interact. They must move for interaction, and the faster - the stronger the interaction. As a result, anapole particles should be much more interactive in the early days of the universe and gradually become less active as the universe expands and cools.
The particles of anapole dark matter proposed by Ho and Scherrer were supposed to annihilate in the early Universe, like the other proposed particles of dark matter, and the remaining particles should make up what we call dark matter today. But since dark matter moves very slowly today, and since the anapole interaction depends on the speed of motion of matter, these particles could well remain beyond the scope of the radar of scientists.
Recall, not so long ago, a certain Eric Weinstein appeared, whose theory also intends to overturn the traditional understanding (or misunderstanding) of the principles of dark matter.
The article is based on materials .
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