Dark Matter Theory Answers Key Questions Regarding the Mysterious Substance

Dark matter may possess a rare, doughnut-shaped electromagnetic field called an analope, according to researchers at the University of Vanderbilt.

In the study, published in the journal Physics Letters B, physicists Robert Scherrer and post-doctoral fellow Chiu Man Ho demonstrate through detailed calculations that the elusive substance may be made out of a type of basic particle called the Majorana fermion.

The existence of fermions, which are particles like the electron and quark, was first predicted in 1929, and while the neutrino remains the primary candidate for the theoretical particle, scientists have never been able to prove that this is the case.

Similarly, the existence of dark matter was also first proposed in the 1930s in an effort to explain the discrepancies in the rotational rate of galactic clusters.

Since then, scientists have come to essentially rule out the possibility that dark matter particles carry electrical charges. And while several physicists have examined dark matter particles that don’t carry electrical charges but feature electric or magnetic dipoles, these models have been ruled out for Majorana particles, leading Ho and Scherrer to take a closer look at dark matter with an anapole magnetic structure.

If they are right, then dark matter contains properties that differ from those of particles that possess the more common fields made up of two poles (north and south, positive and negative, etc.). This in turn would explain why dark matter particles are nearly impossible to detect.

“There are a great many different theories about the nature of dark matter,” Scherrer said in a press release. “What I like about this theory is its simplicity, uniqueness and the fact that it can be tested.”

Scherrer further explained that while most models assume that dark matter interacts through exotic forces, anapole dark matter, should it exist, would make use of the same kind of ordinary electromagnetism a person encounters when sticking a magnet to a fridge or rubbing a balloon on his or her hair and watching it stick to the ceiling.

Supporting their theory is the fact that particles with anapole fields, unlike those with more familiar electrical and magnetic dipoles, have to be moving before they interact with electromagnetic fields - the faster they move, the stronger the interaction.

This suggests that anapole particles would have been much more interactive during the early years of the universe right after the Big Bang, and less so as time went on and space expanded and cooled. Such a lack of movement would then mean those particles today are largely quiet, and undetectable, but only just barely.