New Theory Of Dark Matter Zeroes In On Unique Subatomic Particles
June 10, 2013 by UPI - United Press International, Inc.
NASHVILLE (UPI) — Two U.S. physicists say their simple theory may explain dark matter, the mysterious invisible form of matter that makes up 85 percent of the universe.
Vanderbilt University researchers Robert Scherrer and Chiu Man Ho propose that dark matter may be made out of a type of basic particle called the Majorana fermion, a sub-atomic particle whose existence was predicted in the 1930s but which has stubbornly resisted detection.
Scherrer and Ho say their calculations suggest these particles are uniquely suited to possess a rare, doughnut-shaped type of electromagnetic field called an anapole, giving them different properties from particles that possess the more common fields possessing two poles — north and south, positive and negative — and possible explaining why they are so difficult to detect.
“Most models for dark matter assume that it interacts through exotic forces that we do not encounter in everyday life,” Scherrer said. “Anapole dark matter makes use of ordinary electromagnetism that you learned about in school — the same force that makes magnets stick to your refrigerator or makes a balloon rubbed on your hair stick to the ceiling.”
Particles with familiar electrical and magnetic dipoles interact with electromagnetic fields even when they are stationary, Scherrer and Ho said, whereas particles with anapole fields don’t.
They must be moving before they interact, they said, and because dark matter is moving so much more slowly now than it did in the early universe — and because the anapole interaction depends on how fast it moves — these particles would have escaped detection so far.
Their theory can be tested, they said, and the existence of anapole dark matter should either be discovered or ruled out by results from current dark matter detectors buried underground all over the world.
“There are a great many different theories about the nature of dark matter,” Scherrer said. “What I like about this theory is its simplicity, uniqueness and the fact that it can be tested.”