(July 22, 2015) A new
theory says dark matter acts remarkably similar to subatomic particles known to
science since the 1930s.
We owe a lot to dark matter – it is the thing keeping
galaxies, stars, our solar system, and our bodies intact. Yet no one has been
able to observe it, and it has often been regarded as a totally new exotic form
of matter, such as a particle moving in extra dimensions of space or its
quantum version, super-symmetry.
Now an international group of researchers has proposed a
theory that dark matter is very similar to pions, which are responsible for
binding atomic nuclei together. Their findings appear in the latest Physical
Review Letters, published on July 10.
“We have seen this kind of particle before. It has the same
properties – same type of mass, the same type of interactions, in the same type
of theory of strong interactions that gave forth the ordinary pions. It is
incredibly exciting that we may finally understand why we came to exist,” says
Hitoshi Murayama, Professor of Physics at the University of California,
Berkeley, and Director of the Kavli Institute for the Physics and Mathematics
of the Universe at the University of Tokyo.
The new theory predicts dark matter is likely to interact
with itself within galaxies or clusters of galaxies, possibly modifying the
predicted mass distributions. “It can resolve outstanding discrepancies between
data and computer simulations,” says Eric Kuflik, a postdoctoral researcher at
Cornell University. University of California, Berkeley postdoctoral researcher
Yonit Hochberg adds, “The key differences in these properties between this new
class of dark matter theories and previous ideas have profound implications on
how dark matter can be discovered in upcoming experimental searches.”