New York, July 23 (IANS): Dark matter may not be an exotic substance as has been assumed -- a new theory proposes that it acts remarkably similar to subatomic particles known to science since the 1930s.

Dark matter is very similar to pions, which are responsible for binding atomic nuclei together, the study said.

"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," said one of the researchers Hitoshi Murayama, professor of physics at the University of California, Berkeley in the US.

Their findings appeared in the journal Physical Review Letters.

Although dark matter is believed to be the substance keeping galaxies, stars, our solar system, and our bodies intact, 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.

The new theory predicts dark matter to interact with itself within galaxies or clusters of galaxies.

"It can resolve outstanding discrepancies between data and computer simulations," Eric Kuflik, postdoctoral researcher at Cornell University in the US said.