New Kind of Dark Matter Could Form ‘Dark Atoms’
The mysterious dark matter that makes up most of the matter in the universe could be composed, in part, of invisible and nearly intangible counterparts of atoms, protons and electrons, researchers say.
Dark matter is an invisible substance thought to make up five-sixths of all matter in the universe. Scientists inferred the existence of dark matter via its gravitational effects on the movements of stars and galaxies.
Most researchers think dark matter is composed of a new type of particle, one that interacts very weakly at best with all the known forces of the universe save gravity. As such, dark matter can almost never be seen or touched, and rarely even collides with itself.
This might not hold true for all forms of dark matter, though. Now, some researchers suggest a new kind of dark matter could exist, representing about one-fifth of all dark matter in the universe, making it potentially as plentiful as conventional matter.
"There is no good reason to assume that all the dark matter in the universe is built out of one type of particle," study author Andrey Katz of Harvard University told SPACE.com.
These new dark matter particles would essentially consist of heavy “dark protons” and light “dark electrons.” They would interact with each other far more than other dark matter particles to form “dark atoms” that use “dark photons” to interact through a sort of “dark electromagnetism,” much as regular protons and electrons interact through photons in conventional electromagnetism to build the atoms making up the stuff of everyday life. If dark atoms are possible, they could react with each other for dark chemistry, much as regular atoms interact chemically.