CERN Begins Search for Elusive 'Dark Photon'
Physicists at the European Organization for Nuclear Research (CERN) start the hunt for the 'dark photon,' a particle they hope will bridge the gap between dark matter and visible matter. If they manage to find it, this could drastically change our current conception of physics.
CERN Control Room [Image Courtesy of Wikimedia]
Some physicists theorize that 85 percent of our Universe consists of dark matter. This largely stems from there being more gravity holding us together than can be accounted for by visible matter. Just as photons carry electromagnetic forces, the dark photon could carry the force of dark matter.
"To use a metaphor, an otherwise impossible dialogue between two people not speaking the same language (visible and dark matter) can be enabled by a mediator (the dark photon), who understands one language and speaks the other one," explained Sergei Gninenko, spokesperson for the NA64 collaboration.
The NA64 experiment wants to find signatures of this interactions through observing the conservation of energy. They will aim an electron beam (whose energy the team precisely knows) at a detector. Interactions between electrons and nuclei in the detector produce photons. The energy measured should be equivalent to that of the electrons. If dark photons really exist, they'll elude the detector, taking away a substantial portion of the electron energy.
CERN researchers are attempting to make real the hypothetical, just as they did when detecting the Higgs boson. Finding any sort of signature serves as the first step toward figuring out dark matter. Unlocking the mysteries of dark matter then unlocks the mysteries of the universe itself. Should this succeed, we could even have to rethink our concept of gravity and other governing forces.
The NA64 team hasn't announced when they expect the experiments to yield results, but we'll certainly know when they do.
To get a quick primer on exactly what dark matter is (and is not), check out this video below:
With many scientists still unhappy with the IAU's definition of "planet," it's possible the debate will never be resolved!