Browsing: Axions

Axions are hypothetical elementary particles proposed as a solution to the strong CP (charge-parity) problem in quantum chromodynamics (QCD), which is the theory describing the strong nuclear force. The strong CP problem arises from the fact that QCD does not seem to violate CP symmetry, even though the equations allow for it. Axions were first theorized in the late 1970s by physicists Roberto Peccei and Helen Quinn, who introduced a new symmetry to explain this apparent conservation. Beyond addressing the strong CP problem, axions have gained significant attention in cosmology as potential dark matter candidates. Unlike other particles, axions are expected to have a very low mass and interact very weakly with other matter, making them difficult to detect but possibly constituting a significant portion of the universe’s missing mass. Various experimental efforts are underway to detect axions, which, if discovered, could provide deep insights into both particle physics and cosmology.