Definition of FERMION

fermion

Plural: fermions

Noun

  • any particle that obeys Fermi-Dirac statistics and is subject to the Pauli exclusion principle
  • Any elementary or composite particle that has half-integer spin and thus obeys Fermi–Dirac statistics and the Pauli exclusion principle (equivalently, a particle for which the wavefunction of any system of identical such particles changes sign whenever two are swapped); a baryon, a lepton or a quark;
  • Any elementary or composite particle that has half-integer spin and thus obeys Fermi–Dirac statistics and the Pauli exclusion principle (equivalently, a particle for which the wavefunction of any system of identical such particles changes sign whenever two are swapped); a baryon, a lepton or a quark; (slightly more loosely) any such particle or any composite particle composed of fermions.
  • any such particle or any composite particle composed of fermions.

Examples

  • "According to the spin–statistics theorem, the wavefunction of a system of identical fermions (particles of half-integer spin) is antisymmetric under the operation of swapping any two particles."
  • "The fermions treated by the Standard Model are the (composite) baryons and the (elementary) leptons and quarks."

Origin / Etymology

From Fermi + -on. Named after Italian-American physicist Enrico Fermi. Coined by English physicist Paul Dirac in 1945 in a lecture titled "Developments in Atomic Theory".

Synonyms

fermion

Scrabble Score: 12

fermion is a valid Scrabble (US) TWL word
fermion is a valid Scrabble Word in Merriam-Webster MW Dictionary
fermion is a valid Scrabble Word in International Collins CSW Dictionary

Words With Friends Score: 14

fermion is a valid Words With Friends word