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fermion
subject			fact

fermion	has quantum behavior Fermi-Dirac statistics
	has spin half-integral
	obeys exclusion principle
	has definition Any particle with half-integer spin: 1/2 h bar, 3/2 h bar, 5/2 h bar, etc. All fermions obey Pauli's exclusion principle.
	has definition An elementary particle whose spin is a half-integral multiple of h/2π. Fermions include the baryons, the leptons and their antiparticles, and obey the Pauli exclusion principle (cf. boson).
	has definition A particle, or pattern of string vibration, with half a whole odd number amount of spin; typically a matter particle.
	has definition Particle with half-integral spin. Fermions obey the exclusion principle, which says that no two fermions can exist in an atom in the same quantum state; in practice this restricts the number of electrons, which are fermions, permitted in each electron shell.
	has definition Elementary particle with fractional spin. The proton, electron, neutron, and other elementary particles are all fermions.
	is a kind of particle
particle	has frequency inversely proportional to the wavelength
	has wavelength inversely proportional to its momentum
	has charge
	has mass
physical object	has location or center of gravity
	has angular momentum
	has velocity
	has momentum
	has temperature
	has volume
	has extent
	has material

Kinds of fermion :

• baryon (10 kinds, 69 facts) - Heavy subatomic particle composed of 3 quarks.
• even-odd nucleus (3 facts) - Nucleus that contain even numbers of protons but odd numbers of neutrons.
• lepton (15 kinds, 84 facts) - A fermion which is not made of quarks., The generic name for any spin-1/2 particle which does not feel the strong nuclear force. The six known leptons are the electron, the muon, the tau lepton, and their respective neutrinos. The name was originally coined to refer to light particles., Any fermion that does not participate in the strong interactions. Leptons include the electron family and the muon family., Elementary particle that does not participate in the strong interactions, including electrons, muons, and neutrinos., Elementary particle that have no measurable size and are not influenced by the strong nuclear force. Electrons, muons, and neutrinos are leptons., A class of non-strongly-interacting particles that includes the electron, muon, tau, and their associated neutrinos. See Table 7.1 on page 120., A fundamental particle of nature, which may interact via all of the fundamental forces except the strong nuclear force. The electron is an example of a lepton., Elementary particle like the electron and neutrino that do not experience the strong nuclear force. Unlike the strongly interacting hadrons, the leptons have small masses.
• quark (9 kinds, 37 facts) - The hypothetical constituent of the elementary particles that interacts via glue forces. Originally only three quarks were hypothesized; today it appears that six are required. For a variety of theoretical reasons, free quarks can never be seen., Fundamental particle of which protons, neutrons and electrons are now thought perhaps to be made up. There are possibly three or four types of quark. It is even possible that quarks themselves may be made up of still more fundamental particles., A sub-atomic particle which is a fundamental building block of the hadrons., A fermion with fractional electric charge., A particle that is acted upon by the strong force. Quarks exist in six varieties: up, down, charm, strange, top, bottom and three "colors" (red, green, blue)., One of the fundamental, indestructible particles of nature, out of which many other subatomic particles are made. Five types of quarks have been discovered, and it is believed that a sixth also exists. Quarks interact mainly via the strong nuclear force and the electromagnetic force., Fundamental particles from which all hadrons are made. According to the theory of quantum chromodynamics, protons, neutrons, and their higher-energy cousins are composed of trios of quarks, while the mesons are each made of one quark and one antiquark. Held together by the strong nuclear force, quarks are not found in isolation in nature today; see asymptotic freedom.

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