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An elementary fermion is a particle with a half-integer spin which can not be further decomposed into smaller particles. There are 96 elementary fermions, sorted into three generations which each have similar properties to the previous but with a greater mass.

Due to the spontaneous symmetry breaking by the Higgs field, normal elementary fermions are typically found in their left-handed forms and antimatter elementary fermions are typically found in their right-handed forms.

Quarks

Quarks come in two categories: up-type quarks and down-type quarks. The up-type quarks include the up quark, the charm quark, and the top quark. The down-type quarks include the down quark, the strange quark, and the bottom quark.

The left-handed up-type quarks have an electric charge of +23 and a weak isopin of +½, and the left-handed down-type quarks have an electric charge of -13 and a weak isospin of -½. The right-handed up-type quarks have an electric charge of +23, and the right-handed down-type quarks have an electric charge of -23, with both having a weak isospin of 0.

Each quark can come in six different colours (red, green, blue, antired, antigreen and antiblue), with normal quarks coming in the normal colours and antiquarks coming in the anticolours. These colours dictate how the quark interacts by the strong nuclear force. Because of how the strong force behaves over long distances, quarks can not be isolated, and must come bound in colourless hadrons.

Leptons

Leptons also come in two categories: electron-type leptons (the "down" leptons) and neutrino-type leptons (the "up" leptons). The electron-type leptons include the electron, the muon, and the tauon. The neutrino-type leptons include the electron neutrino, the muon neutrino, and the tauon neutrino.

The left-handed electron-type leptons each have an electric charge of -1, and a weak isospin of -½. The left-handed neutrino-type leptons each have no electric charge, and a weak isospin of +½. The right-handed electron-type leptons have an electric charge of -1, and the right-handed neutrino-type leptons have no electric charge, with both having a weak isospin of 0.

Leptons come in two "colours" (white and black), with normal leptons being white and antileptons being black, both of which are colourless and do not interact with the strong force, so they can be isolated and need not exist in bound states.

Because right-handed neutrinos have no colour, charge or weak isospin, they do not interact by any of the fundamental forces except for gravity.

Summary Table

Left-Handed Fermion Charge Isospin Colour Right-Handed Fermion Charge Isospin Colour
u, c, t +23 +12 r, g, b uR, cR, tR +23 0 r, g, b
d, s, b -13 -12 r, g, b dR, sR, bR -23 0 r, g, b
νe, νμ, ντ 0 +12 rgb νR 0 0 rgb
e, μ, τ -1 -12 rgb eR, μR, τR -1 0 rgb
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