Spin 1/2

Elementary particles with a spin of 1/2

In quantum mechanics, spin is an intrinsic property of all elementary particles. All known fermions, the particles that constitute ordinary matter, have a spin of ⁠1/2⁠. The spin number describes how many symmetrical facets a particle has in one full rotation; a spin of ⁠1/2⁠ means that the particle must be rotated by two full turns (through 720°) before it has the same configuration as when it started.

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