Pauli exclusion principle
A fundamental rule in subatomic physics which states that no two electrons, or other types of fermion (governed by Fermi-Dirac statistics), can occupy the same quantum state at the same place and time; it was formulated by the Austrian-born physicist Wolfgang Pauli in 1925. In a system of fermions, the lack of empty neighboring states often prevents most particles from contributing to the system properties, which thus depend only on the states borderly the filled ones – the so-called Fermi surface.
The exclusion principle prevents white dwarfs that are below the Chandrasekhar limit from collapsing: the electrons are squashed together to form electron degenerate matter, which resists any further attempts at compression (see degenerate electron pessure).
Related category PARTICLE PHYSICS
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