Pauli exclusion principle

American  

noun

Physics.

1. exclusion principle.

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Pauli exclusion principle British  

noun

1. Sometimes shortened to: exclusion principle.  physics the principle that two identical fermions cannot occupy the same quantum state in a body such as an atom

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Pauli exclusion principle Scientific  

/ pô′lē,pou′- /

1. The principle that two fermions of a given type, such as electrons, protons, or neutrons, cannot occupy the same quantum state. It does not apply to bosons. This principle plays a key role in the electron orbital structure of atoms, since it prevents more than two electrons from occupying any given orbital (two are allowed, since they may have opposite spin, and thus be in different quantum states).

2. See also orbital degeneracy pressure

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Etymology

Origin of Pauli exclusion principle

First recorded in 1925–30; named after W. Pauli

Example Sentences

Fermions must obey the Pauli exclusion principle, which means two fermions cannot share the same quantum state.

From Scientific American • Apr. 4, 2022

Fermions obey the Pauli exclusion principle: no two fermions can ever occupy the same exact quantum state.

From Nature • Jul. 2, 2020

The Pauli exclusion principle can be formulated as follows: No two electrons in the same atom can have exactly the same set of all the four quantum numbers.

From Textbooks • Feb. 14, 2019

This statement is known as the Pauli exclusion principle, because it excludes electrons from being in the same state.

From Textbooks • Aug. 12, 2015

In 1933, the Indian physicist Subrahmanyan Chandrasekhar realized that the Pauli exclusion principle had only a limited ability to fight against the squeeze of gravity.

From "Zero: The Biography of a Dangerous Idea" by Charles Seife