##  [Pauli Exclusion Principle](/index.php/pauli-exclusion-principle) 

  ##  [Pauli Exclusion Principle](https://natural.quantumdictionary.io/pauli-exclusion-principle-0) 

  

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**Natural & Formal Sciences Dictionary**

 







 

 

 

 



 

 

 

 

Definition

In this dictionary, the Pauli exclusion principle is the quantum rule that no two identical fermions in the same quantum system may occupy exactly the same single-particle quantum state simultaneously; it is expressed by the antisymmetry of the fermionic wavefunction and by occupation-number constraints in second-quantized descriptions.

 

 

 

 

 





 

 



 ##  [Pauli Exclusion Principle](https://physics.quantumdictionary.io/pauli-exclusion-principle-1) 

  

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- Natural & Formal Sciences -

**Physics Dictionary**

 







 

 

 

 



 

 

 

 

Definition

The quantum rule that no two identical fermions can occupy the same complete set of single‑particle quantum numbers within a single quantum system; equivalently, the antisymmetry of the fermionic many‑body wavefunction under exchange enforces occupation numbers of single‑particle states to be at most one. It is a consequence of particle exchange symmetry for half‑integer spin particles.