Pauli Exclusion Principle and Entanglement

Click For Summary

Discussion Overview

The discussion revolves around the relationship between the Pauli Exclusion Principle (PEP) and quantum entanglement, particularly how fermions interact and "know" not to occupy the same space. Participants explore the implications of these concepts in quantum mechanics and their interpretations.

Discussion Character

  • Debate/contested, Conceptual clarification, Exploratory

Main Points Raised

  • One participant questions how fermions avoid occupying the same space and suggests that entanglement might explain their "awareness" of each other.
  • Another participant argues that the PEP is relevant only when the wavepackets of fermions overlap, indicating that they do not "feel" the PEP unless their wavefunctions interact.
  • A third participant seeks clarification on whether entanglement is used to explain the spatial awareness of particles.
  • A later reply notes that while the wave function of indistinguishable particles resembles that of entangled particles, entanglement measurements cannot be performed on indistinguishable particles.

Areas of Agreement / Disagreement

Participants express differing views on the role of entanglement in the context of the PEP and the nature of fermionic interactions. The discussion remains unresolved regarding the relationship between these concepts.

Contextual Notes

There are limitations in the definitions and assumptions regarding the concepts of "awareness" and "empty space" as well as the conditions under which the PEP applies. The discussion also touches on the distinction between distinguishable and indistinguishable particles in quantum mechanics.

g.lemaitre
Messages
267
Reaction score
2
How do fermions, which have vast amounts of empty space, know not to occupy the same space as another fermion? Do physicists say that the two fermions become entangled and that is what enables them to be "aware" of the "existence" of the other fermion? Is entanglement used as an explanation for how objects interact with each other?
 
Physics news on Phys.org
I'm not sure what you mean by "vast amounts of empty space", but in my view, the Pauli exclusion principle doesn't come in until the wavepackets of the fermions in question start to overlap. The PEP is a quantum interference effect anyway and they "feel" it whenever the wavepackets overlap. If they don't overlap, then they don't have the same (spatial) quantum numbers, and they can have the same spin without a problem, i.e. there is no PEP.
 
So entanglement is not used to explain how particles are aware of each others' space?
 
The wave function of a number of indistinguishable particles looks like the wave function of entangled particles. But you cannot perform entanglement measurements on them even in principle. In order to do this, you have to have distinguishable particles (like in EPR experiments, where the particles usually move in different directions).

See also Arnold Neumeier's FAQ: http://arnold-neumaier.at/physfaq/topics/indistEntangled.html
 

Similar threads

Undergrad Two hydrogen atoms and Pauli's exclusion principle
  • · Replies 17 ·
Replies
17
Views
4K
Undergrad Pauli exclusion principle and Hermitian operators
  • · Replies 15 ·
Replies
15
Views
2K
Undergrad How does the Pauli exclusion principle work?
  • · Replies 2 ·
Replies
2
Views
2K
High School Bypassing Pauli Exclusion principle.
  • · Replies 3 ·
Replies
3
Views
1K
Graduate How can a 'Principle' produce a 'Force'?
  • · Replies 12 ·
Replies
12
Views
2K
Graduate Virtual Fermions and Pauli Principle
  • · Replies 2 ·
Replies
2
Views
2K
High School Collision of identical fermions
  • · Replies 18 ·
Replies
18
Views
2K
Undergrad Pauli exclusion principle explained
  • · Replies 2 ·
Replies
2
Views
2K
Graduate Entanglement and the Pauli exclusion principle
  • · Replies 2 ·
Replies
2
Views
2K
Graduate Pauli's exclusion principle and quantum entanglement
  • · Replies 3 ·
Replies
3
Views
3K