Physics:Quantum Commutator: Difference between revisions

From ScholarlyWiki
Jump to navigation Jump to search
Repair Quantum page See also and references
Remove leading BOM from Quantum page
Line 1: Line 1:
{{Short description|Operator expression measuring non-commutativity}}
{{Short description|Operator expression measuring non-commutativity}}
{{Quantum book backlink|Foundations}}
{{Quantum book backlink|Foundations}}
{{Quantum article nav|previous=Physics:Quantum Matrix mechanics|previous label=Matrix mechanics|next=Physics:Quantum Measurement problem|next label=Measurement problem}}
{{Quantum article nav|previous=Physics:Quantum Matrix mechanics|previous label=Matrix mechanics|next=Physics:Quantum Measurement problem|next label=Measurement problem}}

Revision as of 21:55, 23 May 2026

← Previous : Matrix mechanics
Next : Measurement problem →

In quantum mechanics, a commutator measures how much two operators fail to commute. For two operators A and B, the commutator is

[A,B]=ABBA.

A commutator compares doing two quantum operations in different orders.

Role in quantum mechanics

Commutators are central because quantum observables are represented by operators. If two observables have a nonzero commutator, the corresponding quantities generally cannot both have sharply defined values in the same state.

The canonical position and momentum commutator is

[x,p]=iI.

This relation underlies the uncertainty principle and is one of the basic structures of matrix mechanics.

See also

References


Author: Harold Foppele