Which Operators Commute in Quantum Mechanics?

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In summary, the conversation discusses finding subsets of commuting operators for a free particle moving in one dimension. The goal is to find sets of operators in which the commutator of every operator in the set commutes with every other operator in the set.
  • #1
Dassinia
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Hello

Homework Statement



For a free particle moving in one dimension, divide the following set of operators into subsets of commuting operators:
[P,x, H, p]

Homework Equations





The Attempt at a Solution


I don't get the statement itself
What does the set represents for the particle ?
Dividing into subsets is like finding the operators that commute in the set ?

Thanks
 
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  • #2
You're just supposed to find the subsets of that set such that the commutator of every operator in a subset commutes with every other operator in that subset.


So if we had[itex]A, B,[/itex] and [itex]C[/itex], and [itex][A,B] = 0[/itex], but [itex][A,C] \neq 0[/itex] and [itex][B,C] \neq 0[/itex], then your sets would be

[itex]\left\{ A, B \right\}, \left\{ C\right\}[/itex]
 
  • #3
Thank you !
 

FAQ: Which Operators Commute in Quantum Mechanics?

What are commutating operators in quantum mechanics?

Commutating operators are operators in quantum mechanics that commute with each other, meaning that their order of operation does not affect the end result of the calculation. This is a fundamental concept in quantum mechanics and is related to the uncertainty principle.

What is the significance of commutating operators in quantum mechanics?

The significance of commutating operators lies in the fact that they represent observables that can be measured simultaneously with precision. This is because their commutator, which measures the non-commutativity of two operators, is equal to zero.

Can commutating operators be used to predict the outcome of quantum measurements?

No, commutating operators cannot be used to predict the exact outcome of quantum measurements. They can only provide information about the range of possible outcomes and the probability of those outcomes occurring.

How do commutating operators relate to the Heisenberg uncertainty principle?

The Heisenberg uncertainty principle states that it is impossible to know both the position and momentum of a particle with absolute precision. Commutating operators are related to this principle because operators that do not commute, such as position and momentum operators, cannot be known simultaneously with absolute precision.

Are all operators in quantum mechanics commutating?

No, not all operators in quantum mechanics are commutating. The commutativity of operators depends on the specific physical system being studied. In some cases, operators may commute with each other, while in others they may not.

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