Solve Hamiltonian Operator Question: What is [\hat{H}, i\hbar]?

In summary, the conversation discusses a question regarding position and momentum operators, specifically the term [\hat{H}, i\hbar]. It is clarified that when i \hbar is present in an operator equation, it usually represents i \hbar \hat{I}, where \hat{I} is the identity operator. The question involves proving the equality of [H,xp] and [H,px], and it is mentioned that having the identity operator does not affect the outcome. The individual has come to a realization and no further assistance is needed.
  • #1
Jenkz
59
0

Homework Statement


I'm completing a question regarding position and momentum operators, however I'm stuck on one term.

What does [[tex]\hat{H}[/tex], i[tex]\hbar[/tex]] equal? Or what does it mean?

Thanks.
 
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  • #2
If you have [tex]i \hbar [/tex] in an operator equation, it usually means [tex]i \hbar \hat{I}[/tex], where [tex]\hat{I}[/tex] is the identity operator.
 
  • #3
Ok maybe putting it into context might help.

The question needs us to prove that [H,xp] =[H,px]

Where xp =px + [x,p]
 
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  • #4
When we write

[tex]
[\hat{x},\hat{p}] = i \hbar ,
[/tex]

this is an operator equation, so we should really have an operator on the RHS. This operator is the identity operator and it's usually left out because it's clear from the context. To be precise, we'd write

[tex]
[\hat{x},\hat{p}] = i \hbar \hat{I}.
[/tex]
 
  • #5
It doesn't really seem to make a difference in my case if I have the identity operator. Anyhow, I've realized what I need to do, so thanks anyways :)
 

FAQ: Solve Hamiltonian Operator Question: What is [\hat{H}, i\hbar]?

What does [\hat{H}, i\hbar] represent in quantum mechanics?

[\hat{H}, i\hbar] represents the commutator of the Hamiltonian operator and the imaginary unit multiplied by the reduced Planck's constant. It is a fundamental equation in quantum mechanics that helps determine the time evolution of a quantum system.

How is [\hat{H}, i\hbar] related to the uncertainty principle?

The uncertainty principle states that the position and momentum of a particle cannot be simultaneously known with absolute certainty. The commutator [\hat{H}, i\hbar] is related to this principle as it represents the uncertainty between a particle's energy and time. This means that the more precisely we know a particle's energy, the less precisely we know its time, and vice versa.

Why is the commutator [\hat{H}, i\hbar] important in quantum mechanics?

The commutator [\hat{H}, i\hbar] is important in quantum mechanics because it is a key part of the Schrödinger equation, which describes the time evolution of a quantum system. It also helps determine the energy spectrum of a quantum system and plays a role in many other important quantum mechanical principles and equations.

How is [\hat{H}, i\hbar] used in solving quantum mechanical problems?

[\hat{H}, i\hbar] is used in solving quantum mechanical problems by helping to find the eigenvalues and eigenstates of a quantum system. These eigenvalues and eigenstates can then be used to calculate various properties of the system, such as energy levels and transition probabilities.

Are there any alternative formulations of [\hat{H}, i\hbar]?

Yes, there are alternative formulations of [\hat{H}, i\hbar] in different mathematical frameworks, such as the Heisenberg picture and the Dirac formalism. These formulations may present the commutator in a different way, but they all ultimately represent the same fundamental concept in quantum mechanics.

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