Hamiltonian Commutator: Finding [H,P_x] for Polarization Operator

In summary, the Hamiltonian commutator is a mathematical operation used in quantum mechanics to calculate the difference between two operators. It is significant in determining the uncertainty in measuring two observables simultaneously and is related to the Heisenberg uncertainty principle. It can also be used to calculate the time evolution of a quantum system and has applications in classical mechanics, statistical mechanics, and electromagnetism.
  • #1
v_pino
169
0

Homework Statement



How do I obtain [H,P_x]? P_x is the polarization operator.


Homework Equations



[tex] H=-\frac{\hbar^2}{2m}\frac{\partial^2 }{\partial x^2}+V(x) [/tex]

[tex] P_x=2Re[c_+^*c_-] [/tex]


The Attempt at a Solution



I know how to commute H and x. But somehow can't think of a way to do the same for H and P_x.
 
Physics news on Phys.org
  • #2
write P_x instead of x; then do the commutation just as you do for x
 

FAQ: Hamiltonian Commutator: Finding [H,P_x] for Polarization Operator

What is a Hamiltonian commutator?

A Hamiltonian commutator is a mathematical operation that calculates the difference between two operators, typically used in quantum mechanics. It is denoted by [A,B] and is equal to the product of A and B minus the product of B and A.

What is the significance of the Hamiltonian commutator in quantum mechanics?

The Hamiltonian commutator is significant in quantum mechanics because it helps determine the uncertainty in measuring two observables simultaneously. If the commutator is zero, the two observables can be measured simultaneously with no uncertainty, but if it is non-zero, there is uncertainty in the measurement.

How is the Hamiltonian commutator related to the Heisenberg uncertainty principle?

The Heisenberg uncertainty principle states that the more precisely we know the position of a particle, the less precisely we can know its momentum, and vice versa. The Hamiltonian commutator is related to this principle because it helps calculate the uncertainty in measuring two observables simultaneously.

Can the Hamiltonian commutator be used to calculate the time evolution of a quantum system?

Yes, the Hamiltonian commutator can be used to calculate the time evolution of a quantum system. This is because the commutator is related to the Hamiltonian operator, which represents the total energy of the system, and the time evolution of a quantum system is determined by its energy.

Are there any applications of the Hamiltonian commutator outside of quantum mechanics?

Yes, the Hamiltonian commutator has applications in classical mechanics as well. It can be used to determine the equations of motion for a system and to calculate the total energy of a system. It is also used in other fields such as statistical mechanics and electromagnetism.

Similar threads

Replies
3
Views
2K
Replies
3
Views
1K
Replies
10
Views
1K
Replies
14
Views
2K
Replies
8
Views
4K
Back
Top