Eigenvectors eigenvalues and constant of motion

AI Thread Summary
The discussion revolves around verifying that the angular momentum operator Lx is a constant of motion for a particle described by a specific Hamiltonian. Participants suggest checking if L and H commute, relating this to the equations of motion via the Heisenberg equation. For the second part, the ground state wavefunction Y0(x,y,z) can be expressed as a product of the individual wavefunctions for each dimension, leading to a form like e-x²/2 + e-y²/2 + e-z²/2. The conversation highlights the importance of separating variables in quantum mechanics to solve for wavefunctions. Overall, the thread emphasizes key concepts in quantum mechanics related to angular momentum and wavefunction representation.
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Homework Statement



a.) The motion of a particle in the 3-dimensional space is described by the Hamiltonian H = Hx+Hy+Hz, where

Hx=1/2*(px2+x2), Hy=1/2*(py2+y2), Hz=1/2*(pz2+z2)

Check that the standard angular momentum operators Lx, is a constant of motion.

b.) By knowing that the ground state wavefunction for Hx is proportional to e-x2/2, write the wavefunction Y0(x,y,z) representing the ground state for H (you are not required to fix the normaliszation of the wavefunctions in this problem).

Homework Equations





The Attempt at a Solution



a.) Do you need to check if L and H commute?
b.) I really don't have a clue any tips?
 
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umagongdi said:

Homework Statement



a.) The motion of a particle in the 3-dimensional space is described by the Hamiltonian H = Hx+Hy+Hz, where

Hx=1/2*(px2+x2), Hy=1/2*(py2+y2), Hz=1/2*(pz2+z2)

Check that the standard angular momentum operators Lx, is a constant of motion.

b.) By knowing that the ground state wavefunction for Hx is proportional to e-x2/2, write the wavefunction Y0(x,y,z) representing the ground state for H (you are not required to fix the normaliszation of the wavefunctions in this problem).

Homework Equations


The Attempt at a Solution



a.) Do you need to check if L and H commute?
b.) I really don't have a clue any tips?
a.) Do you need to check if L and H commute?

Can you relate that commutator to the equations of motions. HINT: Look up the Heisenberg equation of motion.

b.) I really don't have a clue any tips?

Assume the wave function can be separated in its variables.
 
G01 said:
Assume the wave function can be separated in its variables.

Oh i think i get it now thanks. You can just separate the wave function like this?

Y0(x,y,z)=e-x2/2+e-y2/2+e-z2/2
 
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