Does Linear momentum operator and angular momentum operator

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SUMMARY

The discussion centers on the commutation relations between the linear momentum operator \( P_x \) and the angular momentum operator \( L_x \). It is established that \( [P_x, L_x] \) does not commute, as \( L_x \) is defined in terms of the position \( \vec{r} \) and momentum \( \hat{\vec{p}} \) operators. The user highlights the importance of understanding the derivatives involved, specifically how derivatives with respect to different variables yield zero when not aligned. The commutation relations for momentum operators, specifically \( [P_x, P_y] = [P_x, P_z] = 0 \), are also confirmed.

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hellomister
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Homework Statement


Does Px Lx operators commute?

Homework Equations


This is just me wondering


The Attempt at a Solution


I tried doing this and I got something weird, my friend said that when you take a derviative with respect z or something that when you try to take the derivative of something that's not with respect to z it goes to 0. Is this true? p.s. I am not very good at math.
 
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You tell me. L_x is made up of rs and ps. Which r and ps is L_x made of, and which r and ps does p_x commute with?
 
[tex]\hat{\vec{L}} = \vec{r} \times \hat{\vec{p}}[/tex]

[tex]\times[/tex] is the cross product...

Do the math and then see if they commute

ps
[px , py] = [px , pz] = 0
 

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