- #1
Brewer
- 212
- 0
This is a little bit of a weird one.
The question asks me to prove that [tex][\hat{L}^2,\hat{L}_z ][/tex] is equal to zero. I know what to do with it and how commutators work, and I know that L2 = Lx2 + Ly2 + Lz2 (where the 2 means squared) and I have expressions for Lx2, Ly2 and Lz2, but I was just wondering if there's a nice compact way of writing L2 out, as the version I'll get after adding the 3 expressions is really long and is a ridiculous amount of (albeit simple) working out, in which I'm likely to make sign errors (which I did on the previous question).
If I have to go this long winded way so be it (and I will do - just like to have something to aim at), but if it could be simplfied then I'm sure it'd be a slightly easier question.
Thanks guys
Brewer
The question asks me to prove that [tex][\hat{L}^2,\hat{L}_z ][/tex] is equal to zero. I know what to do with it and how commutators work, and I know that L2 = Lx2 + Ly2 + Lz2 (where the 2 means squared) and I have expressions for Lx2, Ly2 and Lz2, but I was just wondering if there's a nice compact way of writing L2 out, as the version I'll get after adding the 3 expressions is really long and is a ridiculous amount of (albeit simple) working out, in which I'm likely to make sign errors (which I did on the previous question).
If I have to go this long winded way so be it (and I will do - just like to have something to aim at), but if it could be simplfied then I'm sure it'd be a slightly easier question.
Thanks guys
Brewer