What are the equations for angular momentum?

AdrianMay · Mar 2, 2011

Hi folks,

The attachment is from Sakurai where he's getting started on angular momentum. I don't understand how he gets between the two equations I stuck a ? on. Any hints gratefully appreciated.

Adrian.

tiny-tim · Mar 2, 2011

Hi Adrian!

It's ordinary algebra …

A(pq + rs)B = ApqB + ArsB,

together with S_z|+> = |+>, S_z|-> = -|->, and the expansion definition of exp

dextercioby · Mar 2, 2011

I swear the exact same question was on this forum or the HW:Advanced Physics 2 weeks ago.

What are the equations for angular momentum?

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What are the equations for angular momentum?

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