Ok, so for some reason this section of the GRE book makes 0 sense to me ... maybe because i haven't taken the class yet, maybe i'm missing something ...(adsbygoogle = window.adsbygoogle || []).push({});

It says "If you have a spin-1 particle with m = +1 and a spin-1/2 particle with m = +1/2, then m_tot = +3/2 (this part makes sense, you just add them), and the system must be in the state with s_tot = 3/2"

why is s_tot just 3/2? I thought the possible spin states of the system are s1+s2, s1-s2, and everything in-between in intervals of 1, so 3/2 and 1/2 ...

i don't get it ... it even says here "We can get any spin between |s-s'| and s+s'. "

and the next part says "On the other hand, if the spin-1/2 particle had m=-1/2, then m_tot = +1/2 and either s_tot = 3/2, or s_tot = 1/2 are allowed"

so i guess 1-(-1/2)=3/2, 1+(-1/2) = 1/2

but isn't the first part also 1-1/2=1/2, 1+1/2 = 3/2

?

so confused :uhh:

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# Adding spins

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