I am reading about spin, and I think <S[itex]_{x}[/itex]> represents the measured value of spin along the x component. The same would follow for <S[itex]_{y}[/itex]> and <S[itex]_{z}[/itex]>. I also think I read that we can't measure all three values during an experiment. Once we measure one component, we can't measure the other two. So then I don't really understand what <S> means because it cannot be the total measured spin, since we can only know one component.(adsbygoogle = window.adsbygoogle || []).push({});

Does <S> mean the expectation value of each component?

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# What is <S> ?

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