Recent content by ghbeefcake

  1. G

    Length of spin vector for spin-½ particle

    My answer so far in |S| = √3 /2 *hbar but the question states it must be an angular momentum. Is this an angular momentum or am I missing something? Thanks
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    Undergrad What Insights Can the Feynman Diagram of γ+γ→γ+γ Provide?

    If you have γ+γ→γ+γ what would the Feynman diagram look like (time-ordering implied). I think it will be a square with four photons on each vertex but is this all there is to it or am I missing something?