In doing my [tex]\phi^{3}[/tex] theory I didn't know exactly how to count the number of loops in a diagram given the number of vertices, internal and external lines. Is there a general algorithm in doing this? What if we have more than one interaction vertex (e.g. the Standard Model)?(adsbygoogle = window.adsbygoogle || []).push({});

PS. What does it mean when it says my thread has been "moved"?

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# How to compute the number of loops in a Feynman diagram?

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