Hi all,(adsbygoogle = window.adsbygoogle || []).push({});

Doing a graduate QFT course.

We've been looking at the bilinear expressions involving the adjoint spinor and the gamma matrices and how the various combinations transform as scalars, vectors etc.

My question is this:

Other than just appreciating the fact that various combinations of these bilinears transform analogously to scalars, pseudoscalars etc - what is thepointof them. i.e what is the justification of their existence, why are the useful, when would one use them etc.

Thanks in advance!

Rich

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# Bilinear Expressions

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