Hey, I'm doing some examples in QFT and I don't want to go too far with this one:(adsbygoogle = window.adsbygoogle || []).push({});

Doing gauge symmetries, we first introduce the Unitary spacetime-dependent gauge transformation that gives us a gauge potential. With the new gauge added Lagrangian, I want to take its variation to confirm the equations of motion. Here's my question.

When we take [tex]\frac{d}{d \phi} -m^2\phi^*\phi [/tex] for example...

how do we handle the complex conjugate through our variation?

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# Variation of simple Lagrangian

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