- #1
thoughtgaze
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is there a discussion somewhere on the notion of an advanced or retarded feynman propagator.
i don't mean the advanced or retarded propagator juxtaposed against the feynman propagator. I mean the feynman propagator itself with a theta step function multiplied by it to effectively give an advanced/retarded feynman propagator.
i don't mean the advanced or retarded propagator juxtaposed against the feynman propagator. I mean the feynman propagator itself with a theta step function multiplied by it to effectively give an advanced/retarded feynman propagator.