Recent content by Comanche

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    Graduate Is the Proton-Electron Theory Disproved by Experimental Evidence?

    thanks! only the first question left...
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    Graduate Is the Proton-Electron Theory Disproved by Experimental Evidence?

    Hi, I read Georgi's Lie algebras in Particle Physics 2nd chap5 and have two questions. 1) In the beginning he mentioned Heisenberg regarded neutron is composed as proton and electron, the force between nucleons are exchanging electrons. My question is, what is the experimental evidence...
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    Graduate A question about photon helicity

    Dear everyone, I have a simple question about the helicity of photon. The helicity operator is defined as \hat{\mathbf{S}} \hat{\mathbf{p}}/|\mathbf{p}|. How to show the photon has +1/-1 helicity eigenvalue from this definition? Thank you ~~
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    Graduate How to derive a numerator relation in vertex correction in Peskin p191

    i got it, first by l:=k+yq-zp transform k into l, then remove odd terms of l, then use 6.46
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    Graduate How to derive a numerator relation in vertex correction in Peskin p191

    i.e. thank you very much in advance
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    A question about Lorentz invariance for Klein-Gordon field

    Homework Statement Hi everyone, in Peskin & Schroeder, P36, the derivative part of KG field is transformed as eqn (3.3). But why does the partial derivative itself not transform? Homework Equations \partial_{\mu} \phi (x) \rightarrow \partial_{\mu} ( \phi ( \Lambda^{-1} x) ) = (...