Recent content by lhcQFT

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    Graduate In the interacting scalar field theory, I have a question.

    First of all, I copy the text in my lecture note. - - - - - - - - - - - - - - - - - - - In general, $$e^{-iTH}$$ cannot be written exactly in a useful way in terms of creation and annihilation operators. However, we can do it perturbatively, order by order in the coupling $$ \lambda $$. For...
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    Graduate For the Lagrangian of fermion masses, how do I understand?

    Hello, everyone. I have a one question which is related to the fermion masses. If you see my latex mathematics, you can know what I want to say. Here, L means SU(2) left-handed lepton doublets and R means SU(2) right-handed lepton singlets. So I am too much confusing to understand this...
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    Graduate Orbital angular momentum problem

    Hi, I have a question related to the orbital angular momentum. In the referring to Arfken & Weber Mathematical Methods for physicists-6th edition page 267, "In the relativistic Dirac equation, orbital angular momentum is no longer conserved, but J=L+S is conserved," Here, I want to...
    • lhcQFT
    • Thread
    • Angular Angular momentum Momentum Orbital Orbital angular momentum
    • Replies: 3
    • Forum: Quantum Physics
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    Graduate Question related to the Lorentz Invariance

    Ah.. Thank you for your guide. I make sense how to calculate. :-)
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    Graduate Question related to the Lorentz Invariance

    I have a question related to the Lorentz invariance. (on the book of Mark Srednicki Quantum Field Theory, page 35 prob. 2.9 c) There are representations of \Lambda and S. In order to show that result of problem, I use number of two ways. 1. I expanded \Lambda to infinitesimal form using...