A Construction of An Effective Hamiltonian from Feynman Diagrams : Application to the Light-Front Yukawa Model
نویسنده
چکیده
We study a similarity transformation to construct an effective Hamiltonian systematically, which does not contain particle-numberchanging interactions. We found it very advantageous that the effective Hamiltonian can be obtained from Feynman diagrams, so that we can use the covariant perturbative renormalization procedure. We apply this to the Light-Front Yukawa model as an example and confirm that the ground state does not depend on the transverse cutoff to the second order in the coupling constant.
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