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A Construction of an Effective Hamiltonian from Feynman Diagrams: Application to the Light-Front Yukawa Model

Yuki Yamamoto
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Abstract

We study a similarity transformation to construct an effective Hamiltonian systematically, which does not contain particle-number-changing interactions, by means of Fukuda-Sawada-Taketani-Okubo's method. We show that such Hamiltonian can be constructed from Feynman diagrams and give rules for constructing it in the Light-Front Yukawa model. We prove that it is renormalized by the familiar covariant perturbative renormalization procedure. It is very advantageous that the effective Hamiltonian can be obtained from our rules {\em immediately}. We also numerically diagonalize it to the second order in the coupling constant as an exercise.

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Yuki Yamamoto. 2001-04-03. A Construction of an Effective Hamiltonian from Feynman Diagrams: Application to the Light-Front Yukawa Model. https://doi.org/10.1143/ptp.106.99

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