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Running Coupling Constants of Fermions with Masses in Quantum Electro Dynamics and Quantum Chromo Dynamics

Guang-jiong Ni·Guo-hong Yang·Rong-tang Fu·Haibin Wang
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Abstract

Based on a simple but effective regularization-renormalization method (RRM), the running coupling constants (RCC) of fermions with masses in quantum electrodynamics (QED) and quantum chromodynamics (QCD) are calculated by renormalization group equation (RGE). Starting at Q=0 ($Q$ being the momentum transfer), the RCC in QED increases with the increase of $Q$ whereas the RCCs for different flavors of quarks with masses in QCD are different and they increase with the decrease of $Q$ to reach a maximum at low $Q$ for each flavor of quark and then decreases to zero at $Q\longrightarrow 0$. The physical explanation is given.

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Guang-jiong Ni, Guo-hong Yang, Rong-tang Fu, Haibin Wang. 1999-06-15. Running Coupling Constants of Fermions with Masses in Quantum Electro Dynamics and Quantum Chromo Dynamics. https://arxiv.org/abs/hep-ph/9906364

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