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arXiv · hep-ph/9811398

Mass and Coupling Constant Limits from Convergence Conditions on the Effective Charge in QED

J. H. Field
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Abstract

The massless fermion limit of QED is discussed. For on-shell renormalisation the high energy behaviour fixes no lower limit on the mass of the lightest fermion if the fine structure constant $α$ is allowed to vary. The choice of an arbitary (space-like) subtraction point does, however, fix a lower limit on the mass of the lightest fermion, for any subtraction scale $μ$, if the effective charge $\aefmu$ respects both quantum mechanical superposition and renormalisation scale invariance. Limits on the values of $α$ or the electron mass are obtained within the Standard Electroweak Model by requiring convergence of $\aefmz$.

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J. H. Field. 2000-03-20. Mass and Coupling Constant Limits from Convergence Conditions on the Effective Charge in QED. https://doi.org/10.1142/s0217751x00001105

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