Gauge-Dependence of Green’s Functions in QCD and QED
نویسنده
چکیده
When all Green’s functions are known in a given gauge we may raise a question of whether it is possible or not to derive the corresponding ones in a different gauge. The answer is negative in QCD but affirmative in QED provided that we confine ourselves to the covariant gauge characterized by a gauge parameter α. We shall discuss the physical significance of this conclusion.
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