Gauge invariance of the background average effective action
نویسندگان
چکیده
منابع مشابه
Gauge Invariance in 2pi Effective Actions
The problem of maintaining gauge invariance in the 2PI formulation of QED is discussed. A modified form of the 2PI effective action is suggested in which Ward identities for external (background field) and internal (quantum field) gauge transformations are both satisfied, but in different manners. The residual gauge-fixing dependence in this modified 2PI formulation vanishes in a certain low mo...
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ژورنال
عنوان ژورنال: The European Physical Journal C
سال: 2019
ISSN: 1434-6044,1434-6052
DOI: 10.1140/epjc/s10052-019-7153-1