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arXiv · hep-ph/9812437

Gauge-invariant Green's functions for the bosonic sector of the standard model

Andreas Nyffeler·Andreas Schenk
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Abstract

There are many applications in gauge theories where the usually employed framework involving gauge-dependent Green's functions leads to considerable problems. In order to overcome the difficulties invariably tied to gauge dependence, we present a manifestly gauge-invariant approach. We propose a generating functional of appropriately chosen gauge-invariant Green's functions for the bosonic sector of the standard model. Since the corresponding external sources emit one-particle states, these functions yield the same S-matrix elements as those obtained in the usual framework. We evaluate the generating functional for the bosonic sector of the standard model up to the one-loop level and carry out its renormalization in the on-shell scheme. Explicit results for some two-point functions are given. Gauge invariance is manifest at any step of our calculation.

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Andreas Nyffeler, Andreas Schenk. 2000-06-21. Gauge-invariant Green's functions for the bosonic sector of the standard model. https://doi.org/10.1103/physrevd.62.036002

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