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On the Gauge-Independence of the S-Matrix

W. Kummer
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Abstract

The S-matrix is invariant with respect to the variation of any (global) parameter involved in the gauge fixing conditions, if that variation is accompanied by a certain redefinition of the basis of polarization vectors. Renormalizability of the underlying gauge theory is not required. The proof is nonperturbative and, using the `extended' BRS transformation, quite simple.

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W. Kummer. 2001-04-19. On the Gauge-Independence of the S-Matrix. https://doi.org/10.1007/s100520100709

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