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arXiv · hep-th/9702096

Ward - Takahashi identities and Noether's theorem in quantum field theory

Michael Danos
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Abstract

A gap in the mathematical logic in derivations in quantum field theory arises as consequence of variation before quantization. To close this gap the present paper introduces a mathematically rigorous variational calculus for operator fields. Using quantization before variation it is demonstrated that the so-called naive results are correct; in particular both Noether's theorem and the Ward-Takahashi identities retain full validity in quantum field theory.

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Michael Danos. 1997-02-12. Ward - Takahashi identities and Noether's theorem in quantum field theory. https://doi.org/10.1007/bf02551149

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