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arXiv · 2005.14558

Optical theorem and effective action: new proofs of old results in QFT

Sergio L. Cacciatori·Andrea Zanzi
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Abstract

A new proof of the optical theorem at all orders is presented. Although the theorem is a well-known result in Quantum Field Theory, our proof is interesting because it is particularly simple. Indeed, the theorem is a direct consequence of the pole-ology formalism discussed in Weinberg's Cambridge books. We also discuss a new proof of the standard result concerning the effective action as generating functional of 1PI contributions.

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Sergio L. Cacciatori, Andrea Zanzi. 2020-05-29. Optical theorem and effective action: new proofs of old results in QFT. https://arxiv.org/abs/2005.14558

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