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arXiv · 2203.01253

Modifying the Dyson Series for Unstable Particles and Resonances

Peter Matak
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Abstract

In this work, we introduce a modification of the Dyson series based on the perturbative unitarity as a starting point. The presented approach systematically avoids singularities and double-counting related to the presence of unstable particles as intermediate states and, at the same time, it does not rely on a specific choice of the renormalization scheme.

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Peter Matak. 2022-03-02. Modifying the Dyson Series for Unstable Particles and Resonances. https://doi.org/10.1103/physrevd.105.076019

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