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arXiv · 0909.0110

On the ambiguity of field correlators represented by asymptotic perturbation expansions

Irinel Caprini·Jan Fischer·Ivo Vrkoč
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Abstract

Starting from the divergence pattern of perturbation expansions in Quantum Field Theory and the (assumed) asymptotic character of the series, we address the problem of ambiguity of a function determined by the perturbation expansion. We consider functions represented by an integral of the Laplace-Borel type along a general contour in the Borel complex plane. Proving a modified form of the Watson lemma, we obtain a large class of functions having the same asymptotic perturbation expansion. Some remarks on perturbative QCD are made, using the particular case of the Adler function.

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Irinel Caprini, Jan Fischer, Ivo Vrkoč. 2009-09-01. On the ambiguity of field correlators represented by asymptotic perturbation expansions. https://doi.org/10.1088/1751-8113/42/39/395403

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