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arXiv · 1810.02646

How (not) to renormalize integral equations with singular potentials in effective field theory

E. Epelbaum·A. M. Gasparyan·J. Gegelia·Ulf-G. Meißner
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Abstract

We discuss the connection between the perturbative and non-perturbative renormalization and related conceptual issues in the few-nucleon sector of the low-energy effective field theory of the strong interactions. General arguments are supported by examples from effective theories with and without pions as dynamical degrees of freedom. A quantum mechanical potential with explicitly specified short- and long-range parts is considered as an "underlying fundamental theory" and the corresponding effective field theory potential is constructed. Further, the problem of the effective field theoretical renormalization of the Skornyakov-Ter-Martyrosian equation is revisited.

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E. Epelbaum, A. M. Gasparyan, J. Gegelia, Ulf-G. Meißner. 2018-10-05. How (not) to renormalize integral equations with singular potentials in effective field theory. https://doi.org/10.1140/epja/i2018-12632-1

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