Institute of Physics eBooks

Effective field theory of interactions and renormalization

Manuel Valiente, Nikolaj Thomas Zinner

Published Sep 1, 2023• 0 citations

Abstract

Here, we introduce the notion of low-energy interactions in non-relativistic quantum mechanics. The goal is to reproduce low-energy phenomenology only, which generally generates infinities, just as in relativistic quantum field theories. The resulting low-energy theory is called effective field theory of interactions, in analogy with the non-relativistic ‘pionless’ effective field theory widely used in nuclear physics. The predictive power of the effective theory depends upon the renormalizability of the theory, which removes the infinities while obtaining sound low-energy physics. Most of the chapter deals with perturbative and non-perturbative renormalization, which will be subsequently needed throughout the rest of the book.

DOI: 10.1088/978-0-7503-3087-9ch3

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