English

Three-loop singularity structure for a non-linear sigma model

High Energy Physics - Theory 2025-07-09 v1 Mathematical Physics math.MP

Abstract

The paper is devoted to the three-loop renormalization of the effective action for a two-dimensional non-linear sigma model using the background field method and a cutoff regularization in the coordinate representation. The coefficients of the renormalization constant and the necessary auxiliary vertices are found, as well as the asymptotic expansions of all three-loop diagrams, and their dependence on the type of regularizing function. A comparison is also made with the standard case of cutoff in the momentum representation.

Keywords

Cite

@article{arxiv.2507.05923,
  title  = {Three-loop singularity structure for a non-linear sigma model},
  author = {P. V. Akacevich and A. V. Ivanov and I. V. Korenev},
  journal= {arXiv preprint arXiv:2507.05923},
  year   = {2025}
}

Comments

LaTeX, 64 pages, 179 figures. Firstly appeared in Russian, July 7, 2025, see https://www.pdmi.ras.ru/preprint/2025/25-08.html