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arXiv · 2304.02374

On Two-Loop Effective Action of 2D Sigma Model

P. V. Akacevich·A. V. Ivanov
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Abstract

In this paper, we study two-loop contribution to the effective action of a two-dimensional sigma model. We derive a new formula, which can be applicable to a regularization of general type. As examples, we obtain known results for dimensional regularization and investigate new types of cutoff one. Also, we discuss non-local contributions and restrictions on the regularization.

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P. V. Akacevich, A. V. Ivanov. 2023-04-05. On Two-Loop Effective Action of 2D Sigma Model. https://doi.org/10.1140/epjc%2Fs10052-023-11797-0

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