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arXiv · 2011.09897

From perturbative to non-perturbative in the O(4) sigma model

Michael C. Abbott·Zoltán Bajnok·János Balog·Árpád Hegedűs
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Abstract

We study the resurgent trans-series for the free energy of the two-dimensional O(4) sigma model in a magnetic field. Exploiting integrability, we obtain very high-order perturbative data, from which we can explore non-perturbative sectors. We are able to determine exactly the leading real-valued exponentially small terms, which we check against the direct numerical solution of the exact integral equation, and find complete agreement.

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Michael C. Abbott, Zoltán Bajnok, János Balog, Árpád Hegedűs. 2021-05-16. From perturbative to non-perturbative in the O(4) sigma model. https://doi.org/10.1016/j.physletb.2021.136369

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