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DOE OSTI · 2339801

Life at the Landau Pole

Romatschke, Paul
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Abstract

If a quantum field theory has a Landau pole, the theory is usually called ‘sick’ and dismissed as a candidate for an interacting UV-complete theory. In a recent study on the interacting 4d O(N) model at large N, it was shown that at the Landau pole, observables remain well-defined and finite. In this work, I investigate both relevant and irrelevant deformations of the said model at the Landau pole, finding that physical observables remain unaffected. Apparently, the Landau pole in this theory is benign. As a phenomenological application, I compare the O(N) model to QCD by identifying $Λ_{\overline{MS}}$ with the Landau pole in the O(N) model.

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73 NUCLEAR PHYSICS AND RADIATION PHYSICSlarge N field theorynon-perturbative methodsquantum field theory

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Romatschke, Paul. 2024-01-01. Life at the Landau Pole. https://doi.org/10.3390/appliedmath4010003

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