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arXiv · 2212.03254

Life at the Landau pole

Paul Romatschke
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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 study 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 $\Lambda_{\overline{\rm MS}}$ with the Landau pole in the O(N) model.

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Paul Romatschke. 2022-12-06. Life at the Landau pole. https://doi.org/10.3390/appliedmath4010003

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