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arXiv · 2405.08153

Coupling renormalization flow in the strongly interacting regime of an asymptotically free quantum field theory in four dimensions

Jürgen Berges·Razvan Gurau·Hannes Keppler·Thimo Preis
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Abstract

We consider a scalar quantum field theory with global $O(N)^3$ symmetry in four Euclidean dimensions and solve it numerically in closed form in the large-N limit. For imaginary tetrahedral coupling the theory is asymptotically free, with stable and real quantum effective action. We demonstrate the dynamical build-up of a strong interaction as the correlation length increases in a regime where the coupling renormalization flow remains well defined in the infrared. This is in contrast to perturbative results of asymptotically free theories, which predict that the coupling becomes ill-defined in the infrared, like in quantum chromodynamics. These properties make the model an important laboratory for the study of strong-coupling phenomena in quantum field theory from first principles.

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Jürgen Berges, Razvan Gurau, Hannes Keppler, Thimo Preis. 2024-05-13. Coupling renormalization flow in the strongly interacting regime of an asymptotically free quantum field theory in four dimensions. https://doi.org/10.1103/physrevd.110.036007

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