The fate of $O(N)$ multi-critical universal behaviour

Nicolò Defenu; Alessandro Codello

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arXiv · 2005.10827

The fate of $O(N)$ multi-critical universal behaviour

Nicolò Defenu·Alessandro Codello

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Abstract

The multi-critical fixed points of $O(N)$ symmetric models cease to exist in the $N\to\infty$ limit, but the mechanism regulating their annihilation still presents several enigmatic aspects. Here, we explore the evolution of high-order multi-critical points in the $(d,N)$ plane and uncover a complex mosaics for their asymptotic behaviour at large $N$. This picture is confirmed by various RG approaches and constitutes a fundamental step towards the full comprehension of critical behaviour in $O(N)$ field theories.

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Nicolò Defenu, Alessandro Codello. 2020-05-21. The fate of $O(N)$ multi-critical universal behaviour. https://arxiv.org/abs/2005.10827

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