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

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 نشر من قبل Nicolo Defenu Dr.
 تاريخ النشر 2020
  مجال البحث فيزياء
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The multi-critical fixed points of $O(N)$ symmetric models cease to exist in the $Ntoinfty$ 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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