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On critical models with $Nleq 4$ scalars in $d=4-epsilon$

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 نشر من قبل Omar Zanusso
 تاريخ النشر 2020
  مجال البحث فيزياء
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We adopt a combination of analytical and numerical methods to study the renormalization group flow of the most general field theory with quartic interaction in $d=4-epsilon$ with $N=3$ and $N=4$ scalars. For $N=3$, we find that it admits only three nondecomposable critical points: the Wilson-Fisher with $O(3)$ symmetry, the cubic with $H_3=(mathbb{Z}_2)^3rtimes S_3$ symmetry, and the biconical with $O(2)times mathbb{Z}_2$. For $N=4$, our analysis reveals the existence of new nontrivial solutions with discrete symmetries and with up to three distinct field anomalous dimensions.



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