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Multicritical points of the O(N) scalar theory in $2<d<4$ for large N

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 نشر من قبل Nikolaos Tetradis
 تاريخ النشر 2018
  مجال البحث فيزياء
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We solve analytically the renormalization-group equation for the potential of the O(N)-symmetric scalar theory in the large-N limit and in dimensions 2<d<4, in order to look for nonperturbative fixed points that were found numerically in a recent study. We find new real solutions with singularities in the higher derivatives of the potential at its minimum, and complex solutions with branch cuts along the negative real axis.



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