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arXiv · 2101.03075

Critical points in the $RP^{N-1}$ model

Youness Diouane·Noel Lamsen·Gesualdo Delfino
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Abstract

The space of solutions of the exact renormalization group fixed point equations of the two-dimensional $RP^{N-1}$ model, which we recently obtained within the scale invariant scattering framework, is explored for continuous values of $N\geq 0$. Quasi-long-range order occurs only for $N=2$, and allows for several lines of fixed points meeting at the BKT transition point. A rich pattern of fixed points is present below $N^*=2.24421..$, while only zero temperature criticality in the $O(N(N+1)/2-1)$ universality class can occur above this value. The interpretation of an extra solution at $N=3$ requires the identitication of a path to criticality specific to this value of $N$.

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Youness Diouane, Noel Lamsen, Gesualdo Delfino. 2021-01-08. Critical points in the $RP^{N-1}$ model. https://doi.org/10.1088/1742-5468%2Fabe6fc

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