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arXiv · 2110.04014

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

Youness Diouane·Noel Lamsen·Gesualdo Delfino
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Abstract

We use scale invariant scattering theory to obtain the exact equations determining the renormalization group fixed points of the two-dimensional $CP^{N-1}$ model, for $N$ real. Also due to special degeneracies at $N=2$ and 3, the space of solutions for $N\geq 2$ reduces to that of the $O(N^2-1)$ model, and accounts for a zero temperature critical point. For $N<2$ the space of solutions becomes larger than that of the $O(N^2-1)$ model, with the appearance of new branches of fixed points relevant for criticality in gases of intersecting loops.

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Youness Diouane, Noel Lamsen, Gesualdo Delfino. 2021-10-08. Critical points in the $CP^{N-1}$ model. https://doi.org/10.1088/1742-5468%2Fac4983

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