arXiv:2006.13061 · Physical review. D/Physical review. D.
Asymptotic low-temperature behavior of two-dimensional RPN−1 models
Claudio Bonati, Alessio Mauro Franchi, Andrea Pelissetto C, Ettore Vicari
Abstract
We investigate the low-temperature behavior of two-dimensional (2D) ${\mathrm{RP}}^{N\ensuremath{-}1}$ models, characterized by a global $\mathrm{O}(N)$ symmetry and a local ${\mathbb{Z}}_{2}$ symmetry. For $N=3$ we perform large-scale simulations of four different 2D lattice models: two standard lattice models and two different constrained models. We also consider a constrained mixed $\mathrm{O}(3)\text{\ensuremath{-}}{\mathrm{RP}}^{2}$ model for values of the parameters such that vector correlations are always disordered. We find that all these models show the same finite-size scaling (FSS) behavior, and therefore belong to the same universality class. However, these FSS curves differ from those computed in the 2D O(3) $\ensuremath{\sigma}$ model, suggesting the existence of a distinct 2D ${\mathrm{RP}}^{2}$ universality class. We also performed simulations for $N=4$, and the corresponding FSS results also support the existence of an ${\mathrm{RP}}^{3}$ universality class, different from the O(4) one.