Third-order transitions in Ising and Potts models on Watts--Strogatz small-world networks

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Wang, Fangfang, Liu, Wei, Zhang, Ke, He, Yongjian, Qi, Kai, Tang, Ying, Di, Zengru
Format: Preprint
Published: 2026
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866914387549224960
author Wang, Fangfang
Liu, Wei
Zhang, Ke
He, Yongjian
Qi, Kai
Tang, Ying
Di, Zengru
author_facet Wang, Fangfang
Liu, Wei
Zhang, Ke
He, Yongjian
Qi, Kai
Tang, Ying
Di, Zengru
contents We study third-order transitions in the two-dimensional Ising and Potts model on regular lattices and Watts--Strogatz small-world networks. Cluster observables are used to track post-critical boundary reorganization and pre-critical cluster breakup. For the Ising model, the critical temperature $T_c$ is calibrated independently from Binder-cumulant crossings and susceptibility peaks, whereas for the Potts model on small-world networks it is identified operationally from the dominant critical peak of $\mathrm d\langle P\rangle/\mathrm dT$. The independent and dependent third-order transitions are identified from the isolated-spin peak and the post-critical structural extremum, respectively. For both lattice and small-world topologies, we find the robust ordering $T_{\mathrm{ind}}<T_c<T_{\mathrm{dep}}$. Increasing the rewiring probability shifts all three characteristic temperatures upward and enhances the visibility of the post-critical transition. The effect is especially clear in the Potts model, where perimeter-based observables are more sensitive to multistate boundary fluctuations. The systematic persistence of the characteristic temperature hierarchy across topologies and finite sizes argues against interpreting these features as incidental finite-size irregularities. Instead, our results support their interpretation as genuine third-order transitions whose structural detectability can be amplified by network topology.
format Preprint
id arxiv_https___arxiv_org_abs_2603_11522
institution arXiv
publishDate 2026
record_format arxiv
spellingShingle Third-order transitions in Ising and Potts models on Watts--Strogatz small-world networks
Wang, Fangfang
Liu, Wei
Zhang, Ke
He, Yongjian
Qi, Kai
Tang, Ying
Di, Zengru
Statistical Mechanics
We study third-order transitions in the two-dimensional Ising and Potts model on regular lattices and Watts--Strogatz small-world networks. Cluster observables are used to track post-critical boundary reorganization and pre-critical cluster breakup. For the Ising model, the critical temperature $T_c$ is calibrated independently from Binder-cumulant crossings and susceptibility peaks, whereas for the Potts model on small-world networks it is identified operationally from the dominant critical peak of $\mathrm d\langle P\rangle/\mathrm dT$. The independent and dependent third-order transitions are identified from the isolated-spin peak and the post-critical structural extremum, respectively. For both lattice and small-world topologies, we find the robust ordering $T_{\mathrm{ind}}<T_c<T_{\mathrm{dep}}$. Increasing the rewiring probability shifts all three characteristic temperatures upward and enhances the visibility of the post-critical transition. The effect is especially clear in the Potts model, where perimeter-based observables are more sensitive to multistate boundary fluctuations. The systematic persistence of the characteristic temperature hierarchy across topologies and finite sizes argues against interpreting these features as incidental finite-size irregularities. Instead, our results support their interpretation as genuine third-order transitions whose structural detectability can be amplified by network topology.
title Third-order transitions in Ising and Potts models on Watts--Strogatz small-world networks
topic Statistical Mechanics
url https://arxiv.org/abs/2603.11522