{
  "abstract": "An antiferromagnetic second-neighbor interaction favors stripe order in the triangular-lattice Ising antiferromagnet, but uniform stripes cannot satisfy odd periodic boundaries. At each fixed odd size $L\\geq5$, we minimize this interaction over the ground states of the zero-field nearest-neighbor model on an $L\\times L$ torus. We prove a minimum total interface length of $4L$ and classify all $L^2(L^2-1)/2$ selected states. Under the uniform measure on these states, the area fractions of the three stripe orientations approach a uniform distribution over all nonnegative triples summing to one. Thus selection reduces an exponential degeneracy to polynomial growth, while the whole-sample orientation fractions remain broadly distributed. We also derive explicit two-sided entropy-density bounds for periodic spin ground states and honeycomb dimer coverings on $M\\times N$ tori, where $M,N$ are the periods along the two primitive lattice directions. For all $M,N\\geq3$, the errors relative to the bulk residual entropy are bounded by explicit constants times $\\min(M,N)^{-2}$, without an aspect-ratio restriction. These bounds give finite-size accuracy guarantees and control the exponentially small fraction of unperturbed ground states that survive the selection.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2611.00154",
  "author_total": 2,
  "authors": [
    {
      "name": "Weiqi Jiang"
    },
    {
      "name": "Pengcheng Hou"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/2arrjdxsfy0hp.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2611.00154",
  "fulltext_url": null,
  "id": "2arrjdxsfy0hp",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2611.00154",
  "language": null,
  "licence": "CC-BY-4.0",
  "licence_label": "CC BY 4.0",
  "licence_source": "article",
  "licence_url": "http://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "cond-mat.stat-mech"
    ]
  ],
  "openalex": null,
  "pdf_url": "https://arxiv.org/pdf/2611.00154",
  "pmcid": null,
  "pmid": null,
  "published": "2026-11-01",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/2arrjdxsfy0hp.ris",
  "sources": [
    {
      "first_seen": "2026-11-03T12:20:59Z",
      "native_id": "2611.00154",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2611.00154"
    }
  ],
  "subjects": [
    {
      "field": "physics",
      "origin": "arxiv:cond-mat.stat-mech",
      "subfield": "statistical-nonlinear"
    }
  ],
  "title": "Weak-coupling selection and finite-torus entropy in the triangular Ising antiferromagnet",
  "title_text": "Weak-coupling selection and finite-torus entropy in the triangular Ising antiferromagnet",
  "type": "preprint",
  "updated_at": "2026-11-05T15:20:18Z",
  "url": "https://research.draconitic.com/paper/2arrjdxsfy0hp",
  "venue": "arXiv",
  "versions": []
}