{
  "abstract": "We study torus surgery on the Cartwright--Steger surface and the degree-two cover construction proposed in \\cite[Remark~1]{ASY}. Every torus in this surface is integrally nullhomologous, and surgery on a fixed disjoint collection of such tori cannot decrease the first Betti number. We then determine the nodal-curve subgroup and complete the fundamental-group calculation in the degree-two construction. The resulting minimal symplectic manifold has signature zero and fundamental group $\\Z/2$; for compatible symplectic gluings, its universal cover is an exotic symplectic $31\\CP^2\\#31\\overline{\\CP}^{\\,2}$. The construction on the original Cartwright--Steger surface gives a minimal symplectic manifold with signature $-1$ and fundamental group $(\\Z/2)^2$.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2610.06442",
  "author_total": 2,
  "authors": [
    {
      "name": "Anar Akhmedov"
    },
    {
      "name": "Sai-Kee Yeung"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/4zp8xb8g757f0.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2610.06442",
  "fulltext_url": null,
  "id": "4zp8xb8g757f0",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2610.06442",
  "language": null,
  "licence": "LicenseRef-arXiv-nonexclusive-1.0",
  "licence_label": "arXiv licence",
  "licence_source": "article",
  "licence_url": "http://arxiv.org/licenses/nonexclusive-distrib/1.0/",
  "metadata_licence": "CC0-1.0",
  "native_subjects": [
    [
      "arxiv",
      "math.GT"
    ],
    [
      "arxiv",
      "math.SG"
    ],
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      "openalex",
      "2608|Geometric and Algebraic Topology"
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  ],
  "openalex": "W7220711483",
  "pdf_url": "https://arxiv.org/pdf/2610.06442",
  "pmcid": null,
  "pmid": null,
  "published": "2026-10-05",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/4zp8xb8g757f0.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:27:10Z",
      "native_id": "2610.06442",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2610.06442"
    }
  ],
  "subjects": [
    {
      "field": "mathematics",
      "origin": "arxiv:math.GT",
      "subfield": "geometry-topology"
    }
  ],
  "title": "Torus Surgery Constraints and Intermediate Covers of the Cartwright--Steger Surface",
  "title_text": "Torus Surgery Constraints and Intermediate Covers of the Cartwright--Steger Surface",
  "type": "preprint",
  "updated_at": "2026-10-30T12:27:10Z",
  "url": "https://research.draconitic.com/paper/4zp8xb8g757f0",
  "venue": "arXiv",
  "versions": []
}