{
  "abstract": "We construct infinitely many pairwise non-diffeomorphic irreducible smooth four-manifolds homeomorphic to ${\\mathbb {CP}}^2\\# 7{\\overline {\\mathbb {C}} {\\mathbb {P}} } ^2$, each admitting a free, orientation-preserving involution. Their quotients give infinitely many irreducible definite four-manifolds with fundamental group ${\\mathbb {Z}}/2 {\\mathbb {Z}}$ and $b_2=3$, filling the corresponding gap in the geography of such examples. The construction of infinitely many distinct examples relies on a novel equivariant torus surgery.",
  "abstract_shown": true,
  "affiliations": [],
  "article_type": null,
  "arxiv": "2609.26450",
  "author_total": 3,
  "authors": [
    {
      "name": "R. İnanç Baykur"
    },
    {
      "name": "András I. Stipsicz"
    },
    {
      "name": "Zoltán Szabó"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/8cp05vj1e5vp0.bib",
  "cited_by": 0,
  "doi": "10.48550/arxiv.2609.26450",
  "fulltext_url": null,
  "id": "8cp05vj1e5vp0",
  "issns": [],
  "landing_url": "https://arxiv.org/abs/2609.26450",
  "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",
      "math.GT"
    ],
    [
      "openalex",
      "2608|Geometric and Algebraic Topology"
    ]
  ],
  "openalex": "W7214065675",
  "pdf_url": "https://arxiv.org/pdf/2609.26450",
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-22",
  "publisher": null,
  "ris": "https://research.draconitic.com/paper/8cp05vj1e5vp0.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:23:43Z",
      "native_id": "2609.26450",
      "source": "arxiv",
      "url": "https://arxiv.org/abs/2609.26450"
    }
  ],
  "subjects": [
    {
      "field": "mathematics",
      "origin": "arxiv:math.GT",
      "subfield": "geometry-topology"
    }
  ],
  "title": "Irreducible exotic ${\\mathbb {CP}}^2\\# 7{\\overline {\\mathbb {C}} {\\mathbb {P}} } ^2$'s with free involutions",
  "title_text": "Irreducible exotic ℂℙ^2# 7ℂ̅ ℙ ^2's with free involutions",
  "type": "preprint",
  "updated_at": "2026-10-30T12:23:43Z",
  "url": "https://research.draconitic.com/paper/8cp05vj1e5vp0",
  "venue": "arXiv",
  "versions": []
}