{ "id": "2404.04790", "version": "v1", "published": "2024-04-07T02:39:04.000Z", "updated": "2024-04-07T02:39:04.000Z", "title": "Global $F$-regularity for weak del Pezzo surfaces", "authors": [ "Tatsuro Kawakami", "Hiromu Tanaka" ], "comment": "17 pages", "categories": [ "math.AG" ], "abstract": "Let $k$ be an algebraically closed field of characteristic $p>0$. Let $X$ be a normal projective surface over $k$ with canonical singularities whose anti-canonical divisor is nef and big. We prove that $X$ is globally $F$-regular except for the following cases: (1) $K_X^2=4$ and $p=2$, (2) $K_X^2=3$ and $p \\in \\{2, 3\\}$, (3) $K_X^2=2$ and $p \\in \\{2, 3\\}$, (4) $K_X^2=1$ and $p \\in \\{2, 3, 5\\}$. For each degree $K_X^2$, the assumption of $p$ is optimal.", "revisions": [ { "version": "v1", "updated": "2024-04-07T02:39:04.000Z" } ], "analyses": { "subjects": [ "14J45", "13A35" ], "keywords": [ "weak del pezzo surfaces", "regularity", "normal projective surface", "characteristic", "algebraically closed field" ], "note": { "typesetting": "TeX", "pages": 17, "language": "en", "license": "arXiv", "status": "editable" } } }