{ "id": "math/0603736", "version": "v2", "published": "2006-03-31T09:42:11.000Z", "updated": "2007-08-06T10:08:19.000Z", "title": "On Q-conic bundles", "authors": [ "Shigefumi Mori", "Yuri Prokhorov" ], "comment": "54 pages, LaTeX", "journal": "Publ. Res. Inst. Math. Sci., 2008, 44, 315-369", "categories": [ "math.AG" ], "abstract": "A $\\mathbb Q$-conic bundle is a proper morphism from a threefold with only terminal singularities to a normal surface such that fibers are connected and the anti-canonical divisor is relatively ample. We study the structure of $\\mathbb Q$-conic bundles near their singular fibers. One corollary to our main results is that the base surface of every $\\mathbb Q$-conic bundle has only Du Val singularities of type A (a positive solution of a conjecture by Iskovskikh). We obtain the complete classification of $\\mathbb Q$-conic bundles under the additional assumption that the singular fiber is irreducible and the base surface is singular.", "revisions": [ { "version": "v2", "updated": "2007-08-06T10:08:19.000Z" } ], "analyses": { "subjects": [ "14J30", "14E35", "14E30" ], "keywords": [ "q-conic bundles", "singular fiber", "base surface", "additional assumption", "normal surface" ], "tags": [ "journal article" ], "note": { "typesetting": "LaTeX", "pages": 54, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2006math......3736M" } } }