On base point freeness in positive characteristic
[Sur la vacuité du lieu-base en caractéristique positive]
Annales scientifiques de l'École Normale Supérieure, Série 4, Tome 48 (2015) no. 5, pp. 1239-1272.

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We prove that if (X,A+B) is a pair defined over an algebraically closed field of positive characteristic such that (X,B) is strongly F-regular, A is ample and KX+A+B is strictly nef, then KX+A+B is ample. Similarly, we prove that for a log pair (X,A+B) with A being ample and B effective, KX+A+B is big if it is nef and of maximal nef dimension. As an application, we establish a rationality theorem for the nef threshold and various results towards the minimal model program in dimension three in positive characteristic.

Nous démontrons que, si (X,A+B) est une paire définie sur un corps algébriquement clos de caractéristique positive telle que (X,B) est fortement F-régulière, A est ample et KX+A+B est strictement nef, alors KX+A+B est ample. De la même manière, nous prouvons que, si (X,A+B) est une paire telle que A est ample et B est grand (« big »), alors une condition nécessaire et suffisante pour que le diviseur KX+A+B soit grand est qu'il soit nef et de dimension nef maximale. Nous utilisons ces résultats pour démontrer un théorème de rationalité pour le seuil nef, ainsi que plusieurs résultats nécessaires au programme des modèles minimaux en caractéristique positive en dimension trois.

Publié le :
DOI : 10.24033/asens.2269
Classification : 14E30, 13A35.
Keywords: Birational geometry, positive characteristic.
Mots-clés : Géométrie birationnele, caractéristique positive.
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     title = {On base point freeness  in positive characteristic},
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Cascini, Paolo; Xu, Hiromu Tanaka Chenyang. On base point freeness  in positive characteristic. Annales scientifiques de l'École Normale Supérieure, Série 4, Tome 48 (2015) no. 5, pp. 1239-1272. doi : 10.24033/asens.2269. http://geodesic.mathdoc.fr/articles/10.24033/asens.2269/

Abhyankar, S. S., Springer Monographs in Math., Springer, 1998, 312 pages | MR | Zbl

Ambro, F. Nef dimension of minimal models, Math. Ann., Volume 330 (2004), pp. 309-322 | MR | Zbl | DOI

Angehrn, U.; Siu, Y. Effective freeness and point separation for adjoint bundles, Invent. Math., Volume 122 (1995), pp. 291-308 | MR | Zbl | DOI

Bauer, T.; Campana, F.; Eckl, T.; Kebekus, S.; Peternell, T.; Rams, S.; Szemberg, T.; Wotzlaw, L. A reduction map for nef line bundles, Complex geometry (Göttingen, 2000), Springer (2002), pp. 27-36 | MR | Zbl | DOI

Birkar, C.; Cascini, P.; Hacon, C. D.; McKernan, J. Existence of minimal models for varieties of log general type, J. Amer. Math. Soc., Volume 23 (2010), pp. 405-468 | MR | Zbl | DOI

Boucksom, S.; Demailly, J.-P.; Păun, M.; Peternell, T. The pseudo-effective cone of a compact Kähler manifold and varieties of negative Kodaira dimension, J. Algebraic Geom., Volume 22 (2013), pp. 201-248 | MR | Zbl | DOI

Bombieri, E.; Mumford, D., Complex analysis and algebraic geometry, Iwanami Shoten, 1977, pp. 23-42 | MR | Zbl | DOI

Cossart, V.; Piltant, O. Resolution of singularities of threefolds in positive characteristic. I. Reduction to local uniformization on Artin-Schreier and purely inseparable coverings, J. Algebra, Volume 320 (2008), pp. 1051-1082 (ISSN: 0021-8693) | MR | Zbl | DOI

Cossart, V.; Piltant, O. Resolution of singularities of threefolds in positive characteristic. II, J. Algebra, Volume 321 (2009), pp. 1836-1976 | MR | Zbl | DOI

Campana, F.; Peternell, T. Algebraicity of the ample cone of projective varieties, J. reine angew. Math., Volume 407 (1990), pp. 160-166 | MR | Zbl

Cutkosky, S., Graduate Studies in Math., 63, Amer. Math. Soc., 2004, 186 pages | MR | Zbl

Eisenbud, D., Graduate Texts in Math., 150, Springer, 1995 | MR | Zbl

Gruson, L.; Raynaud, M. Critères de platitude et de projectivité. Techniques de “platification” d'un module, Invent. Math., Volume 13 (1971), pp. 1-89 | MR | Zbl | DOI

Hartshorne, R., Lecture Notes in Math., 156, Springer, 1970 | MR | Zbl

Hochster, M.; Huneke, C. Tight closure, invariant theory, and the Briançon-Skoda theorem, J. Amer. Math. Soc., Volume 3, pp. 31-116 | MR | Zbl

Hacon, C. D.; Xu, C. On the three dimensional minimal model program in positive characteristic (preprint arXiv:1302.0298 ) | MR

Kawamata, Y. Subadjunction of log canonical divisors for a subvariety of codimension 2, Birational algebraic geometry (Baltimore, MD, 1996) (Contemp. Math.), Volume 207 (1997), pp. 79-88 | MR | Zbl | DOI

Keel, S. Intersection theory of moduli space of stable n-pointed curves of genus zero, Trans. Amer. Math. Soc., Volume 330 (1992), pp. 545-574 (ISSN: 0002-9947) | MR | Zbl

Keel, S. Basepoint freeness for nef and big line bundles in positive characteristic, Ann. of Math., Volume 149 (1999), pp. 253-286 | MR | Zbl | DOI

Kleiman, S., Fundamental algebraic geometry (Math. Surveys Monogr.), Volume 123, Amer. Math. Soc., 2005, pp. 235-321 | MR

Kollár, J.; Mori, S., Cambridge Tracts in Mathematics, 134, Cambridge Univ. Press, 254 pages | MR | Zbl

Kawamata, Y.; Matsuda, K.; Matsuki, K. Algebraic geometry, Sendai, 1985, Adv. Stud. Pure Math., 10, North-Holland, 1987, pp. 283-360 | MR | Zbl | DOI

Keel, S.; Matsuki, K.; McKernan, J. Log abundance theorem for threefolds, Duke Math. J., Volume 75 (1994), pp. 99-119 | MR | Zbl | DOI

Kollár, J., Cambridge Tracts in Mathematics, 200, Cambridge Univ. Press, 2013, 370 pages | MR | Zbl

Kollár, J. Extremal rays on smooth threefolds, Ann. Sci. École Norm. Sup., Volume 24 (1991), pp. 339-361 | MR | Zbl | mathdoc-id | DOI

Kollár, J., Ergebn. Math. Grenzg., 32, Springer, 1996 | MR | Zbl

Lazarsfeld, R., Ergebn. Math. Grenzg., 48, Springer, Berlin, 2004, 387 pages (ISBN: 3-540-22533-1) | DOI | MR

Miyaoka, Y.; Mori, S. A Numerical Criterion for Uniruledness, Ann. of Math., Volume 124 (1986), pp. 65-69 | MR | Zbl | DOI

Mori, S. Threefolds whose canonical bundles are not numerically effective, Ann. of Math., Volume 116 (1982), pp. 133-176 | MR | Zbl | DOI

Mehta, V. B.; Subramanian, S. Nef line bundles which are not ample, Math. Z., Volume 219 (1995), pp. 235-244 | MR | Zbl | DOI

Mustaţă, M.; Takagi, S.; Watanabe, K. F-thresholds and Bernstein-Sato polynomials, European Congress of Mathematics (2005), pp. 341-364 | MR | Zbl

Prokhorov, Y. G.; Shokurov, V. V. Towards the second main theorem on complements, J. Algebraic Geom., Volume 18 (2009), pp. 151-199 (ISSN: 1056-3911) | MR | Zbl | DOI

Schwede, K. F-adjunction, Algebra & Number Theory, Volume 3 (2009), pp. 907-950 | MR | Zbl | DOI

Schwede, K.; Smith, K. E. Globally F-regular and log Fano varieties, Adv. Math., Volume 224 (2010), pp. 863-894 | MR | Zbl | DOI

Tanaka, H. Minimal models and abundance for positive characteristic log surfaces (preprint arXiv:1201.5699, to appear in Nagoya Math. J ) | MR

Tanaka, H. The trace map of Frobenius and extending sections for threefolds (preprint arXiv:1302.3134 ) | MR

McKernan, J. private Communication (2013)

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