Quotients of groups of birational transformations of cubic del Pezzo fibrations
[Quotients de groupes de transformations birationnelles de fibrations en del Pezzo cubiques]
Journal de l’École polytechnique — Mathématiques, Tome 7 (2020), pp. 1089-1112.

Nous démontrons que le groupe des transformations birationnelles d’une fibration de del Pezzo de degré 3 sur une courbe n’est pas simple, en donnant un homomorphisme de groupes surjectif vers un produit libre d’une infinité de groupes d’ordre 2. Par conséquent, nous obtenons que le groupe de Cremona de rang 3 n’est pas engendré par les applications birationnelles qui préservent une fibration rationnelles. De plus, le sous-groupe de Bir( 3 ) engendré par tous les sous-groupes algébriques connexes est un sous-groupe distingué propre.

We prove that the group of birational transformations of a del Pezzo fibration of degree 3 over a curve is not simple, by giving a surjective group homomorphism to a free product of infinitely many groups of order 2. As a consequence we also obtain that the Cremona group of rank 3 is not generated by birational maps preserving a rational fibration. Besides, the subgroup of Bir( 3 ) generated by all connected algebraic subgroups is a proper normal subgroup.

Reçu le :
Accepté le :
Publié le :
DOI : 10.5802/jep.136
Classification : 14E07, 14E05, 14E30, 14J45, 14M22
Keywords: Del Pezzo fibrations, Cremona group, group homomorphisms, group quotients, birational transformations, genus
Mot clés : Fibrations de del Pezzo, groupe de Cremona, homomorphismes de groupes, quotients de groupes, transformations birationnelles, genre

Jérémy Blanc 1 ; Egor Yasinsky 1

1 Universität Basel, Departement Mathematik und Informatik Spiegelgasse 1, CH-4051 Basel, Switzerland
Licence : CC-BY 4.0
Droits d'auteur : Les auteurs conservent leurs droits
@article{JEP_2020__7__1089_0,
     author = {J\'er\'emy Blanc and Egor Yasinsky},
     title = {Quotients of groups of birational transformations of cubic del {Pezzo} fibrations},
     journal = {Journal de l{\textquoteright}\'Ecole polytechnique {\textemdash} Math\'ematiques},
     pages = {1089--1112},
     publisher = {\'Ecole polytechnique},
     volume = {7},
     year = {2020},
     doi = {10.5802/jep.136},
     language = {en},
     url = {https://jep.centre-mersenne.org/articles/10.5802/jep.136/}
}
TY  - JOUR
AU  - Jérémy Blanc
AU  - Egor Yasinsky
TI  - Quotients of groups of birational transformations of cubic del Pezzo fibrations
JO  - Journal de l’École polytechnique — Mathématiques
PY  - 2020
SP  - 1089
EP  - 1112
VL  - 7
PB  - École polytechnique
UR  - https://jep.centre-mersenne.org/articles/10.5802/jep.136/
DO  - 10.5802/jep.136
LA  - en
ID  - JEP_2020__7__1089_0
ER  - 
%0 Journal Article
%A Jérémy Blanc
%A Egor Yasinsky
%T Quotients of groups of birational transformations of cubic del Pezzo fibrations
%J Journal de l’École polytechnique — Mathématiques
%D 2020
%P 1089-1112
%V 7
%I École polytechnique
%U https://jep.centre-mersenne.org/articles/10.5802/jep.136/
%R 10.5802/jep.136
%G en
%F JEP_2020__7__1089_0
Jérémy Blanc; Egor Yasinsky. Quotients of groups of birational transformations of cubic del Pezzo fibrations. Journal de l’École polytechnique — Mathématiques, Tome 7 (2020), pp. 1089-1112. doi : 10.5802/jep.136. https://jep.centre-mersenne.org/articles/10.5802/jep.136/

[BB73] A. Białynicki-Birula - “On fixed point schemes of actions of multiplicative and additive groups”, Topology 12 (1973), p. 99-103 | DOI | MR | Zbl

[BCDP19] J. Blanc, I. Cheltsov, A. Duncan & Y. Prokhorov - “Birational transformations of threefolds of (un)-bounded genus or gonality”, 2019 | arXiv

[BCHM10] C. Birkar, P. Cascini, C. D. Hacon & J. McKernan - “Existence of minimal models for varieties of log general type”, J. Amer. Math. Soc. 23 (2010) no. 2, p. 405-468 | DOI | MR | Zbl

[BF13] J. Blanc & J.-P. Furter - “Topologies and structures of the Cremona groups”, Ann. of Math. (2) 178 (2013) no. 3, p. 1173-1198 | DOI | MR | Zbl

[BFT19] J. Blanc, A. Fanelli & R. Terpereau - “Connected algebraic groups acting on 3-dimensional Mori fibrations”, 2019 | arXiv

[Bir16] C. Birkar - “Singularities of linear systems and boundedness of Fano varieties”, 2016 | arXiv | Zbl

[Bir19] C. Birkar - “Anti-pluricanonical systems on Fano varieties”, Ann. of Math. (2) 190 (2019) no. 2, p. 345-463 | DOI | MR | Zbl

[BLZ19] J. Blanc, S. Lamy & S. Zimmermann - “Quotients of higher dimensional Cremona groups”, 2019, Acta Math. (to appear) | arXiv

[Bro06] R. Brown - Topology and groupoids, BookSurge, LLC, Charleston, SC, 2006 | Zbl

[Can13] S. Cantat - “The Cremona group in two variables”, in European Congress of Mathematics, European Mathematical Society, Zürich, 2013, p. 211-225 | MR | Zbl

[Cas01] G. Castelnuovo - “Le transformazioni generatrici del gruppo Cremoniano nel piano”, Atti Accad. Sci. Torino Cl. Sci. Fis. Mat. Natur. 36 (1901), p. 861-874 | Zbl

[CL13] S. Cantat & S. Lamy - “Normal subgroups in the Cremona group”, Acta Math. 210 (2013) no. 1, p. 31-94, With an appendix by Yves de Cornulier | DOI | MR | Zbl

[DI09] I. V. Dolgachev & V. A. Iskovskikh - “Finite subgroups of the plane Cremona group”, in Algebra, arithmetic, and geometry: in honor of Yu. I. Manin. Vol. I, Progress in Math., vol. 269, Birkhäuser Boston, Boston, MA, 2009, p. 443-548 | DOI | MR | Zbl

[Dés19] J. Déserti - “The Cremona group and its subgroups”, 2019 | arXiv | Zbl

[Giz82] M. K. Gizatullin - “Defining relations for the Cremona group of the plane”, Izv. Akad. Nauk SSSR Ser. Mat. 46 (1982) no. 5, p. 909-970, English translation in Math. USSR 21 (1983), no. 2, p. 211–268 | MR | Zbl

[Har81] J. Harris - “A bound on the geometric genus of projective varieties”, Ann. Scuola Norm. Sup. Pisa Cl. Sci. (4) 8 (1981) no. 1, p. 35-68 | Numdam | MR | Zbl

[HK00] Y. Hu & S. Keel - “Mori dream spaces and GIT”, Michigan Math. J. 48 (2000), p. 331-348 | DOI | MR | Zbl

[HM13] C. D. Hacon & J. McKernan - “The Sarkisov program”, J. Algebraic Geom. 22 (2013) no. 2, p. 389-405 | DOI | MR | Zbl

[IKT93] V. A. Iskovskikh, F. K. Kabdykairov & S. L. Tregub - “Relations in a two-dimensional Cremona group over a perfect field”, Izv. Ross. Akad. Nauk Ser. Mat. 57 (1993) no. 3, p. 3-69, English transl. in Russian Acad. Sci. Izv. Math. 42 (1994), no. 3, p. 427–478 | DOI | Zbl

[Isk96] V. A. Iskovskikh - “Factorization of birational mappings of rational surfaces from the point of view of Mori theory”, Uspehi Mat. Nauk 51 (1996) no. 4(310), p. 3-72, English transl. in Russian Math. Surveys 51 (1996), no. 4, p. 585–652 | DOI | MR | Zbl

[Kal13] A.-S. Kaloghiros - “Relations in the Sarkisov program”, Compositio Math. 149 (2013) no. 10, p. 1685-1709 | DOI | MR | Zbl

[Kaw92] Y. Kawamata - “Boundedness of -Fano threefolds”, in Proceedings of the International Conference on Algebra, Part 3 (Novosibirsk, 1989), Contemp. Math., vol. 131, American Mathematical Society, Providence, RI, 1992, p. 439-445 | MR | Zbl

[KKL16] A.-S. Kaloghiros, A. Küronya & V. Lazić - “Finite generation and geography of models”, in Minimal models and extremal rays (Kyoto, 2011), Adv. Stud. Pure Math., vol. 70, Math. Soc. Japan, Tokyo, 2016, p. 215-245 | DOI | MR | Zbl

[KM98] J. Kollár & S. Mori - Birational geometry of algebraic varieties, Cambridge Tracts in Math., vol. 134, Cambridge University Press, Cambridge, 1998 | DOI | MR | Zbl

[KMMT00] J. Kollár, Y. Miyaoka, S. Mori & H. Takagi - “Boundedness of canonical -Fano 3-folds”, Proc. Japan Acad. Ser. A Math. Sci. 76 (2000) no. 5, p. 73-77 | DOI | MR | Zbl

[Kol96] J. Kollár - Rational curves on algebraic varieties, Ergeb. Math. Grenzgeb. (3), vol. 32, Springer-Verlag, Berlin, 1996 | DOI | MR | Zbl

[Kra18] H. Kraft - “Regularization of rational group actions”, 2018 | arXiv | Zbl

[Lon16] A. Lonjou - “Non simplicité du groupe de Cremona sur tout corps”, Ann. Inst. Fourier (Grenoble) 66 (2016) no. 5, p. 2021-2046 | DOI | Numdam | MR | Zbl

[LZ17] S. Lamy & S. Zimmermann - “Signature morphisms from the Cremona group over a non-closed field”, 2017, J. Eur. Math. Soc. (JEMS) (to appear) | arXiv

[Mat58] T. Matsusaka - “Polarized varieties, fields of moduli and generalized Kummer varieties of polarized abelian varieties”, Amer. J. Math. 80 (1958), p. 45-82 | DOI | MR | Zbl

[Mat63] H. Matsumura - “On algebraic groups of birational transformations”, Atti Accad. Naz. Lincei Rend. Cl. Sci. Fis. Mat. Natur. (8) 34 (1963), p. 151-155 | MR | Zbl

[Sch19] J. Schneider - “Relations in the Cremona group over perfect fields”, 2019 | arXiv

[Sob02] I. V. Sobolev - “Birational automorphisms of a class of varieties fibered by cubic surfaces”, Izv. Ross. Akad. Nauk Ser. Mat. 66 (2002) no. 1, p. 203-224 | DOI | MR | Zbl

[UZ19] C. Urech & S. Zimmermann - “A new presentation of the plane Cremona group”, Proc. Amer. Math. Soc. 147 (2019) no. 7, p. 2741-2755 | DOI | MR | Zbl

[Wei55] A. Weil - “On algebraic groups of transformations”, Amer. J. Math. 77 (1955), p. 355-391 | DOI | MR | Zbl

[Zim18] S. Zimmermann - “The Abelianization of the real Cremona group”, Duke Math. J. 167 (2018) no. 2, p. 211-267 | DOI | MR | Zbl

Cité par Sources :