Abstract
Let X = Spec A be a normal affine variety over an algebraically closed field k of characteristic 0 endowed with an effective action of a torus \( \mathbb{T} \) of dimension n. Let also ∂ be a homogeneous locally nilpotent derivation on the normal affine \( {\mathbb{Z}^n} \)-graded domain A, so that ∂ generates a k +-action on X that is normalized by the \( \mathbb{T} \)-action.
We provide a complete classiffication of pairs (X, ∂) in two cases: for toric varieties (n = dim X) and in the case where n = dim X − 1. This generalizes previously known results for surfaces due to Flenner and Zaidenberg. As an application we compute the homogeneous Makar-Limanov invariant of such varieties. In particular, we exhibit a family of nonrational varieties with trivial Makar-Limanov invariant.
Similar content being viewed by others
References
K. Altmann, J. Hausen, Polyhedral divisors and algebraic torus actions, Math. Ann. 334 (2006), 557–607.
K. Altmann, J. Hausen, H. Süß, Gluing affine torus actions via divisorial fans, Transform. Groups 13 (2008), 215–242.
N. Bourbaki, Éléments de mathématiques. Algébre. Chapitres 4 à 7, Lecture Notes in Mathematics, Vol. 864, Masson, Paris, 1981.
D. Daigle, G. Freudenburg, A counterexample to Hilbert’s Fourteenth Problem in dimension five, J. Algebra 221 (1999), 528–535.
M. Demazure, Sous-groupes algébriques de rang maximum du groupe de Cremona, Ann. Sci. École Norm. Sup. (4) 3 (1970), 507–588.
H. Flenner, M. Zaidenberg, Normal affine surfaces with \( {\mathbb{C}^*} \) -actions, Osaka J. Math. 40 (2003), 981–1009.
H. Flenner, M. Zaidenberg, Locally nilpotent derivations on affine surfaces with a \( {\mathbb{C}^*} \) -action, Osaka J. Math. 42 (2005), 931–974.
G. Freudenburg, A counterexample to Hilbert’s fourteenth problem in dimension six, Transform. Groups 5 (2000), 61–71.
G. Freudenburg, Algebraic Theory of Locally Nilpotent Derivations, Encyclopaedia of Mathematical Sciences, Vol. 136, Invariant Theory and Algebraic Transformation Groups, Vol. 7, Springer, Berlin, 2006.
R. Hartshorne, Algebraic geometry, Graduate Texts in Mathematics, Vol. 52, Springer-Verlag, New York, 1977. Russian transl.: Р. Хартсхорн, Алгебраи-ческая геометрия, Мир, М, 1981.
T. Kambayashi, P. Russell, On linearizing algebraic torus actions, J. Pure Appl. Algebra 23 (1982), 243–250.
L. Kaup, K-H. Fieseler, Hyperbolic \( {\mathbb{C}^*} \) -actions on affine algebraic surfaces, in: Complex Analysis, Proc. Int. Workshop Ded. H. Grauert, Wuppertal, 1991, Aspects Math., Vol. E 17, Vieweg, Braunschweig, 1991, pp. 160–168.
G. Kempf, F. Knudson, D. Mumford, B. Saint-Donat, Toroidal Embeddings I, Lecture Notes in Mathematics, Vol. 339, Springer-Verlag, New York, 1973.
S. Kuroda, A condition for finite generation of the kernel of a derivation, J. Algebra 262, (2003), 391–400.
A. Liendo, \( {\mathbb{G}_a} \) -actions of fiber type on affine \( \mathbb{T} \) -varieties, arXiv:0911.1110v1 [math.AG] (2009), 12 pp.
A. Liendo, Rational singularities of normal \( \mathbb{T} \) -varieties, arXiv:0909.4134v1 [math.AG] (2009), 12 pp.
L. Makar-Limanov, Locally nilpotent derivations, a new ring invariant and applications, 60 pp., available at: http://www.math.wayne.edu/∼lml/.
T. Oda, Convex Bodies and Algebraic Geometry. An Introduction to the Theory of Toric Varieties, Ergebnisse der Mathematik und ihrer Grenzgebiete, 3, Folge, Bd. 15, Springer-Verlag, Berlin, 1985.
V. L. Popov, On the Makar-Limanov, Derksen invariants, and finite automorphism groups of algebraic varieties, arXiv:1001.1311v2 [math.AG](2010), 22 pp.
P. Roberts, An infinitely generated symbolic blow-up in a power series ring and a new counterexample to Hilbert’s fourteenth problem, J. Algebra 132 (1990), 461–473.
H. Süß, Canonical divisors on \( \mathbb{T} \) -varieties, arXiv:0811.0626v1[math.AG](2008), 22 pp.
Д. А. Тимашев, Классификация G-многообразий сложности 1, Изв. РАН, сер. мат. 61(2) (1997), 127–162. Engl. transl.: D. A. Timashev, Classiffication of G-varieties of complexity 1, Izv. Math. 61(2) (1997), 363–397.
D. Timashev, Torus actions of complexity one, in: Toric Topology, Osaka, Japan, May 28–June 3, 2006, Contemp. Math., Vol. 460, Amer. Math. Soc., Providence, RI, 2008, pp. 349–364.
R. Vollmert, Toroidal embeddings and polyhedral divisors, arXiv:0707.0917v1 [math.AG] (2007), 5 pp.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Liendo, A. Affine \( \mathbb{T} \)-varieties of complexity one and locally nilpotent derivations. Transformation Groups 15, 389–425 (2010). https://doi.org/10.1007/s00031-010-9089-2
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00031-010-9089-2