Hostname: page-component-77c89778f8-gq7q9 Total loading time: 0 Render date: 2024-07-16T23:51:53.671Z Has data issue: false hasContentIssue false

Deformations of reductive group actions

Published online by Cambridge University Press:  24 October 2008

Gerd Müller
Affiliation:
Fachbereich Mathematik, Universität Mainz, Saarstraβe 21, D-6500 Mainz, West Germany

Extract

Consider actions of a reductive complex Lie group G on an analytic space germ (X, 0). In a previous paper [16] we proved that such an action is determined uniquely (up to conjugation with an automorphism of (X, 0)) by the induced action of G on the tangent space of (X, 0). Here it will be shown that every deformation of such an action, parametrized holomorphically by a reduced analytic space germ, is trivial, i.e. can be obtained from the given action by conjugation with a family of automorphisms of (X, 0) depending holomorphically on the parameter. (For a more precise formulation in terms of actions on analytic ℂ-algebras, see Theorem 2 below. An analogue for actions on formal ℂ-algebras is given there too.)

Type
Research Article
Copyright
Copyright © Cambridge Philosophical Society 1989

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

[1]Bierstone, E. and Milman, P.. Invariant solutions of analytic equations. Enseign. Math. (2) 25 (1979), 115130.Google Scholar
[2]Bourbaki, N.. Éléments de mathématique. Livre VI, Intégration, Chapitres 1, 2, 3 et 4. Actualités Scientifiques et Industrielles vol. 1175 (Hermann, 1965).Google Scholar
[3]Bungart, L.. Holomorphic functions with values in locally convex spaces and applications to integral formulas. Trans. Amer. Math. Soc. 111 (1964), 317344.CrossRefGoogle Scholar
[4]Forster, O.. Funktionswerte als Randintegrale in komplexen Räumen. Math. Ann. 150 (1963), 317324.CrossRefGoogle Scholar
[5]Galligo, A.. Théorème de division et stabilité en géométrie analytique locale. Ann. Inst. Fourier (Grenoble) 29 2 (1979), 107184.CrossRefGoogle Scholar
[6]Grauert, H. and Remmert, R.. Komplexe Räume. Math. Ann. 136 (1958), 245318.CrossRefGoogle Scholar
[7]Grauert, H. and Remmert, R.. Analytische Stellenalgebren. Grundlehren math. Wissenschaften vol. 176 (Springer-Verlag, 1971).CrossRefGoogle Scholar
[8]Hauser, H. and Müller, G.. Algebraic singularities have maximal reductive automorphism groups. Nagoya Math. J. 113 (1989), 181186.CrossRefGoogle Scholar
[9]Hochschild, G. P.. Basic theory of algebraic groups and Lie algebras. Graduate Texts in Math. vol. 75 (Springer-Verlag, 1981).CrossRefGoogle Scholar
[10]Hochschild, G. and Mostow, G. D.. Representations and representative functions of Lie groups, III. Ann. of Math. (2) 70 (1959), 85100.CrossRefGoogle Scholar
[11]Humphreys, J. E.. Linear algebraic groups. Graduate Texts in Math. vol. 21 (Springer-Verlag, 1975).CrossRefGoogle Scholar
[12]Jurchescu, M.. On the canonical topology of an analytic algebra and of an analytic module. Bull. Soc. Math. France 93 (1965), 129153.CrossRefGoogle Scholar
[13]Kaup, W.. Reelle Transformationsgruppen und invariante Metriken auf komplexen Räumen. Invent. Math. 3 (1967), 4370.CrossRefGoogle Scholar
[14]Kaup, W.. Einige Bemerkungen über Automorphismengruppen von Stellenringen. Bayer. Akad. Wiss. Math.-Natur. Kl. Sitzungsber. 1967 (1968), 4350.Google Scholar
[15]Koras, M.. Deformations of actions of linearly reductive groups. Ann. Soc. Math. Polon. Ser. I Comment. Math. 22 (1980), 8183.Google Scholar
[16]Müller, G.. Reduktive Automorphismengruppen analytischer ℂ-Algebren. J. Heine Angew. Math. 364 (1986), 2634.Google Scholar
[17]Müller, G.. Actions of complex Lie groups on analytic ℂ-algebras. Monatsh. Math. 103 (1987), 221231.CrossRefGoogle Scholar
[18]Müller, G.. Remarks on iteration of formal automorphisms. Aequationes Math. 35 (1988), 1722.CrossRefGoogle Scholar
[19]Richardson, R. W.. Deformations of Lie subgroups and the variation of isotropy subgroups. Ada Math. 129 (1972), 3573.Google Scholar