Spherical Stein spaces

D. Akhiezer; P. Heinzner

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Spherical Stein spaces

D. Akhiezer·P. Heinzner

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Abstract

Let X be an irreducible reduced complex space on which a connected compact Lie group K acts by holomorphic automorphisms. Let G be the complexification of K and g the Lie algebra of G. Following the theory of algebraic transformation groups, we call the complex space X spherical if X is normal and its tangent space at some point is generated by the vector fields from a Borel subalgebra b or g. We give several characterizations of spherical Stein spaces. In particular, we prove that a connected Stein manifold X is spherical if and only if the algebra of K-invariant differential operators on X is commutative.

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BibTeX RIS

D. Akhiezer, P. Heinzner. 2004-12-28. Spherical Stein spaces. https://arxiv.org/abs/math/0412509

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