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On Complex Homogeneous Spaces with Top Homology in Codimension Two

Published online by Cambridge University Press:  20 November 2018

D. N. Akhiezer
Affiliation:
B. Spasskaya ul. 33, kv. 33 129010 Moscow Russia, e-mail: [email protected]
B. Gilligan
Affiliation:
Department of Mathematics and Statistics University of Regina Regina, Saskatchewan S4S 0A2, e-mail: [email protected]
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Abstract

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Define dx to be the codimension of the top nonvanishing homology group of the manifold X with coefficients in 2. We investigate homogeneous spaces X := G/H, where G is a connected complex Lie group and H is a closed complex subgroup for which dx = 1,2 and O(X) ≠ ℂ. There exists a fibration π: G/HG/U such that G/U is holomorphically separable and π*(O(G/U)) = O(G/H), see [11]. We prove the following. If dx = 1, then F := U/H is compact and connected and Y :=G/U is an affine cone with its vertex removed. If dx = 2, then either F is connected with dF = 1 and Y is an affine cone with its vertex removed, or F is compact and connected and dy = 2, where Y is ℂ, the affine quadric Q2, ℙ2Q (with Q a quadric curve) or a homogeneous holomorphic * -bundle over an affine cone minus its vertex which is itself an algebraic principal bundle or which admits a two-to-one covering that is.

Keywords

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 1994

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