Seifert $G_m$-bundles

Abstract

A Seifert bundle over a variety X is a variety Y with a proper action of the multiplicative group such that the quotient is X. The topological version of this notion (using circle actions) was introduced by Seifert, the holomorphic version by Orlik and Wagreich. The aim of this paper is to provide the foundational results for Seifert bundles over an arbitrary normal variety X. The main results are a classification and a smoothness criterion.

revision: references to 5 papers added, no other changes

References in corpus (1)

• Einstein Metrics on Spheres

Cited by in corpus (5)

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