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arXiv · alg-geom/9707012

Weak semistable reduction in characteristic 0

Dan Abramovich·Kalle Karu
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Abstract

Let X->B be a morphism of varieties in characteristic zero. Semistable reduction has been proved for dim(B)=1 (Kempf, Knudsen, Mumford, Saint-Donat), dim(X)=dim(B)-1 (de Jong) and dim(X)=dim(B)+2 (Alexeev, Kollar, Shepherd-Barron). In this paper we consider the general case. First we define what we mean by a semistable morphism in terms of toroidal embeddings. Then we reduce the varieties to toroidal embeddings and solve a slightly weaker version of semistable reduction. We also state the full semistable reduction problem in terms of combinatorics of the associated polyhedral complexes.

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Dan Abramovich, Kalle Karu. 1997-07-13. Weak semistable reduction in characteristic 0. https://arxiv.org/abs/alg-geom/9707012

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