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3-fold divisorial extremal neighborhoods over cE7 and cE6 Compound DuVal singularities

Nikolaos Tziolas
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Abstract

Let X be the germ of a Gorenstein 3-fold singularity and C a smooth curve through it such that the general hyperplane section S of X containing D is DuVal of type E6 or E7. In this paper we obtain criteria for the existence of a terminal divisorial extremal neighborhood f: Y-->X contracting an irreducible divisor E onto C and classify all such neighborhoods.

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Nikolaos Tziolas. 2008-01-17. 3-fold divisorial extremal neighborhoods over cE7 and cE6 Compound DuVal singularities. https://arxiv.org/abs/math/0703855

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