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Behavior of the Torsion of the Differential Module of an Algebroid Curve under Quadratic Transformations

Robert W. Berger
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Abstract

We study the difference between the lengths of the torsion of the differential modules of the local ring R of an algebroid curve and its first quadratic transform. The conjecture is that this difference should be positive if R is not regular. This is shown to be true in some cases, especially for stable complete intersections and for semigroup rings which are complete intersections.

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Robert W. Berger. 1998-05-08. Behavior of the Torsion of the Differential Module of an Algebroid Curve under Quadratic Transformations. https://arxiv.org/abs/math/9805044

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