Detecting Flat Normal Cones Using Segre Classes
نویسندگان
چکیده
منابع مشابه
Detecting Flat Normal Cones Using Segre Classes
Given a flat, projective morphism Y → T from an equidimensional scheme to a nonsingular curve and a subscheme Z of Y , we give conditions under which specialization of the Segre class s(NZY ) of the normal cone of Z in Y implies flatness of the normal cone. We apply this result to study when the relative tangent star cone of a flat family is flat.
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ژورنال
عنوان ژورنال: Journal of Algebra
سال: 2001
ISSN: 0021-8693
DOI: 10.1006/jabr.2001.8946