Foliations and rational connectedness in positive characteristic
نویسندگان
چکیده
منابع مشابه
Foliations and Rational Connectedness in Positive Characteristic
In this paper, the technique of foliations in characteristic p is used to investigate the difference between rational connectedness and separable rational connectedness in positive characteristic. The notion of being freely rationally connected is defined; a variety is freely rationally connected if a general pair of points can be connected by a free rational curve. It is proved that a freely r...
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The notion of a characteristic fibration is introduced. This fibration consists of a base space M and a set of fibres which are dimension groups associated to a noncommutative ring R. Every dimension group of the fibration is isomorphic to the first Betti group of M with a ‘positive cone’ depending continuously on the fibre. The characteristic fibrations are linked to the codimension–1 regular ...
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ژورنال
عنوان ژورنال: Journal of Algebraic Geometry
سال: 2010
ISSN: 1056-3911,1534-7486
DOI: 10.1090/s1056-3911-10-00552-7