Local Cohomologies of Isolated Non F -rational Singularities
نویسنده
چکیده
In this paper, we consider positively graded isolated non F -rational singularities (R, m) with d = dimR over the field K of positive characteristic. We give a representation of lower local cohomologies H m (R) (i < d) in terms of tight closure and limit closure of certain type of parameters. As an application to isolated singularities, we show a relation between non-vanishing of the tight closure of zero in the highest local cohomology (0)∗ H m (R) and non-vanishing of the cohomology H m (R). MSC Primary: 13A35, 13D45, Secondary: 13A02
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تاریخ انتشار 2006