Metric groups attached to biextensions
نویسنده
چکیده
Let G be a connected, unipotent, perfect group scheme over an algebraically closed field of characteristic p > 0 and let E be a biextension (cf. [SGA7tI], exp. VII, no. 1) of G ×k G by the discrete group Qp/Zp. When E is skewsymmetric (cf. sec. 3.1), V. Drinfeld defined in [Dr] a certain metric group A (cf. appendix) associated to E. In this article, we prove a conjecture stated in [Dr] (cf. sec. 3.2, Theorem 1) about the class of the metric group A in the Witt group (cf. appendix).
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تاریخ انتشار 2008