The Picard group of a K3 surface and its reduction modulo p
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چکیده
We present a method to compute the geometric Picard rank of a K3 surface over Q. Contrary to a widely held belief, we show it is possible to verify Picard rank 1 using reduction only at a single prime. Our method is based on deformation theory for invertible sheaves.
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تاریخ انتشار 2010