Ample Weil Divisors on K 3 Surfaces with Du Val Singularities Valery Alexeev
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چکیده
0.3. For the singular Q-Fanos one can try to use the same approach. The first difference is that, if X has a non-Gorenstein singularity, then locally in a neighborhood of such a point a general element of I-Kxl should have Du Val singularity. The second observation is that -Kx, restricted on S, is not a Cartier divisor any more but only a Weil divisor such that its multiple is an ample Cartier divisor. Therefore, we see that in order to work with the singular case we have to consider a K3 surface with Du Val singularities and an ample Weil divisor on it.
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تاریخ انتشار 1991