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Special ramification loci on the double product of a general curve

Caterina Cumino·Eduardo Esteves·Letterio Gatto
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Abstract

Let C be a general connected, smooth, projective curve of positive genus g. For each nonnegative integer i we give formulas for the number of pairs (P,Q) em C x C off the diagonal such that (g+i-1)Q-(i+1)P is linearly equivalent to an effective divisor, and the number of pairs (P,Q) em C x C off the diagonal such that (g+i+1)Q-(i+1)P is linearly equivalent to a moving effective divisor.

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Caterina Cumino, Eduardo Esteves, Letterio Gatto. 2007-01-24. Special ramification loci on the double product of a general curve. https://arxiv.org/abs/math/0701662

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