Coverings of curves and non-existence of certain models of them in the quadric surface
نویسنده
چکیده
Let C ⊂ S := P1×P1 be an integral curve and ν : X → C its normalization. Set L := ν∗(OS(1, 0)). Here we give numerical conditions which imply that the pair (X,L) is not the pull-back of a pair (Y,R) with Y a smooth curve of genus q > 0 andR ∈ Pic(Y ). Mathematics Subject Classification: 14H50; 14H51
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