Gonality for stable curves and their maps with a smooth curve as their target

Edoardo Ballico1
1Department of Mathematics, University of Trento, Povo, Italy

Tóm tắt

Here we study the deformation theory of some maps f: X → ℙ r , r = 1, 2, where X is a nodal curve and f|T is not constant for every irreducible component T of X. For r = 1 we show that the “stratification by gonality” for any subset of with fixed topological type behaves like the stratification by gonality of M g.

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Tài liệu tham khảo

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