2016/09/29 by Enrico Arbarello, Arbarello, Enrico, Andrea Bruno +1
Arts and Humanities · Mathematics · #Algebraic Geometry and Number Theory #Historical Studies and Socio-cultural Analysis #math.AG #msc:14H51 #msc:14J28
paper · pdf · doi:10.48550/arxiv.1609.09256
arxiv created 2016/09/29 · arxiv updated 2016/09/30
A genus-g du Val curve is a degree-3g plane curve having 8 points of multiplicity g, one point of multiplicity g-1, and no other singularity. We prove that the corank of the Gauss-Wahl map of a general du Val curve of odd genus (>11) is equal to one. This, together with the results of [1], shows that the characterisation of Brill-Noether-Petri curves with non-surjective Gauss-Wahl map as hyperplane sections of K3 surfaces and limits thereof, obtained in [3], is optimal.