The GaussianWahl map for trigonal curves
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 by James N. Brawner PDF
 Proc. Amer. Math. Soc. 123 (1995), 13571361 Request permission
Abstract:
If a curve C is embedded in projective space by a very ample line bundle L, the Gaussian map ${\Phi _{C,L}}$ is defined as the pullback of hyperplane sections of the classical Gauss map composed with the Plücker embedding. When $L = K$, the canonical divisor of the curve C, the map is known as the GaussianWahl map for C. We determine the corank of the GaussianWahl map to be $g + 5$ for all trigonal curves (i.e., curves which admit a 3to1 mapping onto the projective line) by examining the way in which a trigonal curve is naturally embedded in a rational normal scroll.References

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Additional Information
 © Copyright 1995 American Mathematical Society
 Journal: Proc. Amer. Math. Soc. 123 (1995), 13571361
 MSC: Primary 14H60; Secondary 14N05
 DOI: https://doi.org/10.1090/S0002993919951260161X
 MathSciNet review: 1260161