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cotangentSheaf(ProjectiveVariety) -- cotangent sheaf of a projective variety

Synopsis

Description

This function computes the cotangent sheaf of the projective variety X.

As an example we verify Gauss-Bonnet's theorem on a plane quartic curve:

X=Proj(QQ[x,y,z]/(x^4+y^4+z^4))
genus(X)
omega = cotangentSheaf(X)
degree omega

See also