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NumericalGodeaux :: precomputedTorsZ4Line

precomputedTorsZ4Line -- compute a line leading generically to a Z/4-Godeaux surface using a unirational parametrization

Synopsis

Description

The locus of lines in Q leading generically to ℤ/4-numerical Godeaux surfaces (with two fixed double base points of the bicanonical system) is birational to a union 3  times  ℙ1. The procedures gives two parametrization homomorphisms from Sa to the coordinate ring of a 3  × ℙ1, where the image of each map gives a point in Q whose connecting line is completely contained in Q and leads generically to a ℤ/4-Godeaux surface.

Ways to use precomputedTorsZ4Line :