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arXiv · 1905.12113

Hyperelliptic limits of quadrics through canonical curves and ribbons

Alexander Polishchuk·Eric Rains
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Abstract

We describe explicitly all hyperelliptic limits of quadrics through smooth canonical curves of genus $g$ in ${\mathbb P}^{g-1}$. Also, we construct an open embedding of the blow up of a ${\rm PGL}_g$-bundle over the moduli space of curves of genus $g$ along the hyperelliptic locus into the blow up of the canonical Hilbert scheme of ${\mathbb P}^{g-1}$ along the closure of the locus of canonical ribbons, which are certain double thickenings of rational normal curves introduced and studied by Bayer and Eisenbud.

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Alexander Polishchuk, Eric Rains. 2019-05-28. Hyperelliptic limits of quadrics through canonical curves and ribbons. https://arxiv.org/abs/1905.12113

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