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arXiv · alg-geom/9512014

Degenerations of elliptic curves and cusp singularities

Jan Stevens
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Abstract

We give more or less explicit equations for all two-dimensional cusp singularities of embedding dimension at least 4. They are closely related to Felix Klein's equations for universal curves with level n structure. The main technical result is a description of the versal deformation of an n-gon in $P^{n-1}$. The final section contains the equations for smoothings of simple elliptic singularities (of multiplicity at most 9).

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Jan Stevens. 1995-12-21. Degenerations of elliptic curves and cusp singularities. https://arxiv.org/abs/alg-geom/9512014

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