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arXiv · 2502.04301

Type II Degenerations of K3 Surfaces of Degree 4

James Matthew Jones
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Abstract

We study Type II degenerations of K3 surfaces of degree 4 where the central fiber consists of two rational components glued along an elliptic curve. Such degenerations are called Tyurin degenerations. We construct explicit Tyurin degenerations corresponding to each of the 1-dimensional boundary components of the Baily-Borel compactification of the moduli space of K3 surfaces of degree 4. For every such boundary component we also construct an 18-dimensional family of Tyurin degenerations of K3 surfaces of degree 4 and compute the stable models of these degenerations.

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James Matthew Jones. 2025-02-26. Type II Degenerations of K3 Surfaces of Degree 4. https://arxiv.org/abs/2502.04301

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