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arXiv · 2504.10759

Elliptic and K3 fibrations on double octic Calabi-Yau threefolds

Sławomir Cynk·Beata Kocel-Cynk
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Abstract

We study fibrations by elliptic curves and K3 surfaces of double octic Calabi-Yau threefolds determined by singular lines and points of multiplicity at least 4 of the defining octic arrangement. As a consequence we conclude that every double octic admits many elliptic and K3 fibrations. We apply descriptions of some K3 fibrations to construct a birational map between elements of two families of double octics.

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Sławomir Cynk, Beata Kocel-Cynk. 2025-04-14. Elliptic and K3 fibrations on double octic Calabi-Yau threefolds. https://arxiv.org/abs/2504.10759

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