Canonical Coordinates in Toric Degenerations

Helge Ruddat; Bernd Siebert

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arXiv · 1409.4750

Canonical Coordinates in Toric Degenerations

Helge Ruddat·Bernd Siebert

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Abstract

We prove that the mirror map is trivial for the canonical formal families of Calabi-Yau varieties constructed by Gross and the second author. In other words, the natural coordinate in a canonical Calabi-Yau family is a canonical coordinate in the sense of Hodge theory. This implies that the higher weight periods directly carry enumerative information with no further gauging necessary as opposed to the classical case. A side result is that the canonical formal families lift to analytic families. We compute the relevant period integrals explicitly. The cycles to integrate over are constructed from tropical 1-cycles in the intersection complex of the degenerate Calabi-Yau.

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Helge Ruddat, Bernd Siebert. 2014-09-16. Canonical Coordinates in Toric Degenerations. https://arxiv.org/abs/1409.4750

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