Hodge sheaves underlying flat projective families

Sándor J. Kovács; Behrouz Taji

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arXiv · 2103.03515

Hodge sheaves underlying flat projective families

Sándor J. Kovács·Behrouz Taji

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Abstract

We show that, for any fixed weight, there is a natural system of Hodge sheaves, whose Higgs field has no poles, arising from a flat projective family of varieties parametrized by a regular complex base scheme, extending the analogous classical result for smooth projective families due to Griffiths. As an application, based on positivity of direct image sheaves, we establish a criterion for base spaces of rational Gorenstein families to be of general type. A key component of our arguments is centered around the construction of derived categorical objects generalizing relative logarithmic forms for smooth maps and their functorial properties.

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BibTeX RIS

Sándor J. Kovács, Behrouz Taji. 2021-03-05. Hodge sheaves underlying flat projective families. https://arxiv.org/abs/2103.03515

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