The Tate-Oort Group Scheme \(\mathbb{TO}_p\)
- Authors: Reid M.1
-
Affiliations:
- Mathematics Institute
- Issue: Vol 307, No 1 (2019)
- Pages: 245-266
- Section: Article
- URL: https://journals.rcsi.science/0081-5438/article/view/175956
- DOI: https://doi.org/10.1134/S0081543819060154
- ID: 175956
Cite item
Abstract
Over an algebraically closed field of characteristic p, there are three group schemes of order p, namely the ordinary cyclic group ℤ/p, the multiplicative group \(\mu_{p}\subset\mathbb{G}_{m}\), and the additive group αp ⊂ \(\mathbb{G}_{a}\). The Tate-Oort group scheme \(\mathbb{TO}_p\) puts these into one happy family, together with the cyclic group of order p in characteristic zero. This paper studies a simplified form of \(\mathbb{TO}_p\), focusing on its representation theory and basic applications in geometry. A final section describes more substantial applications to varieties having p-torsion in Picτ, notably the 5-torsion Godeaux surfaces and Calabi-Yau threefolds obtained from \(\mathbb{TO}_5\)-invariant quintics.
About the authors
Miles Reid
Mathematics Institute
Author for correspondence.
Email: Miles.Reid@warwick.ac.uk
United Kingdom, Coventry, CV4 7AL
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