Abstract
We formulate a conjecture characterizing smooth projective varieties in positive characteristic whose Frobenius morphism can be lifted modulo p2-we expect that such varieties, after a finite étale cover, admit a toric fibration over an ordinary abelian variety.We prove that this assertion implies a conjecture of Occhetta and Wísniewski, which states that in characteristic zero a smooth image of a projective toric variety is a toric variety. To this end we analyse the behaviour of toric varieties in families showing some generalization and specialization results. Furthermore, we prove a positive characteristic analogue of Winkelmann's theorem on varieties with trivial logarithmic tangent bundle (generalizing a result of Mehta-Srinivas), and thus obtaining an important special case of our conjecture. Finally, using deformations of rational curves we verify our conjecture for homogeneous spaces, solving a problem posed by Buch-Thomsen-Lauritzen-Mehta.
Original language | English (US) |
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Pages (from-to) | 2601-2648 |
Number of pages | 48 |
Journal | Journal of the European Mathematical Society |
Volume | 23 |
Issue number | 8 |
DOIs | |
State | Published - 2021 |
Externally published | Yes |
All Science Journal Classification (ASJC) codes
- General Mathematics
- Applied Mathematics
Keywords
- Abelian variety
- Frobenius lifting
- Toric variety
- Trivial log tangent bundl