On non-liftable Calabi-Yau threefolds
Algebraic Geometry
2007-05-23 v2
Abstract
Only two ways to construct non-liftable Calabi-Yau threefolds are currently known, one example by Hirokado and one method of Schr\"oer. This article computes some cohomological invariants of these examples of non-liftable Calabi-Yau threefolds, in particular it computes their mini-versal deformations. One conclusion is that their mixed characteristic mini-versal deformation spaces are actually smooth over the characteristic base field. Furthermore, a new family, constructed in the spirit of Schr\"oer, is introduced and the same calculations are performed for it.
Cite
@article{arxiv.math/0306435,
title = {On non-liftable Calabi-Yau threefolds},
author = {Torsten Ekedahl},
journal= {arXiv preprint arXiv:math/0306435},
year = {2007}
}
Comments
31 pages. An improper use of a result of Deligne and Illusie has been replaced with a proper one. Also some other minor corrections