Structure of geometrically non-reduced varieties
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- by Lena Ji and Joe Waldron PDF
- Trans. Amer. Math. Soc. 374 (2021), 8333-8363 Request permission
Abstract:
We prove a structural result for geometrically non-reduced varieties and give applications to Fano varieties. For example, we show that if $X$ is the generic fibre of a Mori fibre space of relative dimension $n$, and the characteristic is $p>2n+1$, then any geometric non-reducedness of $X$ comes from the base of some fibration.References
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Additional Information
- Lena Ji
- Affiliation: Department of Mathematics, Princeton University, Fine Hall, Washington Road, Princeton, New Jersey 08544
- MR Author ID: 1300809
- ORCID: 0000-0001-9854-904X
- Email: lji@math.princeton.edu
- Joe Waldron
- Affiliation: Department of Mathematics, Michigan State University, 619 Red Cedar Road, East Lansing, Michigan 48824
- MR Author ID: 1213375
- Email: waldro51@msu.edu
- Received by editor(s): March 3, 2020
- Received by editor(s) in revised form: November 13, 2020, and December 30, 2020
- Published electronically: August 25, 2021
- Additional Notes: This material is based upon work of the first author while supported by the National Science Foundation Graduate Research Fellowship Program under Grant No. DGE-1656466; and of the second author while supported by the National Science Foundation under Grant No. 1440140, while he was in residence at the Mathematical Sciences Research Institute in Berkeley, California, during the Spring of 2019. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Science Foundation.
- © Copyright 2021 American Mathematical Society
- Journal: Trans. Amer. Math. Soc. 374 (2021), 8333-8363
- MSC (2020): Primary 14D06
- DOI: https://doi.org/10.1090/tran/8388
- MathSciNet review: 4337916