Quasi-F-splitting and the Achinger–Zdanowicz Construction
Speaker(s): Fuetaro Yobuko (Tokyo University of Science)
Time: 15:00-16:15 December 4, 2025
Venue: Room 77201, Jingchunyuan 78, BICMR
Abstract: Quasi-F-splitting is a property of schemes in positive characteristic p, generalizing F-splitting. A remarkable property of quasi-F-split schemes is that they can be lifted modulo p^2. In fact, Achinger and Zdanowicz constructed such a lifting from the data of the splitting. In the case of F-split(=ordinary) abelian varieties or K3 surfaces, the resulting lifting agrees with the canonical lifting arising from Serre–Tate theory. In this talk, I will present a deformation-theoretic viewpoint on the Achinger–Zdanowicz construction.
