Lang-Weil type bounds in finite difference fields

Basic data for this talk

Type of talkscientific Talk
Name der VortragendenHils, Martin
Date of talk11/01/2023
Talk languageEnglish

Information about the event

Name of the eventModel Theory: Combinatorics, Groups, Valued Fields and Neostability
Event period08/01/2023 - 14/01/2023
Event locationMathematisches Forschungsinstitut Oberwolfach
Event websitehttps://publications.mfo.de/handle/mfo/4040

Abstract

(joint work with Ehud Hrushovski, Jinhe Ye and Tingxiang Zou) We prove Lang-Weil type bounds for the number of rational points of difference varieties over finite difference fields, in terms of the transformal dimension of the variety and assuming the existence of a smooth rational point. It follows that in (certain) non-principle ultraproducts of finite difference fields the course dimension of a quantifier free type equals its transformal transcendence degree. The proof uses a strong form of the Lang-Weil estimates and, as key ingredient to obtain equidimensional Frobenius specializations, the recent work of Dor and Hrushovski on the non-standard Frobenius acting on an algebraically closed non-trivially valued field, in particular the pure stable embeddedness of the residue difference field in this context.
KeywordsLang-Weil type bounds; finite difference field; non-standard counting

Speakers from the University of Münster

Hils, Martin

Projects the talk is about

Duration: 01/01/2020 - 31/12/2024
Funded by: DFG - Individual Grants Programme
Type of project: Individual project
Duration: 01/01/2019 - 31/12/2025 | 1st Funding period
Funded by: DFG - Cluster of Excellence
Type of project: Subproject in DFG-joint project hosted at University of Münster