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arXiv · 2004.05592

Remarks around the non-existence of difference-closure

Zoé Chatzidakis
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Abstract

This paper shows that in general, difference fields do not have a difference closure. However, we introduce a stronger notion of closure (kappa-closure), and show that every algebraically closed difference field K of characteristic 0, with fixed field satisfying a certain natural condition, has a closure, and this closure is unique up to isomorphism over K.

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Zoé Chatzidakis. 2020-04-12. Remarks around the non-existence of difference-closure. https://doi.org/10.2140/mt.2023.2.405

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