25 research outputs found

    Definable sets of Berkovich curves

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    In this article, we functorially associate definable sets to kk-analytic curves, and definable maps to analytic morphisms between them, for a large class of kk-analytic curves. Given a kk-analytic curve XX, our association allows us to have definable versions of several usual notions of Berkovich analytic geometry such as the branch emanating from a point and the residue curve at a point of type 2. We also characterize the definable subsets of the definable counterpart of XX and show that they satisfy a bijective relation with the radial subsets of XX. As an application, we recover (and slightly extend) results of Temkin concerning the radiality of the set of points with a given prescribed multiplicity with respect to a morphism of kk-analytic curves. In the case of the analytification of an algebraic curve, our construction can also be seen as an explicit version of Hrushovski and Loeser's theorem on iso-definability of curves. However, our approach can also be applied to strictly kk-affinoid curves and arbitrary morphisms between them, which are currently not in the scope of their setting.Comment: 53 pages, 1 figure. v2: Section 7.2 on weakly stable fields added and other minor changes. Final version. To appear in Journal of the Institute of Mathematics of Jussie

    Integration and Cell Decomposition in PP-minimal Structures

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    We show that the class of L\mathcal{L}-constructible functions is closed under integration for any PP-minimal expansion of a pp-adic field (K,L)(K,\mathcal{L}). This generalizes results previously known for semi-algebraic and sub-analytic structures. As part of the proof, we obtain a weak version of cell decomposition and function preparation for PP-minimal structures, a result which is independent of the existence of Skolem functions. %The result is obtained from weak versions of cell decomposition and function preparation which we prove for general PP-minimal structures. A direct corollary is that Denef's results on the rationality of Poincar\'e series hold in any PP-minimal expansion of a pp-adic field (K,L)(K,\mathcal{L}).Comment: 22 page

    An example of a PP-minimal structure without definable Skolem functions

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    We show there are intermediate PP-minimal structures between the semi-algebraic and sub-analytic languages which do not have definable Skolem functions. As a consequence, by a result of Mourgues, this shows there are PP-minimal structures which do not admit classical cell decomposition.Comment: 9 pages, (added missing grant acknowledgement
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