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arXiv · 2608.25688

A counterexample to Kanalas' problem of continuously realising types

Morgan Rogers·Joshua Wrigley
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Abstract

We give an example of a coherent theory, a topological space, and a continuous assignment of the (model-theoretic) types of the theory to the points of the space, such that there is no sheaf model of the theory over the space with the property that the fibre over a point, as a set-based model, realises the corresponding type; thus, we answer in the negative a problem posed by Krist\'of Kanalas.

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Morgan Rogers, Joshua Wrigley. 2026-08-26. A counterexample to Kanalas' problem of continuously realising types. https://arxiv.org/abs/2608.25688

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