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arXiv · 2603.09510

Fodor space in generalized descriptive set theory

Ido Feldman·Miguel Moreno
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Abstract

We study the continuous reducibility of isomorphism relations in the space of regresive functions in $κ^κ$. We show for inaccessible $κ$, that if $\mathcal{T}$ is a theory with less than $κ$ non-isomorphic models of size $κ$ and $\mathcal T'$ is unstable or superstable non-classifiable, then the isomorphism of models of $\mathcal{T}$ is continuous reducible to the isomorphism of models of $\mathcal{T}'$.

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Ido Feldman, Miguel Moreno. 2026-05-23. Fodor space in generalized descriptive set theory. https://arxiv.org/abs/2603.09510

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