Sheaves for predicative toposes

Benno van den Berg

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Sheaves for predicative toposes

Benno van den Berg

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Abstract

In this paper, we identify some categorical structures in which one can model predicative formal systems: in other words, predicative analogues of the notion of a topos, with the aim of using sheaf models to interprete predicative formal systems. Among our technical results, we prove that all the notions of a ``predicative topos'' that we consider, are stable under presheaves, while most are stable under sheaves.

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Benno van den Berg. 2005-07-22. Sheaves for predicative toposes. https://arxiv.org/abs/math/0507480

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