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arXiv · 2002.09282

Homotopy Type Theory in Isabelle

Joshua Chen
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Abstract

This paper introduces Isabelle/HoTT, the first development of homotopy type theory in the Isabelle proof assistant. Building on earlier work by Paulson, I use Isabelle's existing logical framework infrastructure to implement essential automation, such as type checking and term elaboration, that is usually handled on the source code level of dependently typed systems. I also integrate the propositions-as-types paradigm with the declarative Isar proof language, providing an alternative to the tactic-based proofs of Coq and the proof terms of Agda. The infrastructure developed is then used to formalize foundational results from the Homotopy Type Theory book.

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Joshua Chen. 2020-02-14. Homotopy Type Theory in Isabelle. https://arxiv.org/abs/2002.09282

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