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arXiv · 2408.11501

Formalizing equivalences without tears

Tom de Jong
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Abstract

This expository note describes two convenient techniques in the context of homotopy type theory for proving and formalizing that a given map is an equivalence. The first technique decomposes the map as a series of basic equivalences, while the second refines this approach using the 3-for-2 property of equivalences. The techniques are illustrated by proving a basic result in synthetic homotopy theory.

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Tom de Jong. 2025-04-23. Formalizing equivalences without tears. https://doi.org/10.4230/lipics.types.2024.1

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