Formalizing equivalences without tears

Tom de Jong

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.