UniMath / agda-unimath

The agda-unimath library
https://unimath.github.io/agda-unimath/
MIT License
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Explore what we want to call "isomorphisms" #1072

Open VojtechStep opened 6 months ago

VojtechStep commented 6 months ago

In https://github.com/UniMath/agda-unimath/pull/1056#discussion_r1519953433 @EgbertRijke raised the question whether we should keep with the type theory convention of having "isomorphisms" be in general maps with structure, or if we should reappropriate it for a well-behaved coherent concept.

For now we have the incoherent "isomorphisms in (large) (pre)categories" (invertible morphisms) and coherent "pointed isomorphisms" (biinvertible maps) are introduced in #1056.

fredrik-bakke commented 6 months ago

Hey! I'd just like to note that the notion of isomorphisms in precategories is not incoherent. Rather, it is coherent, but the definition is only coherent for set-level structures and doesn't generalize to higher structures without modifications.