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Stream: learning: questions

Topic: Naming Natural Transformations


view this post on Zulip Ruby Khondaker (she/her) (Feb 26 2026 at 10:18):

Bit of a silly question, but do people have preferred naming conventions for natural transformations? If I'm working with lots of universal properties it helps to give readable names to the isomorphisms witnessing representability, and just using greek letters like η\eta isn't the most helpful. Of course you can always go with \cong but that suppresses which isomorphism you're referring to, instead just saying that there exists one.

As an example, I've seen a few authors call the natural isomorphism between homsets for an adjunction a "transpose", which works alright when you have a single adjunction.

view this post on Zulip David Michael Roberts (Feb 26 2026 at 10:22):

I sometimes use letters from the front of the alphabet (Latin or Greek), so: a, b, \alpha, \beta : F => G, for functors F,G (and H, K), if generic functors.