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Talk:Kan extension

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Summary

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I think the summary is by far not informative enough. IMHO, a reader acquitted with category theory should get a better view than "all concepts are Kahn extensions".

In general, most articles about CT are too cryptic.

Names

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Pardon the bike-shedding, but IIUC, using ε and η for (resp.) the left and right Kan extensions' natural transformations makes them reversed when considering adjunctions as Kan extensions. IOW, since η is the name of the unit, going from 1 to GF, it should be the name used for the *left* Kan extension, not the right one, no? Luke Maurer (talk) 01:58, 22 April 2016 (UTC)[reply]

I agree (6 years later) and changed it. SemperVinco (talk) 01:31, 27 February 2022 (UTC)[reply]


Kan extensions as (co)limits

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I think it would be much better if one could write down how morphisms are handled by the functor. It is an essential part of a functorial assignment. — Preceding unsigned comment added by 188.109.93.69 (talk) 13:35, 6 November 2016 (UTC)[reply]