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Timeline for Enrichments vs Internal homs

Current License: CC BY-SA 4.0

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Aug 25, 2018 at 19:49 answer added Giorgio Mossa timeline score: 3
Jun 22, 2018 at 13:35 vote accept Max Schattman
Jun 21, 2018 at 14:54 answer added Tim Campion timeline score: 5
Jun 21, 2018 at 14:50 comment added Max Schattman @Tim: Put this as an answer and I can accept it.
Jun 21, 2018 at 13:21 comment added Tim Campion Here's an example of "wrong-way" self-enrichment: the category $Cat$ of small categories is enriched in itself in the usual way since it is cartesian closed. But it also has another self-enrichment where you take the maximal subgroupoid of each hom-category. This sort of variant enrichment is important e.g. to make $Cat$ into a simplicial model category.
Jun 20, 2018 at 18:30 comment added Mike Shulman I would expect that a monoidal category $C$ could happen to be the underlying category of some $C$-enriched category in a "wrong" way so that the enriched hom-objects aren't right adjoints of the tensor product, but I don't have an example ready to hand.
Jun 20, 2018 at 18:29 comment added Mike Shulman Yes, a closed monoidal category is enriched over itself. In the symmetric case this is section 1.6 of the standard reference Basic concepts of enriched category theory tac.mta.ca/tac/reprints/articles/10/tr10abs.html. I think that usually when people say "internal homs" they are referring to a monoidal structure being closed, or more generally to a closed category structure (ncatlab.org/nlab/show/closed+category) -- it doesn't make sense to talk about enrichment over a category until it has a monoidal/closed/multi/etc structure.
Jun 20, 2018 at 15:51 history asked Max Schattman CC BY-SA 4.0