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Timeline for Small objects in categories

Current License: CC BY-SA 3.0

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Jan 4, 2014 at 13:02 vote accept Marci
Jan 3, 2014 at 23:54 comment added Qiaochu Yuan "Point" can also mean "monoidal unit for some natural monoidal structure" (not necessarily the product or coproduct, as in the case of the terminal or initial object respectively).
Jan 3, 2014 at 20:54 comment added Dylan Wilson I think the fact that we had the initial/final object was incidental. That a point is a compact generator is what we're after. In the category of chain complexes of $R$-modules you'd start with $R$; closing under finite homotopy colimits would give finite complexes of free modules. Again, idempotent completing gives perfect complexes.
Jan 3, 2014 at 20:44 comment added Marci Thank you! My only problem is the following. Point in a general category should be either the initial object or the terminal object. In the category of $R$-mod or in the category of (co)chain complexes, however, it is the trivial object (0), and any colimit of that is the trivial object, so I won't get any interesting objects.
Jan 3, 2014 at 20:31 history answered Dylan Wilson CC BY-SA 3.0