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Add total/cototal category properties - #254

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dschepler wants to merge 8 commits into
ScriptRaccoon:mainfrom
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Add total/cototal category properties#254
dschepler wants to merge 8 commits into
ScriptRaccoon:mainfrom
dschepler:total-category

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@dschepler

@dschepler dschepler commented Jun 26, 2026

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Unknown categories decided for "total" property:
category of Z-functors

Unknown categories for "cototal" property:
category of commutative monoids
category of locally ringed spaces
category of Z-functors

@dschepler

dschepler commented Jun 27, 2026

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I have some rough ideas on some of the others: on Hausdorff spaces and semigroups, I think I should be able to use an idea similar to the one for Cat to keep control over the images of constant maps. For CMon, I think the "subdirectly irreducible" property might have to do with limiting the number of maps to it - though I'm not yet at all sure how to translate that into a contradiction. And on locally ringed spaces, I have a vague idea that I might be able to define a functor whose L(T) would have a number of maps from Spec k which grows faster than possible for any single locally ringed space.

Anyway, no rush on reviewing this - I was just working on this off and on over the past week, and wanted to get the progress so far pushed before resuming work on the quasitopos PR.

Comment thread databases/catdat/data/categories/CAlg(R).yaml
Comment thread databases/catdat/data/category-properties/cototal.yaml Outdated
Comment thread databases/catdat/data/category-properties/total.yaml Outdated
Comment thread databases/catdat/data/category-properties/total.yaml
Comment thread databases/catdat/data/category-properties/cototal.yaml
Comment thread databases/catdat/data/category-properties/total.yaml
@ScriptRaccoon

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It would be cool if we can merge this soon. The few remaining cases don't have to be dealt with at this moment.

@dschepler

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OK, what does have to be resolved before we can merge it: There are several places where references are missing or incomplete. And the current proof that total -> complete needs to be finished, or replaced with a reference if for some reason finishing off the proof that the construction does give a limit is too complex.

@ScriptRaccoon

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OK, what does have to be resolved before we can merge it: There are several places where references are missing or incomplete. And the current proof that total -> complete needs to be finished, or replaced with a reference if for some reason finishing off the proof that the construction does give a limit is too complex.

Oups I forgot that the proofs are incomplete.

@dschepler
dschepler marked this pull request as ready for review July 25, 2026 21:33
@dschepler dschepler changed the title Add total/cototal category properties (WIP) Add total/cototal category properties Jul 25, 2026
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