Add property: ℵ₁-filtered colimits#179
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@ykawase5048 Can you perhaps help here? |
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the theorem states that every locally finite, essentially countable and cauchy complete category is ℵ₁-accessible
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This PR adds two properties:
As for ℵ₁-filtered, all categories have been decided.
To decide ℵ₁-filtered colimits for various categories, and also decide ℵ₁-accessibility for several categories (which is still open for many categories), the following theorem has been added and proven (which is very similar to other results, see its proof for details):
In particular, ℵ₁-filtered colimits exist in that case.
For the following categories, ℵ₁-filtered colimits have not been decided yet.
This PR also adds a proof that BN is ℵ₁-accessible.