Add hereditary metaproperty for almost all properties which are#1674
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felixpernegger wants to merge 1 commit intomainfrom
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Add hereditary metaproperty for almost all properties which are#1674felixpernegger wants to merge 1 commit intomainfrom
felixpernegger wants to merge 1 commit intomainfrom
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That may take a while to review properly. Any chance you could have a few smaller batches? |
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I kind of prefer not to. Again, most of these are trivial (think: Hereditarily separable is hereditary) |
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The example 2.5 in zbMATH 1458.54023 shows that P120 is not hereditary. If it was then it would actually be implied by P154. |
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thank you!! |
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Continuation of #1665.
I went over all properties (on spreadsheet) and noted which ones are hereditary and which ones are not.
The only ones remaining for which I do not know if they are hereditary or not are:
P120 (probably not, but hard to think of counterexample)not hereditary. See commentsP166 (likely no, because separable isnt hereditary)this is hereditary, following https://topology.pi-base.org/spaces?q=metrizable+%2B+Separable+%2B+%7EHereditarily+separable (havent added this in the pr yet)P173 (most likely no, since sequential isnt, but that was already annoying to find counterexample on the internet)not hereditary.If anyone wants to try, I used all easy tricks (locally 1-euclidean, ebeddable in R, empty space, singleton) already. A great amount of counterexamples for hard properties came from S108 and its subspaces in pi-base, maybe this also works for some of the remaing properties here.
Knowing that a property is NOT hereditary will be useful for a later proper implementation.
I was rather careful, but any metaproperty (positively) added in this PR should be checked (proofs should be all easy).
Again, the code itself was added by Claude Code based on my spreadsheet. :)