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S21 is not a k-space #944

Closed david20000813 closed 2 days ago

david20000813 commented 5 days ago

As mentioned in issue #928, S21, the weak topology on separable Hilbert space, is not a $k$-space - more precisely, $k_1$-space (P140). Note that $k_1$, $k_2$, and $k_3$ are equivalent for Hausdorff spaces.

david20000813 commented 5 days ago

(A small remark is that, while I've checked that the DOI is correct, I'm having trouble accessing the paper, since the journal website seems to be down at the moment. I ended up using Wayback Machine to access the journal website and the paper.)

yhx-12243 commented 4 days ago

(A small remark is that, while I've checked that the DOI is correct, I'm having trouble accessing the paper, since the journal website seems to be down at the moment. I ended up using Wayback Machine to access the journal website and the paper.)

(offtopic: I can access the paper, it seems not down yet, could you please give some screenshots?) offtopic

david20000813 commented 3 days ago

@yhx-12243 It’s also working for me now. It might just happened to be down the day I checked for some reason.

StevenClontz commented 2 days ago

Available as branch PR944