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(I'm one of Jeff's housemates.) Going to the grocery would violate our rules even if you could stay 6ft away, because it's inside.

I guess there's one market in our area that's (a) outside, with (b) careful distancing. Going there would be fine I think, but I don't know if any of us have.

There wasn't much but I'm working on resurrecting what there was. Maybe I'll get DNS fixed this weekend but for now: http://www.davidchudzicki.com.s3-website-us-east-1.amazonaws.com/

To add to the confusion, there are normally only two symbols for infinity to go around - ω and ∞

This post is the first I recall seeing ω used to refer to a cardinal. (The smallest infinite cardinal is usually called א‎₀.)

And I think hyperreals are probably a much less common topic than the other three, so at least we have different notation for the top three of these four notions (ω for the ordinal, א‎₀ for the cardinal, ∞ for the limit).

I'm not confident in this, but also: It looks to me like ω can be considered the same number in the ordinals, surreals, and hyperreals (since the surreals contain both of the other two). So I guess that's probably why we use the same notation, and why it's not really a serious ambiguity.