while (a=b()) ... infinite sets digression
Chad Netzer
chad at vision.arc.nasa.gov
Wed May 19 17:40:10 EDT 1999
Gordon McMillan wrote:
Flame-bait, which I refuse to take, and the following statement.
> > In fact, both are probably Aleph-1 sets which
> > means they are larger than the set of integers... I'm out of my
> > area, here, so I'll let it go at that. ;)
>
> Ay yi yi. They are countable (Aleph-0). Proof: you can sort
> them. In fact, using an insertion sort, I can sort them a
> _whole_lot_faster_ than you can create them. (See what happens when
> you compare infinities?).
I'm sorry I didn't use formal definitions from the start of this thread; it
would have caused less confusion. In response to the above, and as I said in
my last post, the set of all infinite length strings (with a finite alphabet) is
size aleph-1; they cannot be counted (or even sorted completely). Cantor
proved this and I won't waste your time proving it here (although it is a
short and wonderful proof). My example was in reference to this set (plus
all finite length strings). So if I expressed things in a way that caused
confusion, especially to "Mr. Set Theory" McMillan, I apologize.
> thank-god-it-doesn't-take-set-theory-to-launch-a-shuttle-ly y'rs
uhhh, yeah.
Chad Netzer
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