2026/01/15

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2026-01-16 00:40:20 +0100 <int-e> nothing beyond omega arises in this fashion
2026-01-16 00:40:09 +0100 <int-e> omega arises naturally as the least upper bound of all natural numbers, corresponding to having computations of arbitrary length
2026-01-16 00:39:57 +0100 <jreicher> I know. That's kind of what I mean by "fine line". We seem to be saying we've got "observable", "unobservable", and then something like "observable in principle" (conceivable?)
2026-01-16 00:39:34 +0100 <Leary> jreicher: SillyType caps out at omega since you can only "add 1" on the left to get 1 + omega = omega; there's no omega + 1.
2026-01-16 00:39:17 +0100 <int-e> No it's not the same.
2026-01-16 00:39:12 +0100 <jreicher> (I'm just arguing devil's advocate now)
2026-01-16 00:39:08 +0100 <EvanR> are you sure?
2026-01-16 00:39:02 +0100 <jreicher> ...just like infinitely running programs are not observable
2026-01-16 00:38:43 +0100 <int-e> like, sure, you can pretend that there is an element of SillyType for every ordinal number. Or that there's some other unobservable feature that makes the values more plentiful. There's no purpose to it though, since none of this will be observable.
2026-01-16 00:38:22 +0100 <EvanR> (like 1)
2026-01-16 00:38:12 +0100 <EvanR> it's about the number of possible streams
2026-01-16 00:38:07 +0100 <EvanR> you're not asking about the number of 1s in the stream
2026-01-16 00:37:54 +0100 <jreicher> int-e: which is why I queried the use of an "infinitely running program" to begin with. It's an interesting dividing line.
2026-01-16 00:37:38 +0100 <EvanR> if this is uncountable then, I'll eat my hat
2026-01-16 00:37:25 +0100 <EvanR> there's like 1 possible value of SillyType
2026-01-16 00:37:24 +0100 <int-e> you're also stepping beyond what's useful for modelling program semantics
2026-01-16 00:37:17 +0100trickard_(~trickard@cpe-84-98-47-163.wireline.com.au)
2026-01-16 00:37:03 +0100trickard_(~trickard@cpe-84-98-47-163.wireline.com.au) (Read error: Connection reset by peer)
2026-01-16 00:36:27 +0100 <jreicher> OK, but depending on what we allow for BitStream, can't I be allowed to construct all the aleph numbers from SillyType? That would make it uncountable i think
2026-01-16 00:35:52 +0100 <int-e> So it's nothing like a bit stream.
2026-01-16 00:35:31 +0100 <int-e> jreicher: Anyway, at an intuitive level, SillyType has no bits that you could flip to make Cantor's diagonal argument work.
2026-01-16 00:35:25 +0100merijn(~merijn@host-cl.cgnat-g.v4.dfn.nl) (Ping timeout: 264 seconds)
2026-01-16 00:35:03 +0100 <EvanR> and subfinite
2026-01-16 00:34:23 +0100 <EvanR> there's other fun stuff like subcountable
2026-01-16 00:33:55 +0100 <monochrom> so "more than" is helpful for me.
2026-01-16 00:33:41 +0100 <monochrom> For BitStream I'm using: if a subset is uncountable, then a superset is also uncountable.
2026-01-16 00:33:13 +0100 <monochrom> Sure. That's doesn't get you anywhere per se.
2026-01-16 00:32:53 +0100 <monochrom> (You can also attempt diagonalization on SillyType and get stuck.)
2026-01-16 00:32:49 +0100 <jreicher> monochrom: am I allowed to say SillyType has more the infinite unary strings?
2026-01-16 00:32:25 +0100 <monochrom> (so use Cantor diagonlization again)
2026-01-16 00:32:08 +0100 <monochrom> BitStream has more than infinite bit strings.
2026-01-16 00:31:40 +0100 <jreicher> monochrom: what's your preferred proof that bitstream is uncountable? I'm looking for what it uses that SillyType isn't entitled to
2026-01-16 00:31:29 +0100 <int-e> 1^N has cardinality 1; 2^N or 3^N is uncountable.
2026-01-16 00:31:21 +0100 <monochrom> 2-colourability is polynomial-time, 3-colourability is NP-complete.
2026-01-16 00:31:10 +0100 <int-e> bitstream adds additional observations for each natural number.
2026-01-16 00:30:54 +0100 <monochrom> SillyType is countable, BitStream is uncountable.
2026-01-16 00:30:51 +0100 <int-e> jreicher: NO!
2026-01-16 00:30:35 +0100 <jreicher> monochrom: hang on, are you now saying bitstream is countable? I was hoping that, having proved SillyType is countable, you'd now prove bitstream is uncountable.
2026-01-16 00:30:22 +0100 <monochrom> Generally there are multiple instance when switching from 1 to 2, or 2 to 3, or 3 to 4 makes breaking changes.
2026-01-16 00:30:04 +0100merijn(~merijn@host-cl.cgnat-g.v4.dfn.nl) merijn
2026-01-16 00:29:56 +0100__monty__(~toonn@user/toonn) (Quit: leaving)
2026-01-16 00:29:51 +0100k0zy(~user@user/k0zy) k0zy
2026-01-16 00:29:51 +0100k0zy(~user@75-164-179-179.ptld.qwest.net) (Changing host)
2026-01-16 00:29:43 +0100k0zy(~user@75-164-179-179.ptld.qwest.net)
2026-01-16 00:29:37 +0100 <int-e> Sure. It's morally finite ("morally" being the view where you don't have bottoms)
2026-01-16 00:29:36 +0100 <monochrom> But intuitively I'm not surprised. Expressing natural numbers in unary requires n units of memory for n; "merely" switching to binary, that drops down to lg n.
2026-01-16 00:28:51 +0100 <jreicher> And so SillyType is countable, yes?
2026-01-16 00:27:29 +0100 <monochrom> I map 0 to the infinite stream z = I z, 1 to bottom, 2 to I bottom, 3 to I (I bottom), etc.
2026-01-16 00:26:51 +0100 <jreicher> Every proof I sketch out results in an inconsistency.
2026-01-16 00:26:25 +0100 <jreicher> No, prove away, please. I'd like to understand.