Liste des Groupes | Revenir à c theory |
On 5/23/2025 2:17 AM, Mikko wrote:And what is wrong with his definition?On 2025-05-23 05:25:30 +0000, olcott said:Is is not supposed to be an English sentence nitwit.
>On 5/22/2025 8:24 PM, Mike Terry wrote:>On 22/05/2025 06:41, Richard Heathfield wrote:>On 22/05/2025 06:23, Keith Thompson wrote:>Richard Heathfield <rjh@cpax.org.uk> writes:>On 22/05/2025 00:14, olcott wrote:[...]On 5/21/2025 6:11 PM, Richard Heathfield wrote:>>Turing proved that what you're asking is impossible.That is not what he proved.
>
Then you'll be able to write a universal termination analyser that can
correctly report for any program and any input whether it halts. Good
luck with that.
Not necessarily.
Of course not. But I'm just reflecting. He seemed to think that my inability to write the kind of program Turing envisaged (an inability that I readily concede) is evidence for his argument. Well, what's sauce for the goose is sauce for the gander.
>Even if olcott had refuted the proofs of the>
insolvability of the Halting Problem -- or even if he had proved
that a universal halt decider is possible
And we both know what we both think of that idea.
>-- that doesn't imply>
that he or anyone else would be able to write one.
Indeed.
>I've never been entirely clear on what olcott is claiming.>
Nor I. Mike Terry seems to have a pretty good handle on it, but no matter how clearly he explains it to me my eyes glaze over and I start to snore.
Hey, it's the way I tell 'em!
>
Here's what the tabloids might have said about it, if it had made the front pages when the story broke:
>
COMPUTER BOFFIN IS TURING IN HIS GRAVE!
>
An Internet crank claims to have refuted Linz HP proof by creating a
Halt Decider that CORRECTLY decides its own "impossible input"!
The computing world is underwhelmed.
>
Better? (Appologies for the headline, it's the best I could come up with.)
>
Mike.
>
When Ĥ is applied to ⟨Ĥ⟩
Ĥ.q0 ⟨Ĥ⟩ ⊢* embedded_H ⟨Ĥ⟩ ⟨Ĥ⟩ ⊢* Ĥ.qy ∞
Ĥ.q0 ⟨Ĥ⟩ ⊢* embedded_H ⟨Ĥ⟩ ⟨Ĥ⟩ ⊢* Ĥ.qn
That is not a valid sentence: there is an subordinate clause and two
main clauses but nothing that combines the main clauses to an overall
meaning.
>
It is a simplification of the Linz definition of Ĥ.
On the top of page 3:
https://www.liarparadox.org/Linz_Proof.pdf
When Ĥ is applied to ⟨Ĥ⟩
Ĥ.q0 ⊢* embedded_H ⟨Ĥ⟩ ⟨Ĥ⟩ ⊢* Ĥ.qy ∞
Ĥ.q0 ⟨Ĥ⟩ ⊢* embedded_H ⟨Ĥ⟩ ⟨Ĥ⟩ ⊢* Ĥ.qn
(a) Ĥ copies its input ⟨Ĥ⟩But that isn't what happens, since the emulation started in (c) will eventually abort its simulation and goe to qn, since that is what you have claimed your H does, showing that it didn't do that CORRECTLY, it just did it, and made itself wrong.
(b) Ĥ invokes embedded_H ⟨Ĥ⟩ ⟨Ĥ⟩
(c) embedded_H simulates ⟨Ĥ⟩ ⟨Ĥ⟩
(d) simulated ⟨Ĥ⟩ copies its input ⟨Ĥ⟩
(e) simulated ⟨Ĥ⟩ invokes simulated embedded_H ⟨Ĥ⟩ ⟨Ĥ⟩
(f) simulated embedded_H simulates ⟨Ĥ⟩ ⟨Ĥ⟩
(g) goto (d) with one more level of simulation
Les messages affichés proviennent d'usenet.