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Am Mon, 02 Sep 2024 08:42:56 -0500 schrieb olcott:On 9/1/2024 5:48 AM, Fred. Zwarts wrote:Op 31.aug.2024 om 18:15 schreef olcott:On 8/31/2024 10:47 AM, Fred. Zwarts wrote:Op 31.aug.2024 om 17:22 schreef olcott:On 8/31/2024 10:15 AM, Fred. Zwarts wrote:Op 31.aug.2024 om 14:50 schreef olcott:On 8/30/2024 8:31 AM, Mikko wrote:No, the behaviour specified by the finite string does not changeOn 2024-08-29 14:04:05 +0000, olcott said:Although deciders cannot possibly see their own behavior otherOn 8/29/2024 3:00 AM, Mikko wrote:Now you contradict what you said above. You said that decidersOn 2024-08-28 11:46:58 +0000, olcott said:When a TM takes its own machine description as input this is notOn 8/28/2024 2:33 AM, Mikko wrote:What would prevent that if the input language permitsOn 2024-08-27 13:04:26 +0000, olcott said:The computation that they themselves are contained withinOn 8/27/2024 12:45 AM, joes wrote:Why not? A decider always either accepts or rejects itsAm Mon, 26 Aug 2024 18:03:41 -0500 schrieb olcott:Deciders never compute the mapping of the computation thatOn 8/26/2024 7:42 AM, Ben Bacarisse wrote:>Mike Terry <news.dead.person.stones@darjeeling.plus.com>
writes:On 23/08/2024 22:07, Ben Bacarisse wrote:>Yes, and it fits with his thinking it a "trivial remark".We don't really know what context Sipser was given. IExactly my reading. It makes Sipser's agreement
got in touch at the time so I do know he had enough
context to know that PO's ideas were "wacky" and that
had agreed to what he considered a "minor remark".
Since PO considers his words finely crafted and key to
his so-called work I think it's clear that Sipser did
not take the "minor remark" he agreed to to mean what
PO takes it to mean! My own take if that he (Sipser)
read it as a general remark about how to determine some
cases, i.e. that D names an input that H can partially
simulate to determine it's halting or otherwise. We
all know or could construct some such cases.
natural, because it is both correct [with sensible
interpretation of terms], and moreover describes an
obvious strategy that a partial decider might use that
can decide halting for some specific cases. No need for
Sipser to be deceptive or misleading here, when the
truth suffices. (In particular no need to employ
"tricksy" vacuous truth get out clauses just to get PO
off his back as some have suggested.)Is this an accurate phrasing, pete?That aside, it's such an odd way to present an argument:
"I managed to trick X into saying 'yes' to something
vague". In any reasonable collegiate exchange you'd go
back and check: "So even when D is constructed from H, H
can return based on what /would/ happen if H did not stop
simulating so that H(D,D) == false is correct even though
D(D)
halts?". Just imagine what Sipser would say to that!
they themselves are contained within.
input.
cannot possibly be an input.
computations?
always that same behavior as the direct execution of the
machine. It is not the same because it is one level of indirect
reference away.
never conpute the mapping of the computation they themselves are
contained within.
people can see this behavior.
>Now you are saying that they do in a way that might not be asIf is a verified fact that DDD has different behavior before it is
expected.
aborted in the same way that people are hungry before they eat.
when a simulator decides to do the simulation only halfway. It is
just an incorrect simulation.
>than the behavior of DDD after it has been aborted, people are notIf two people are hungry and one of them eats, the other one is
hungry after they eat.
still hungry and needs to eat. It is stupid to say that they are no
longer hungry because they have eaten.
Similarly the simulating HHH is not longer hungry, but the
simulated HHH still is hungry and has not yet eaten.Because this would require it to wait forever,And people (except the stupid ones) can see that, because HHH cannotPeople that are not as stupid can see that HHH cannot wait for itselfThe direct execution of DDD includes the behavior of the emulatedAnd the simulator should also simulate until it sees the behaviour
DDD after it has been aborted.
of after the simulated HHH has aborted its simulator.
to abort its own simulation.
wait for itself,
thus HHH knows that to meet its own requirement to halt it must abort
its simulation.
And because HHH is simulating itself, the simulated HHH also aborts.It can not possibly do this. The outermost directly executed
--Useless stipulation.this means that HHH failed to simulate itself correctlyAs long as HHH emulates its input according to the semantics of the x86
language HHH is correctly emulating this input even if this correct
emulation causes the computer to catch on fire.
AS I HAVE TOLD YOU FAR TOO MANY TIMES CORRECT EMULATION IS ENTIRELY
DETERMINED BY THE SEMANTICS OF THE X86 LANGUAGE.
When DDD calls HHH(DDD) then HHH must emulate itself emulating DDD. If
this causes the emulated HHH to never return THEN THIS EMULATION IS
STIPULATED TO BE CORRECT BY THE ONLY MEASURE OF CORRECT EMULATION, the
semantics of the x86 language.
No simulator can simulate itself.up to the end. HHH cannot possibly simulate itself correctly up to theHHH cannot possibly correctly simulate itself to the end because the x86
end.
code of DDD and HHH specify that HHH cannot simulate itself to the end.
If HHH did simulate itself to the end then HHH WOULD BE WRONG.
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