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From: Mikko <mikko.levanto@iki.fi>
Newsgroups: comp.theory
Subject: Re: The input to HHH(DDD) specifies a non-halting sequence of configurations +++
Date: Tue, 17 Jun 2025 12:32:08 +0300
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On 2025-06-16 20:08:35 +0000, olcott said:

> On 6/16/2025 6:40 AM, Mikko wrote:
>> On 2025-06-15 13:57:01 +0000, olcott said:
>> 
>>> On 6/15/2025 3:44 AM, Fred. Zwarts wrote:
>>>> Op 14.jun.2025 om 16:07 schreef olcott:
>>>>> On 6/13/2025 6:02 AM, Mikko wrote:
>>>>>> On 2025-06-11 14:03:41 +0000, olcott said:
>>>>>> 
>>>>>>> On 6/11/2025 3:20 AM, Mikko wrote:
>>>>>>>> On 2025-06-10 15:41:33 +0000, olcott said:
>>>>>>>> 
>>>>>>>>> On 6/10/2025 6:41 AM, Mikko wrote:
>>>>>>>>>> On 2025-06-10 00:47:12 +0000, olcott said:
>>>>>>>>>> 
>>>>>>>>>>> On 6/9/2025 7:26 PM, Richard Damon wrote:
>>>>>>>>>>>> On 6/9/25 10:43 AM, olcott wrote:
>>>>>>>>>>>>> On 6/9/2025 5:31 AM, Fred. Zwarts wrote:
>>>>>>>>>>>>>> Op 09.jun.2025 om 06:15 schreef olcott:
>>>>>>>>>>>>>>> On 6/8/2025 10:42 PM, dbush wrote:
>>>>>>>>>>>>>>>> On 6/8/2025 11:39 PM, olcott wrote:
>>>>>>>>>>>>>>>>> On 6/8/2025 10:32 PM, dbush wrote:
>>>>>>>>>>>>>>>>>> On 6/8/2025 11:16 PM, olcott wrote:
>>>>>>>>>>>>>>>>>>> On 6/8/2025 10:08 PM, dbush wrote:
>>>>>>>>>>>>>>>>>>>> On 6/8/2025 10:50 PM, olcott wrote:
>>>>>>>>>>>>>>>>>>>>> void DDD()
>>>>>>>>>>>>>>>>>>>>> {
>>>>>>>>>>>>>>>>>>>>>    HHH(DDD);
>>>>>>>>>>>>>>>>>>>>>    return;
>>>>>>>>>>>>>>>>>>>>> }
>>>>>>>>>>>>>>>>>>>>> 
>>>>>>>>>>>>>>>>>>>>> The *input* to simulating termination analyzer HHH(DDD)
>>>>>>>>>>>>>>>>>>>> 
>>>>>>>>>>>>>>>>>>>> No it's not, as halt deciders / termination analyzers work with algorithms,
>>>>>>>>>>>>>>>>>>> 
>>>>>>>>>>>>>>>>>>> That is stupidly counter-factual.
>>>>>>>>>>>>>>>>>>> 
>>>>>>>>>>>>>>>>>> 
>>>>>>>>>>>>>>>>>> That you think that shows that
>>>>>>>>>>>>>>>>> 
>>>>>>>>>>>>>>>>> My understanding is deeper than yours.
>>>>>>>>>>>>>>>>> No decider ever takes any algorithm as its input.
>>>>>>>>>>>>>>>> 
>>>>>>>>>>>>>>>> But they take a description/specification of an algorithm,
>>>>>>>>>>>>>>> 
>>>>>>>>>>>>>>> There you go.
>>>>>>>>>>>>>>> 
>>>>>>>>>>>>>>>> which is what is meant in this context.
>>>>>>>>>>>>>>> 
>>>>>>>>>>>>>>> It turns out that this detail makes a big difference.
>>>>>>>>>>>>>>> 
>>>>>>>>>>>>>>>> And because your HHH does not work with the description/ specification 
>>>>>>>>>>>>>>>> of an algorithm, by your own admission, you're not working on the 
>>>>>>>>>>>>>>>> halting problem.
>>>>>>>>>>>>>>>> 
>>>>>>>>>>>>>>> 
>>>>>>>>>>>>>>> HHH(DDD) takes a finite string of x86 instructions
>>>>>>>>>>>>>>> that specify that HHH simulates itself simulating DDD.
>>>>>>>>>>>>>> 
>>>>>>>>>>>>>> And HHH fails to see the specification of the x86 instructions. It 
>>>>>>>>>>>>>> aborts before it can see how the program ends.
>>>>>>>>>>>>>> 
>>>>>>>>>>>>> 
>>>>>>>>>>>>> This is merely a lack of sufficient technical competence
>>>>>>>>>>>>> on your part. It is a verified fact that unless the outer
>>>>>>>>>>>>> HHH aborts its simulation of DDD that DDD simulated by HHH
>>>>>>>>>>>>> the directly executed DDD() and the directly executed HHH()
>>>>>>>>>>>>> would never stop running. That you cannot directly see this
>>>>>>>>>>>>> is merely your own lack of sufficient technical competence.
>>>>>>>>>>>> 
>>>>>>>>>>>> And it is a verified fact that you just ignore that if HHH does in fact 
>>>>>>>>>>>> abort its simulation of DDD and return 0, then the behavior of the 
>>>>>>>>>>>> input, PER THE ACTUAL DEFINITIONS, is to Halt, and thus HHH is just 
>>>>>>>>>>>> incorrect.
>>>>>>>>>>>> 
>>>>>>>>>>> 
>>>>>>>>>>> void DDD()
>>>>>>>>>>> {
>>>>>>>>>>>    HHH(DDD);
>>>>>>>>>>>    return;
>>>>>>>>>>> }
>>>>>>>>>>> 
>>>>>>>>>>> How the f-ck does DDD correctly simulated by HHH
>>>>>>>>>>> reach its own "return" statement final halt state?
>>>>>>>>>> 
>>>>>>>>>> If HHH is not a decider the question is not interesting.
>>>>>>>>> 
>>>>>>>>> I switched to the term: "termination analyzer" because halt deciders
>>>>>>>>> have the impossible task of being all knowing.
>>>>>>>> 
>>>>>>>> The termination problem is in certain sense harder than the halting
>>>>>>>> problem.
>>>>>>> 
>>>>>>> Not at all
>>>>>> 
>>>>>> That's in another sense in which nothing is harder than impossible.
>>>>>> 
>>>>>>> void DDD()
>>>>>>> {
>>>>>>>    HHH(DDD);
>>>>>>>    return;
>>>>>>> }
>>>>>>> 
>>>>>>> If HHH only determines non-halting correctly for the
>>>>>>> above input and gets the wrong answer on everything
>>>>>>> else then HHH *is* a correct termination analyzer.
>>>>>> 
>>>>>> It is not a correct termination analyzer if if gives the wrong answer.
>>>>> 
>>>>> *Key verified facts such that disagreement is inherently incorrect*
>>>>> 
>>>>> (a) HHH(DDD) does not correctly report on the behavior of its caller.
>>>> 
>>>> Irrelevant. HHH should decide about the program specified in the input, 
>>>> whether or not it is the same code used by the caller.
>>> 
>>> In other words you do not understand that a partial
>>> halt decider is not allowed to report on the behavior
>>> of its caller and only allowed to report on the behavior
>>> specified by the sequence of state transitions specified
>>> by its input.
>> 
>> It is not allowed to report incorrectly. There are no prohibitions
>> against correct reporting.
> 
> And you do not understand which is which.

Of course I do. That is clearly stated in the definition of "partial
halt decider".

-- 
Mikko