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From: Keith Thompson <Keith.S.Thompson+u@gmail.com>
Newsgroups: comp.theory,sci.logic
Subject: Re: Michael Sipser of MIT validates the notion of a simulating halt decider
Date: Thu, 13 Oct 2022 11:20:15 -0700
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olcott <none-ya@beez-waxes.com> writes:
> On 10/13/2022 12:42 PM, Keith Thompson wrote:
>> olcott <polcott2@gmail.com> writes:
>> [...]
>>> *Professor Sipser has agreed to this definition of halt decider*
>>> If H does correctly determine that its correct simulation
>>> of D would never stop running unless aborted, then it
>>> would be correct for H to abort this simulation and report
>>> that D specifies a non-halting sequence of configurations.
>> [...]
>> Does that imply that he agreed that a halt decider is possible?
>> I'm sure you think he did, but did he agree to that explicitly?
>> 
>
> Professor Sipser specifically approved this exact verbiage as the
> abstract to my paper, linked below at 11:29:23 AM today:
>
> <Sipser approved abstract>
> MIT Professor Michael Sipser has agreed that the following verbatim
> paragraph is correct (he has not agreed to anything else in this
> paper):
>
> If simulating halt decider H correctly simulates its input D until H
> correctly determines that its simulated D would never stop running 
> unless aborted then H can abort its simulation of D and correctly
> report that D specifies a non-halting sequence of configurations.
> </Sipser approved abstract>
>
> to this paper:
>
> *Rebutting the Sipser Halting Problem Proof*
> https://www.researchgate.net/publication/364302709_Rebutting_the_Sipser_Halting_Problem_Proof

What is the point of repeating what you wrote earlier?  You didn't
answer my question.  (I suspect you know that, and are being
deliberately evasive.)

If two distinct prime numbers are both even, then the difference between
them is a non-zero even number.  I'm guessing that Professor Sipser
would agree with that statement, but it would not imply that he agrees
that there are two distinct even prime numbers.

Similarly, I see no evidence that Professor Sipser agrees that a
"simulating halt decider" is possible, only a trivial agreement about
what would happen if it were possible.

-- 
Keith Thompson (The_Other_Keith) Keith.S.Thompson+u@gmail.com
Working, but not speaking, for Philips
void Void(void) { Void(); } /* The recursive call of the void */