Re: How the requirements that Professor Sipser agreed to are exactly met --- Mike my best reviewer

On 5/17/2025 9:27 AM, Mike Terry wrote:

On 17/05/2025 09:55, Mikko wrote:

On 2025-05-16 14:47:39 +0000, olcott said:
>

On 5/16/2025 4:26 AM, Mikko wrote:

On 2025-05-15 00:36:21 +0000, Mike Terry said:
>

On 14/05/2025 22:31, Keith Thompson wrote:

olcott <polcott333@gmail.com> writes:

On 5/14/2025 3:51 PM, dbush wrote:

On 5/14/2025 11:45 AM, olcott wrote:

On 5/14/2025 6:20 AM, Richard Damon wrote:

>
And since the DD that HHH is simulating WILL HALT when fully
simulated (an action that HHH doesn't do)

>
*NOT IN THE ACTUAL SPEC*
<MIT Professor Sipser agreed to ONLY these verbatim words 10/13/2022>
     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
>

That Sipser didn't agree what you think the above means:
>

>
If that was actually true then you could provide an
alternative meaning for the exact words stated above.
>
I keep challenging you to provide this alternative
meaning and you dodge because you know that you are
lying about there being any alternative meaning
FOR THE EXACT WORDS LISTED ABOVE.

>
No alternative meaning is needed, just a correct interpretation of the
words (which appear to be incomplete).
>
The quoted sentence is cut off, something that I suspect you didn't
notice.  Here's the full quotation from a previous article:
>

<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>

>
**If** H correctly simulates its input in the manner you claim,
**then** H can correctly report the halting status of D.  (That's a
paraphrase that probably doesn't capture the full meaning; the full
**quotation is above.)
>
To put it another way, If H correctly simulated its input in
the manner you claim, then H could correctly report the halting
status of D.
>
I'm not surprised that Sipser would agree to that.  The problem is
that it's a conditional statement whose premise is impossible.
>
If an equilateral triangle had four sides, then each of its four
vertices would be 90 degrees.  That doesn't actually mean that
there exists an equilateral triangle with four 90-degree vertices,
and in fact no such triangle exists.  Similarly, *if* a general
halt decider existed, then there are a lot of things we could say
about it -- but no general halt decider can exist.
>
I'm not quite 100% confident in my reasoning here.  I invite any
actual experts in computational theory (not you, PO) to criticize
what I've written.

>
I doubt that Sipser would be using your interpretation, relying on a false premise as a clever kind of logical loop-hole to basically fob someone off.

>
The details of H are not known to Sipser, so he can't know whether a
premise is false. It is possible that some simulating partial decider
correctly simulates a part of the behaviour of some D and correctly
determines that the unsimulated part of the behaviour never halts;
for example, if the unsimulated part is a trivial eternal loop. That
one premise is false about HHH with DDD is a part of what was asked.

>
Mike explains all of the details of exactly how a
correct Simulating Halt Decider is derived from
the exact meaning of the words that professor Sipser
agreed to IN THE PART THAT YOU IGNORED

>
No, he does not. He does not even believe that it is possible to derive
a correct Simulating Halt Decider form the exact meaning of any words.
>

 That's correct.
 We could build a correct /partial/ SHD though, which I explained.  The idea behind an PSHD is ok, and a class of HP inputs could be correctly decided with a PSHD.  Obviously a PSHD H could not decide its corresponding H^ input, as the Linz HP proof implies.  Since PO's HHH / does/ decide its corresponding DD (incorrectly), it is not a PSHD, since PSHDs are not allowed to decide incorrectly.  [A correctly coded PSHD HHH would never halt when given its (HHH^,HHH^) input.
 PO's problem is that he misunderstands the entire context of Sipser's words.  Sipser's words concern how a PSHD H could decide some FIXED INPUT D it has been given.

Mike's reviews of my work are at least ten-fold better
than the next best reviewer. Mike is one of the few
people here that really wants an honest dialogue. He
carefully examined my code and has a nearly perfect
understanding.
https://github.com/plolcott/x86utm/blob/master/Halt7.c
Most everyone else only seems to care about rebuttal
at the expense of truth. Keith and Ben also seem to
care about truth.
<MIT Professor Sipser agreed to ONLY these verbatim words 10/13/2022>
     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
On 5/14/2025 7:36 PM, Mike Terry wrote:
https://al.howardknight.net/?STYPE=msgid&MSGI=%3C1003cu5%242p3g1%241%40dont-email.me%3E Just like your SHD does not base its decision on the
actual behavior of the infinite loop after it has
aborted its simulation of this loop, instead it bases
its decision on a different H/D pair that never aborts.
HHH(DDD) does not base its decision on the actual
behavior of DDD after it has aborted its simulation
of DDD, instead it bases its decision on a different
HHH/DDD pair that never aborts.
If an otherwise correct SHD always reported on the
behavior of its input AFTER it aborts then every
input would be determined to be halting.
The key question here that most experts in the theory
of computation would be aware of is the way that functions
computed by models of computation must work.
Is HHH supposed to compute the mapping from its input
on the basis of the behavior specified by this input
or something else?
My presentation using the concrete language of x86 leaves
no doubt exactly what behavior that DDD specifies.
DDD correctly simulated by HHH
*would never stop running unless aborted*

PO wants to interpret them as what happens when H is modified, and D is also modified to reference the new H.  So he's modifying what is supposed to be a fixed input half way through his interpretation.  Sipser would be holding his head in his hands if he knew (and cared) ... :)
  Mike.
 

--
Copyright 2025 Olcott "Talent hits a target no one else can hit; Genius
hits a target no one else can see." Arthur Schopenhauer