Re: Ben fails to understand

Am Thu, 04 Jul 2024 09:25:29 -0500 schrieb olcott:

On 10/14/2022 7:44 PM, Ben Bacarisse wrote:

Python <python@invalid.org> writes:

   [comment: as D halts, the simulation is faulty, Pr. Sipser has been
    fooled by Olcott shell game confusion "pretending to simulate" and
    "correctly simulate"]

I don't think that is the shell game.  PO really /has/ an H (it's
trivial to do for this one case) that correctly determines that P(P)
*would* never stop running *unless* aborted.  He knows and accepts that
P(P) actually does stop.  The wrong answer is justified by what would
happen if H (and hence a different P) where not what they actually are.

You seem to like this quote. Do you agree with it?

It is the case that H must abort its simulation of P to prevent its own
non-termination. The directly executed P(P) benefits from H already
having aborted its simulation of P. P correctly simulated H cannot reap
this benefit proving that it is a different sequence of configurations
than the directly executed P(P).

Meaning that H does not simulate P correctly (if it is not the same
sequence of configurations).

In other words: "if the simulation were right the answer would be
right".

I don't think that's the right paraphrase.  He is saying if P were
different (built from a non-aborting H) H's answer would be the right
one.

Which one of these is accurate?

But the simulation is not right. D actually halts.

Thus H(D,D) must abort the simulation of its input to prevent its own
non-termination.

What's wrong is to pronounce that answer as being correct for the D
that does, in fact, stop.

That is a different D that is being simulated in a different memory
process. The executed D(D) only halts because D correctly simulated by H
was aborted.

There should be no difference whether D is simulated or not, otherwise
the simulation is incorrect.

They are not the same instance of D.

They are the same program.

void DDD()
{
   HHH(DDD); // creates new process context
}           // thus not the same DDD as the
             // one that is directly executed.

That context is identical to the one in which DDD is directly executed.

int main()
{
   DDD(DDD);
}

--
Am Fri, 28 Jun 2024 16:52:17 -0500 schrieb olcott:
Objectively I am a genius.