Re: How Partial Simulations correctly determine non-halting ---Mike Terry Error

Op 05.jun.2024 om 00:16 schreef olcott:

On 6/4/2024 4:26 PM, joes wrote:

Am Tue, 04 Jun 2024 13:02:03 -0500 schrieb olcott:

On 6/4/2024 11:58 AM, Mike Terry wrote:

On 04/06/2024 11:52, Fred. Zwarts wrote:

Op 04.jun.2024 om 12:29 schreef Fred. Zwarts:

Op 03.jun.2024 om 23:24 schreef olcott:

On 6/3/2024 3:09 PM, Fred. Zwarts wrote:

Op 03.jun.2024 om 14:20 schreef olcott:

On 6/3/2024 4:42 AM, Ben Bacarisse wrote:

Mike Terry <news.dead.person.stones@darjeeling.plus.com> writes:
>

*DD correctly simulated by HH would never stop running unless
aborted*
*We can see that the following DD cannot possibly halt when*
*correctly simulated by every HH that can possibly exist*

>
It is very clear that if the simulated HH would halt, then DD would
halt. So your claim comes down to HH not halting when simulating
itself.
>

Mike Terry replied to this and explained it correctly as reply
directly to you On 6/3/2024 12:36 PM, Mike Terry wrote:
>
http://al.howardknight.net/?

STYPE=msgid&MSGI=%3CHlGdnbvc3Ly_YsD7nZ2dnZfqn_adnZ2d%40brightview.co.uk%3E

>
>

He says that there is no infinite recursion, because the simulation
is aborted.
If you want to interpret his reply in this way,

>
Yes, that's my intended meaning
>

then it also shows that neither HH, nor DD are

involved in a recursive recursion. This implies

>
That should be: ... are involved in an infinite recursion, because the
simulation was aborted,

>
Yes.  (There is finite recursive simulation, i.e. H partially simulates
H etc..)
>

which implies ...
>

that none of them reaches their final state.

>
None of their /simulations by H/ reach their final state.  Obviously
there's a huge distinction between the abstract concept of a
computation/halting, and a partial simulation of that computation by
some other program, and I'm surprised anyone (not you specifically)
tolerates confusion on that point.
>
Suppose P(I) is some computation that halts after 13422 steps.  Clearly
a partial simulation of P(I) by H could be abandoned ("aborted") after
8333 steps.  So the /partial simulation by H/ "does not halt", but the
computation P(I) of course halts.
>
I'm not trying to suggest that considering the "halting" behaviour of a
partial simulation by a specific program is a /useful/ thing to be
looking at, but none the less that is what PO is doing...
>

The meaning of these words prove that I am correct about how partial
simulations correctly determine the halt status of their non-halting
inputs.
<Professor Sipser agreed>
</Professor Sipser agreed>

>
You completely missed the point. The simulator absolutely can keep track
of repeating states; it just can't halt if its input doesn't,

 You don't seem to know the first thing about deciders, in that
they must always halt.
 

Yes. And the fact that your decider diagnoses itself as non-halting proves that there is something wrong with your decider.
Get the cream out of your eyes!
        typedef int (*ptr)();  // ptr is pointer to int function in C
        int H(ptr p, ptr i);
        int main()
        {
          H(main, 0);
        }
H diagnoses this program as non-halting. The only reason is obvious: the simulation of H by itself did not reach the final state.