Sujet : Re: Can D simulated by H terminate normally?
De : F.Zwarts (at) *nospam* HetNet.nl (Fred. Zwarts)
Groupes : comp.theoryDate : 30. Apr 2024, 10:46:32
Autres entêtes
Organisation : A noiseless patient Spider
Message-ID : <v0qb59$2bsfc$1@dont-email.me>
References : 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
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Op 29.apr.2024 om 21:04 schreef olcott:
On 4/29/2024 1:19 PM, Alan Mackenzie wrote:
olcott <polcott333@gmail.com> wrote:
On 4/29/2024 11:17 AM, Alan Mackenzie wrote:
olcott <polcott333@gmail.com> wrote:
On 4/29/2024 10:23 AM, Alan Mackenzie wrote:
olcott <polcott333@gmail.com> wrote:
On 4/29/2024 9:37 AM, Alan Mackenzie wrote:
In comp.theory olcott <polcott333@gmail.com> wrote:
On 4/28/2024 1:39 PM, Richard Damon wrote:
On 4/28/24 2:19 PM, olcott wrote:
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[ .... ]
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Even the term "halting" is problematic.
For 15 years I thought it means stops running for any reason.
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[ .... ]
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Having been aborted (if such were possible) is merely another final
state for a TM.
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No it definitely is not.
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In a TM, each state is either a final state or a non-final state. Are
you arguing for a third alternative, or do you think that "having been
aborted" is a non-final state? If the latter, what state does the TM
change to next?
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Aborted means completely dead as if you pulled the power cord
on your computer.
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A turing machine has no power cord to pull. You didn't answer my point;
you evaded it.
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When the payroll system crashes 10% of the way through calculating
payroll we cannot say that everyone has been paid.
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Of course not, but it has nevertheless reached a final state, an
unsatisfactory one, since it is no longer running on the computer.
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That is not what "theory of computation" {final state} means.
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I think it is. What do you think "final state" means, and how is "having
been aborted" not one?
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Core dump abnormal termination does not count as the program
correctly finished its processing.
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There is no notion of "correct" in a turing machine.
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In other words when a TM computes the sum of 2 + 3 and derives
999999999999999999999999999 then that is just fine.
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Don't be idiotic. A TM that gets that answer from those starting
conditions isn't calculating their sum; it's doing something else.
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The ONLY way that we can determine if any computation is correct
is when it meets its specification. When a TM is specified to
calculate the sum of a pair of decimal integers and it derives
any decimal integer other than 5 from inputs 2,3 then it is incorrect.
Changing the subject. The question is not whether it is correct, but whether it halts. Incorrect programs exist and even those program may halt.