Re: How do computations actually work?

On 5/24/25 12:06 PM, olcott wrote:

On 5/24/2025 10:15 AM, dbush wrote:

On 5/24/2025 11:13 AM, olcott wrote:

On 5/24/2025 2:39 AM, Mikko wrote:

On 2025-05-23 16:10:19 +0000, olcott said:
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On 5/23/2025 2:14 AM, Mikko wrote:

On 2025-05-23 03:31:15 +0000, olcott said:
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On 5/22/2025 10:23 PM, wij wrote:

On Thu, 2025-05-22 at 21:47 -0500, olcott wrote:

[cut]

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Q: How do computations actually work?
A: Computation is merely step-by-step algorithm.
Nothing says it has to be TM.
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Do the exercises in textbooks first before any claim of it.
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int main()
{
   DD(); // by what steps can the HHH that DD calls
}       // report on the behavior its caller?

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If we don't insist that the report be correct:
1. guess
2. tell what was guessed

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This does not work because all computable functions
that implement termination analyzers must compute
the mapping from their input finite string according
to the behavior that it specifies.

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Wrong. There is no need to compute "the" mapping if a the report
needs not be correct. Some other mapping is enough to produce
some report.
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int sum(int x, int y) { return 5; }
Does not compute any function because it ignores its inputs.
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Sure it does.  It computes this function:
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For all integers X and Y:
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(X,Y) maps to 5
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The only requirements for mapping is a function is that inputs correspond to outputs as per the given mapping, and the mathematical function above is mapped by the above C function "sum".

 OK
 int main()
{
   DD(); // How does the HHH that DD calls report on the
}       // actual behavior of its actual caller?
 

That's its problem, and shows the programmer doesn't know what he is talking about.
Since DD includes a call to HHH(DD) that call is NOT asking HHH to answer about "its caller" but about the machine represented to it by the code pointed to by the input paramater.
Since to even talk about this, HHH must be a program, and thus HHH(x) must have a specifially defined result, HHH(DD) must return that specifically defined result, and thus DD() will have a specifically defined behaivior.
The fact that behavior doesn't match what HHH(DD) returned, just says that it was wrong.
The fact that no possible program could return the correct answer for the DD that calls it with the repreasentation of itself, means that the question is shown to be uncomputable.
That doesn't make it "invalid" as there *IS* a correct answer for ANY given DD built on a specific HHH, the answer will just always be the opposite of what that HHH(DD) returns.
Sorry, you are just showing you stupidity and lack of understanding of what you are talking about, and that you don't care what "Truth" actually says, you just will repeat you ignorant lies, because of your reckless disregard for the truth.