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On 2025-05-11 13:21:31 +0000, Mr Flibble said:That ignores a key fact
Flibble’s Leap: Why Behavioral Divergence Implies a Type Distinction inThe halting problem has very simple types: the input is two strings
the Halting Problem
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Summary
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Flibble argues that the Halting Problem's undecidability proof is built on
a category (type) error: it assumes a program and its own representation
(as a finite string) are interchangeable. This assumption fails under
simulating deciders, revealing a type distinction through behavioral
divergence. As such, all deciders must respect this boundary, and
diagonalization becomes ill-formed. This reframing dissolves the paradox
by making the Halting Problem itself an ill-posed question.
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1. Operational Evidence of Type Distinction
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- When a program (e.g., `DD()`) is passed to a simulating halt decider
(`HHH`), it leads to infinite recursion.
- This behavior differs from direct execution (e.g., a crash due to a
stack overflow).
- This divergence shows that the program (as code) and its representation
(as data) are operationally distinct.
- Therefore, treating them as the same "type" (as Turing's proof does)
leads to inconsistency.
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2. Generalization to All Deciders
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- If simulation reveals this type mismatch, then no valid decider can rely
on conflating program and representation.
- Diagonalization (e.g., defining D(x) = if H(x,x) then loop else halt)
necessarily crosses the type boundary.
- The contradiction in the Halting Problem arises from this type error,
not from inherent undecidability.
- Hence, the Halting Problem is ill-defined for self-referential input.
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3. Comparisons to Other Formal Systems
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- In type-theoretic systems (like Coq or Agda), such self-reference is
disallowed:
- Programs must be well-typed.
- Self-referential constructs like `H(x, x)` are unrepresentable if they
would lead to paradox.
- In category theory, morphisms must respect domain/codomain boundaries:
- Reflexive constructions require stratification to avoid logical
inconsistency.
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4. Conclusion
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- The Halting Problem depends on self-reference and diagonalization.
- If these constructs are blocked due to type/category errors, the proof
breaks down.
- Thus, the Halting Problem isn’t undecidable—it’s malformed when it
crosses type boundaries.
- This is not a refutation of Turing, but a reformulation of the problem
under more disciplined typing rules.
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This model mirrors how Russell’s Paradox was avoided in modern logic: not
by solving the contradiction, but by redefining the terms that made the
contradiction possible.
and the output is a bit. The same input can be given to a UTM, so
the input type of the halting problem is the input type of a UTM.
There is no divergence of behaviour: a UTM has only one behaviour for
each input and no other UTM needs be considered.
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