• wicked@programming.dev
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    21 hours ago

    Most of the “undecidable” are only undecidable for a subset of the problem instances, while a vast number of instances can be even trivially decidable. For example in the undecidable halting problem, both you and a computer can trivially deduce that while(true) will not halt. In the same way a computer can deduce that many instances of two pieces of code are semantically equivalent.

    I’d like to see an instance of the problem where a human could decide it and the computer could not.

    • Farooq@realbitcoin.cash
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      20 hours ago

      Hey. The number of problems which can are decidable are infinite as are those which are not. But as soon as there is a backward jump in your code, a Turing machine most likely won’t be able to decide if it’ll halt or not. The while(true) is an exception. In the real world we have a great number of programs whose loops cannot be decided by a Turing machine. But the programmer who has written the code knows when the loop will terminate.

      If we see the machine code, if there is a conditional backward jump(unlike while(true) which is unconditional), in the general case it’s undecidable.

      • wicked@programming.dev
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        11 hours ago

        Backwards jumps are equally decidable for turing machines as for humans. Compiler and static code linters can trace through very complicated code and know that it will or will not halt, and optimize or warn based on the result.

        I believe there’s nothing special about human computation abilities. Anything that is decidable by a human will be also decidable by a computer.

        Please prove me wrong by showing a counter example.

        • Farooq@realbitcoin.cash
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          26 minutes ago

          I don’t have to prove anything to anyone. Nor I’ve got the time for this. It’s up to you to do your research. I have done mine and shared the results. You can take it or leave it.