12.1 SOME PROBLEMS THAT CANNOT BE SOLVED BY TURING MACHINES

The argument that the power of mechanical computations is limited is not surprising. Intuitively we know that many vague and speculative questions require special insight and reasoning well beyond the capacity of any computer that we can now construct or even foresee. What is more interesting to computer scientists is that there are questions that can be clearly and simply stated, with an apparent possibility of an algorithmic solution, but which are known to be unsolvable by any computer.

Computability and Decidability

In Definition 9.4, we stated that a function f on a certain domain is said to be computable if there exists a Turing machine that computes the value of f for all arguments ...

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