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I too saw this footnote near the beginning (page 9):

“At the present time very few people believe that P=NP. In other words, almost everybody who has studied the subject thinks that satisfiability cannot be decided in polynomial time. The author of this book, however, suspects that N^O(1)-step algorithms do exist, yet that they’re unknowable. Almost all polynomial time algorithms are so complicated that they lie beyond human comprehension, and could never be programmed for an actual computer in the real world. Existence is different from embodiment.”

But would the existence of such "step algorithms" be fully equivalent to P=NP or a limited case applicable to only a subset of NP problems (i.e. one's thought previously to be NP)?

I don't know the answer and am genuinely curious.




I read that not as 'step algorithms' but as 'algorithms requiring N^(O(1)) steps'; in other words - polynomial time algorithms.

One way to think of this is in terms of galactic algorithms, which are algorithms that incrementally improve the exponent in a polynomial time algorithm, but have constant terms so huge that they're effectively useless, practically. He's suggesting that there could exist a polynomial time algorithm for an NP problem which is similarly useless - but with the additional caveat that we won't even be able to prove theorems about it!




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