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pengvado comments on Polarized gamma rays and manifest infinity - Less Wrong Discussion

16 Post author: rwallace 30 July 2011 06:56AM

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Comment author: pengvado 03 August 2011 02:00:20PM *  3 points [-]

... but surprising for others e.g. traveling salesman.

A "yes" answer to the decision version of TSP ("is there a path shorter than x?") is straightforwardly demonstrable: just specify the path. A "no" answer is not demonstrable (short of interactive provers): TSP is in NP, not coNP. And an answer to the optimization version of TSP ("find the shortest path") is also not demonstrable (short of interactive provers): it's FP^NP-complete, which is stronger than NP. So I don't see any surprises there.