• solrize@lemmy.ml
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    14 hours ago

    We know for certain do that it is not in NP hard

    It’s likely to be NP-intermediate (outside of P, but not NP-hard), but it is not known.

    (@Kairos@lemmy.today)

    Factoring is at most NP-complete because we have a polynomial time verification for it.

    That means it’s in NP. These terms mean very precise things and it’s easy to get confused, but at the end of the day the new paper didn’t find a faster way to factor.

      • solrize@lemmy.ml
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        7 hours ago

        You wrote “we know for certain do that it [factoring] is not in NP hard”. That sentence is 1) borderline ungrammatical (we usually use NP-hard as an adjective, though it also denotes a set); and 2) in error. We suspect factoring is not NP-hard but we don’t know for certain (consider what happens if P=NP). The error suggests confusion about what these terms mean. If you’re really teaching this subject, can I ask what textbook you are using?

        • a_non_monotonic_function@lemmy.world
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          2 hours ago

          No, we don’t use it as an adjective. It is a set. That’s literally all it is.

          And predicating anything on the assumption that P equals NP is rather absurd. Of course, we can’t rule it out as a possibility. But virtually nobody in the discipline believes that to be the case. And honestly, why would it be? If there were polynomial time solutions to that many problems of that degree of importance, surely we would have discovered something by now.