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Is that true that $Time(O(log(n)))=NTime(O(log(n)))$ iff $P=NP$?
It seems to me to be true, as I only need to take log on both sides, since log of a polynomial is $O(\log(n))$, but I don't know how to derive a proof from this intuition.

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  • $\begingroup$ You can try using the technique of padding. $\endgroup$ May 13, 2017 at 18:33
  • $\begingroup$ OK, this gives me one direction (lhs implies rhs). How about the second direction? $\endgroup$
    – Dudi Frid
    May 14, 2017 at 4:00
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    $\begingroup$ Only one direction of such implications is known. $\endgroup$ May 14, 2017 at 5:02
  • $\begingroup$ Could you please supply me with some citation or a source? $\endgroup$
    – Dudi Frid
    May 14, 2017 at 9:57
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    $\begingroup$ What computation model are you interested in? Turing machine? Random-access machine? $\endgroup$ Sep 12, 2017 at 13:04

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$\mathsf{DLOGTIME\subsetneq NLOGTIME}$. Search in unsorted array is a problem from $\mathsf{NLOGTIME}$, but it can't be solved deterministically in logarithmic time. This is proven. I also think that $\mathsf{NLOGTIME\not\subset DTIME}(o(n))$.

Padding argument here do not have an implication for $\mathsf P$ vs. $\mathsf{NP}$.

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