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How much is known about nondeterministic linear time? I'm aware that $$ \mathrm{NTIME}(n) \neq \mathrm{DTIME}(n).$$ Is there an $m > 1$ so that $\mathrm{NTIME}(n) \not\subset \mathrm{DTIME}(n^m)$? Are there any arguments that $\mathrm{NTIME}(n) \subset \mathrm{P}$ should be unlikely?

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    $\begingroup$ NTIME(n)⊆P is equivalent to P=NP by padding argument. $\endgroup$ Commented Feb 6, 2013 at 12:23
  • $\begingroup$ Ahh wonderful, that answers my question very quickly! I shouldn't really need the other part of the question at this point. Thank you! $\endgroup$ Commented Feb 6, 2013 at 13:32
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    $\begingroup$ And no value k>1 is known such that NTIME(n)⊈DTIME(n^k), because even a value k>1 with a weaker condition NTIME(n^k)⊈DTIME(n^k) is not known. See this question by Bruno and the answer by Ryan Williams. (The linked question only talks about k≥2, but if we knew that NTIME(n^k)⊈DTIME(n^k) for some noninteger k between 1 and 2, then we would also know NTIME(n^2)⊈DTIME(n^2) again by padding argument.) $\endgroup$ Commented Feb 6, 2013 at 17:56
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    $\begingroup$ @Tsuyoshi, could you post your comments as an answer so the question becomes answered? $\endgroup$
    – Kaveh
    Commented Feb 6, 2013 at 19:45
  • $\begingroup$ NTIME(n) and P (or NP) are incomparable because NTIME(n) is not closed under reductions $\endgroup$
    – PsySp
    Commented Oct 6 at 14:45

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