Re: quantum Computing

[juola@bruno.cs.colorado.edu]

  Rick Busdiecker writes:
   > Not true.  What that means is that a polynomial time solution exists
   > for an NFA.  The only part has not been shown.
  
  Mike McNally responds:
  >While we're being picky, I'll point out that (unless I'm wrong of
  >course) it's not really an NFA, but a non-deterministic Turing
  >machine (an "NTM"?) that's the automaton at issue here.
  
That is correct.  As a matter of fact, it's an easy theorem that
an NFA has the same computing capacity as a DFA; it is not known
whether this theorem holds for more powerful machines, and is in
fact the heart of the P ?= NP conjecture.