Quentin Anciaux-2 wrote: > > 2012/9/10 benjayk <benjamin.jaku...@googlemail.com> > >> >> >> > > No program can determine its hardware. This is a consequence of the >> > > Church >> > > Turing thesis. The particular machine at the lowest level has no >> > bearing >> > > (from the program's perspective). >> > If that is true, we can show that CT must be false, because we *can* >> > define >> > a "meta-program" that has access to (part of) its own hardware (which >> > still >> > is intuitively computable - we can even implement it on a computer). >> > >> >> It's false, the program *can't* know that the hardware it has access to >> is >> the *real* hardware and not a simulated hardware. The program has only >> access to hardware through IO, and it can't tell (as never ever) from >> that >> interface if what's outside is the *real* outside or simulated outside. >> <\quote> >> Yes that is true. If anything it is true because the hardware is not even >> clearly determined at the base level (quantum uncertainty). >> I should have expressed myself more accurately and written " "hardware" " >> or >> "relative 'hardware'". We can define a (meta-)programs that have access >> to >> their "hardware" in the sense of knowing what they are running on >> relative >> to some notion of "hardware". They cannot be emulated using universal >> turing >> machines > > > Then it's not a program if it can't run on a universal turing machine. > The funny thing is, it *can* run on a universal turing machine. Just that it may lose relative correctness if we do that. We can still use a turing machine to "run" it and interpret what the result means.
So for all intents and purposes it is quite like a program. Maybe not a program as such, OK, but it certainly can be used precisely in a step-by-step manner, and I think this is what CT thesis means by algorithmically computable. Maybe not, but in this case CT is just a statement about specific forms of algorithms. -- View this message in context: http://old.nabble.com/Why-the-Church-Turing-thesis--tp34348236p34417440.html Sent from the Everything List mailing list archive at Nabble.com. -- You received this message because you are subscribed to the Google Groups "Everything List" group. To post to this group, send email to email@example.com. To unsubscribe from this group, send email to everything-list+unsubscr...@googlegroups.com. For more options, visit this group at http://groups.google.com/group/everything-list?hl=en.