2012/9/11 benjayk <benjamin.jaku...@googlemail.com> > > > Quentin Anciaux-2 wrote: > > > > 2012/9/11 benjayk <benjamin.jaku...@googlemail.com> > > > >> > >> > >> 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. > > > > > > Then you must be wrong... I don't understand your point. If it's a > program > > it has access to the "outside" through IO, hence it is impossible for a > > program to differentiate "real" outside from simulated outside... It's a > > simple fact, so either you're wrong or what you're describing is not a > > program, not an algorithm and not a computation. > OK, it depends on what you mean by "program". If you presume that a program > can't access its "hardware",
I *do not presume it*... it's a *fact*. Quentin > then what I am describing is indeed not a > program. > > But most definitions don't preclude that. Carrying out instructions > precisely and step-by-step can be done with or without access to your > hardware. > > Anyway, meta-programs can be instantiated using real computer (a program > can, in principle, know and utilize part of a more basic computational > layer > if programmed correctly), so we at least know that real computers are > beyond > turing machines. > > benjayk > > -- > View this message in context: > http://old.nabble.com/Why-the-Church-Turing-thesis--tp34348236p34417676.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 everything-list@googlegroups.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. > > -- All those moments will be lost in time, like tears in rain. -- You received this message because you are subscribed to the Google Groups "Everything List" group. To post to this group, send email to everything-list@googlegroups.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.