I tried to find FOAR - but failed. You kindly advised to 'show me how' get subscribed, but it was missing from your post. Could you repeat it? John M
On Fri, Mar 22, 2013 at 5:36 AM, Bruno Marchal <marc...@ulb.ac.be> wrote: > Hi John, > > > On 21 Mar 2013, at 21:40, John Mikes wrote: > > Dear Bruno, > it is so fascinating to read about "universal machines". > Is there a place where I could learn in short, understandable terms what > they may be? Then again the difference between a 'Turing machine' and a > 'physical computer' (what I usually call our embryonic Kraxlwerk). > I grew up into my science without computers, got my doctorates in 1948 and > 1967 and faced a computer first on a different continent (USA) in 1980. At > that time I had already ~30 patents and a reputation of a practical > scientist. > So I need more than the 'difference' into the universal. > > Descriptions I saw turned me off. My chemistry-based polymer science does > not give me the base for most (and mostly theoretical!) descriptions. > How'bout common sense base? > > > Actually I quasi-discovered Turing universality by myself when studying > Jacob and Monod 's work on genetic molecular control in bacteria. But I did > not take that very much seriously, until I discovered (in the literature) > the diagonalization technic (Cantor, Kleene) and Church's thesis, which > makes me decide to study math instead of biology. > > May be you could subscribe to the FOAR list, as I will explain all that > there. But if you ask me, I can send it in cc here or provide other > explanations (I think some people are on both list, but this should not be > a problem as it will not be a great number of posts). I dunno. I will see. > > Thanks for telling me your interest, > > Best, > > Bruno > > > > > > On Thu, Mar 21, 2013 at 2:02 PM, Bruno Marchal <marc...@ulb.ac.be> wrote: > >> >> On 21 Mar 2013, at 02:32, Stephen P. King wrote: >> >> Are physical computers truly "universal Turing Machines"? No! They do not >> have infinite tape, not precise read/write heads. They are subject to noise >> and error. >> >> >> >> The infinite tape is not part of the universal machine. A universal >> machine is a number u such that phi_u(x, y) = phi_x(y). >> >> Please concentrate to the thought experiments, the sum will be taken on >> the memories of those who get the continuations, and the extensions. >> >> When a löbian universal number run out of memory, he asks for more memory >> space or write on the wall of the cave, soon or later. And if it does not >> get it it dies, but from the 1p, it will find itself in a situation >> extending the memory (by just 1p indeterminacy). >> >> >> Universal machines are finite entities. Physical Computer are particular >> case of Turing machine, and can emulate all other possible universal >> number, and the same is true for each of them. All universal machine can >> imitate all universal machines. >> But no universal machines can be universal for the notion of a belief, >> knowledge, observation, feeling, etc. In those matter, they can differ a >> lot. >> >> But they are all finite, and their ability is measured by abstracting >> from the time and space (in the number theoretical or computer theoretical >> sense) needed to accomplish the task. >> >> That they have no precise read/write components, makes them harder to >> recognize among the phi_i, but this is not a problem, given that we know >> that we already cannot know which machine we are, and form the first person >> point of view, we are supported by all the relevant machines and >> computations. >> >> And they are all subject to noise and error, (that follows from >> arithmetic). Those noise and errors are their best allies to build more >> stable realities, I guess. >> >> Bruno >> >> >> >> >> http://iridia.ulb.ac.be/~marchal/ >> >> >> >> >> -- >> You received this message because you are subscribed to the Google Groups >> "Everything List" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to everything-list+unsubscr...@googlegroups.com. >> To post to this group, send email to everything-list@googlegroups.com. >> Visit this group at http://groups.google.com/group/everything-list?hl=en. >> For more options, visit https://groups.google.com/groups/opt_out. >> >> >> > > > -- > You received this message because you are subscribed to the Google Groups > "Everything List" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to everything-list+unsubscr...@googlegroups.com. > To post to this group, send email to everything-list@googlegroups.com. > Visit this group at http://groups.google.com/group/everything-list?hl=en. > For more options, visit https://groups.google.com/groups/opt_out. > > > > > http://iridia.ulb.ac.be/~marchal/ > > > > -- > You received this message because you are subscribed to the Google Groups > "Everything List" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to everything-list+unsubscr...@googlegroups.com. > To post to this group, send email to everything-list@googlegroups.com. > Visit this group at http://groups.google.com/group/everything-list?hl=en. > For more options, visit https://groups.google.com/groups/opt_out. > > > -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to everything-list+unsubscr...@googlegroups.com. To post to this group, send email to everything-list@googlegroups.com. Visit this group at http://groups.google.com/group/everything-list?hl=en. For more options, visit https://groups.google.com/groups/opt_out.
