On Fri, Jun 5, 2015 , LizR <[email protected]> wrote: > (very much in theory) a TOE would describe everything - it would in > principle be like "Laplace's demon" (though possibly only for a multiverse).
Laplace's demon could make predictions and that is far more difficult than just making a description. Even if the world worked according to Newtonian physics you couldn't predict how 3 bodies of similar mass will interact over the long term, you could do it for 2 bodies and there are a few very specific orbits you can do it for 3 bodies but in general if there are 3 you can only make approximations, there is no exact solution that is general, so the longer the prediction of where the 3 bodies will be the more inaccurate it will be. John K Clark On 6 June 2015 at 09:46, meekerdb <[email protected]> wrote: > >> On 6/5/2015 12:22 PM, John Clark wrote: >> >> On Fri, Jun 5, 2015 , meekerdb <[email protected]> wrote: >> >> >> It's very relevant if you want to know what is a simplified >>> approximation of what. And we both agree that a electronic computer is >>> vastly more complex than it's logical schematic, so why can we make a >>> working model of the complex thing but not make a working model of the >>> simple thing when usually it's easier to make a simple thing than a complex >>> thing? The only answer that comes to mind is that particular simplified >>> approximation is just too simplified and just too approximate to actually >>> do anything. That simplification must be missing something important, >>> matter that obeys the laws of physics. >> >> >> >>> > The trouble with this argument is that the laws of physics are >>> mathematical abstractions. >>> >> >> Mathematicians are always saying that mathematics is a language, but >> what would be the consequences if that were really true? The best way known >> to describe the laws of physics is to write then in the language of >> mathematics, but a language is not the thing the language is describing. >> >> >> I agree the laws of physics are descriptions we invent; but even so they >> are abstractions and not material and what they define is only an >> approximation to what happens in the world. That's what makes them useful >> - they let us make predictions while leaving out a lot of stuff. >> >> I know what you mean, but this statement could be considered a bit > misleading. Unlike the other branches of science, physics at least tries to > be a complete description. Of course it fails in practice, but (very much > in theory) a TOE would describe everything - it would in principle be like > "Laplace's demon" (though possibly only for a multiverse). > > -- > 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 [email protected]. > To post to this group, send email to [email protected]. > Visit this group at http://groups.google.com/group/everything-list. > For more options, visit https://groups.google.com/d/optout. > -- 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 [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
