Stathis Papaioannou wrote: > Peter Jones writes: > > >>There is a very impoertant difference between "computations do >>not require a physical basis" and "computations do not >>require any *particular* physical basis" (ie computations can be >>physical >>implemented by a wide variety of systems) > > > Yes, but any physical system can be seen as implementing any computation with > the appropriate > rule mapping physical states to computational states.
I think this is doubtful. For one thing there must be enough distinct states. It's all very well to imagine a mapping between a rock and my computer idealized as isolated closed systems - but in fact they are not isolated close systems. When you're talking about simulating the universe in computation it has a lot more states than a rock and it isn't close either. >Attempts are made to put constraints on what > counts as implementation of a computation in order to avoid this > uncomfortable idea, but it > doesn't work unless you say that certain implementations are specially > blessed by God or something. > So at least you have to say that every computation is implemented if any > physical universe at all > exists, even if it is comprised of a single atom which endures for a > femtosecond. That's an absurd > amount of responsibility for a little atom, and it makes more sense to me > (although I can't at the > moment think of a proof) to say that the atom is irrelevant, and the > computations are implemented > anyway by virtue of their status as mathematical objects. Or by virtue of there being universes. Brent Meeker --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Everything List" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/everything-list -~----------~----~----~----~------~----~------~--~---
