Hi Norman, Only when you demand that the computations be done in real time there is a problem. My point is that this problem is not relevant.
Any TM that you can build will have limitations because of the laws of physics. Suppose that simulating the time evolution of 1 isolated cubic meter of space containing matter for 1 second takes at least 1 billion years for a computer the size of our solar system. Then I would say that I can simulate a few seconds of your consciousness because you only experience simulated time. You may say that because your simulated brain can't interact with the rest of the (real) universe this doesn't qualify as a ''bona fide'' simulation. Saibal ----- Original Message ----- From: "Norman Samish" <[EMAIL PROTECTED]> To: "Saibal Mitra" <[EMAIL PROTECTED]> Sent: Tuesday, September 06, 2005 05:48 AM Subject: Re: What Computationalism is and what it is *not* > Hi Saibal, > > Thanks for your reply. But semantics once again rears its ugly head! > Norman > > ----- Original Message ----- > From: "Saibal Mitra" <[EMAIL PROTECTED]> > To: "Norman Samish" <[EMAIL PROTECTED]>; <firstname.lastname@example.org> > Sent: Monday, September 05, 2005 3:08 PM > Subject: Re: What Computationalism is and what it is *not* > > > Hi Norman, > > (SM) A TM in our universe can simulate you living in a virtual universe. If > your universe is described by the same laws of physics as ours, then most > physicists believe that the TM would have to work in a nonlocal way from > your perspective. > > (NS) What do you mean by "nonlocal"? Wikipedia says "Nonlocality in quantum > mechanics, refers to the property of entangled quantum states in which both > the entangled states "collapse" simultaneously upon measurement of one of > their entangled components, regardless of the spatial separation of the two > states." I don't understand what that has to do with the TM. > > (SM) Is this a problem? I don't think so, because the TM doesn't exist in > your universe, it exists in our universe and it doesn't violate locality > here. The TM generates your universe in which locality cannot be violated. > So, I don't see the problem. > > (NS) Are you saying that the universe that the Turing Machine simulates is > different from the one that I'm in, and in this simulated universe the speed > limits on the speed of the TM don't apply? No - that can't be it. I'm > sorry - I guess I don't know what you mean. The "problem" that I posed is > that I don't understand how a finite-speed Turing Machine can simulate a > universe, contrary to the assertions of the Church Thesis. Whether or not > I'm in the universe to be simulated seem irrelevant. The computation in > such a simulation is so immense that it must take a faster-than-light TM, > which is not possible. Therefore, it seems to me, computationalism must be > false. > ------------------------------------------------- Defeat Spammers by launching DDoS attacks on Spam-Websites: http://www.hillscapital.com/antispam/