Re: What Computationalism is and what it is *not*

From: Norman Samish <ncsamish.domain.name.hidden>
Date: Thu, 8 Sep 2005 10:08:29 -0700

Hi Saibal,

At last, I may be getting a glimmering of understanding of your point of
view (which doesn't mean that I agree with you). Thanks for your patience.

You seem to be saying that it is irrelevant if a Turing Machine, even one
that operates at the speed of light, takes a billion years to simulate one
second of a cubic meter of space. The fact that it CAN simulate the cubic
meter for one second, irrespective of the time it takes to do so, means that
the computationalist hypothesis is true.

But, as you point out, this isn't a ''bona fide'' simulation because it's
not in "real time."

My problem is that if it's not bona fide then it's imaginary - a Harry
Potter universe - and I don't understand how this imaginary happening can be
a proof of the computationalist hypothesis, or of anything else in the real
universe.

Norman
~~~~~~~~~~~~~~~~~~~~~~~~~~~~
----- Original Message -----
From: "Saibal Mitra" <smitra.domain.name.hidden>
To: "Norman Samish" <ncsamish.domain.name.hidden>
Cc: "everything" <everything-list.domain.name.hidden>
Sent: Thursday, September 08, 2005 8:11 AM
Subject: Re: What Computationalism is and what it is *not*


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" <ncsamish.domain.name.hidden>
To: "Saibal Mitra" <smitra.domain.name.hidden>
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" <smitra.domain.name.hidden>
> To: "Norman Samish" <ncsamish.domain.name.hidden>; <everything-list.domain.name.hidden.com>
> 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.
Received on Thu Sep 08 2005 - 13:31:31 PDT