Re: Is the universe computable?

From: Stephen Paul King <stephenk1.domain.name.hidden>
Date: Tue, 13 Jan 2004 20:13:56 -0500

Dear Wei, Georges, et al,

    Where does the notion of computational resources factor in this?

Stephen

----- Original Message -----
From: "Wei Dai" <weidai.domain.name.hidden>
To: "Georges Quenot" <Georges.Quenot.domain.name.hidden>
Cc: <everything-list.domain.name.hidden>
Sent: Monday, January 12, 2004 8:50 PM
Subject: Re: Is the universe computable?


> On Tue, Jan 06, 2004 at 05:32:05PM +0100, Georges Quenot wrote:
> > Many other way of simulating the universe could be considered like
> > for instance a 4D mesh (if we simplify by considering only general
> > relativity; there is no reason for the approach not being possible in
> > an even more general way) representing a universe taken as a whole
> > in its spatio-temporal aspect. The mesh would be refined at each
> > iteration. The relation between the time in the computer and the time
> > in the universe would not be a synchrony but a refinement of the
> > resolution of the time (and space) in the simulated universe as the
> > time in the computer increases.
> >
> > Alternatively (though both views are not necessarily exclusive), one
> > could use a variational formulation instead of a partial derivative
> > formulation in order to describe/build the universe leading again to
> > a construction in which the time in the computer is not related at
> > all to the time in the simulated universe.
>
> Do you have references for these two ideas? I'm wondering, suppose the
> universe you're trying to simulate contains a computer that is running a
> factoring algorithm on a large number, in order to cryptanalyze somebody's
> RSA public key. How could you possibly simulate this universe without
> starting from the beginning and working forward in time? Whatever
> simulation method you use, if somebody was watching the simulation run,
> they'd see the input to the factoring algorithm appear before the output,
> right?
>
>
Received on Tue Jan 13 2004 - 20:17:26 PST