From: Anders Sandberg (asa@nada.kth.se)
Date: Mon May 17 1999 - 04:24:57 MDT
hal@rain.org writes:
> In that paper, http://xxx.lanl.gov/html/physics/9810010, the authors
> emphasized the one aspect in which CAs are entirely compatible with
> relativity, which is that they are inherently local. The authors then
> claimed to have a way to show that the speed of light would be the
> same in all moving frames in their CA model, but I think they were just
> talking through their hats. (I'm surprised that a paper like this was
> published in what I have found in the past to be a very reliable forum,
> the LANL physics archive.)
Unfortunately the archive is not peer-reviewed, so anybody can send in
stuff. I guess few real crackpots try to post to gr-qc eller hp-th,
but the physics subsection has shown a slow increase in the number of
unorthodox articles of varying quality.
> It does seem that the separation of space and time is inherent to the CA
> model. You could set up a four-dimensional CA array which might represent
> spacetime in some sense, but then what would it mean for the CA to evolve?
> You've already incorporated what we call "time" in the four dimensional
> CA. It just doesn't fit.
You could have a 4D CA representing the whole of spacetime, and then the
evolution rule would correspond to a gradual refinement/convergence to
a stable state which corresponds to the entire history of the
universe.
-- ----------------------------------------------------------------------- Anders Sandberg Towards Ascension! asa@nada.kth.se http://www.nada.kth.se/~asa/ GCS/M/S/O d++ -p+ c++++ !l u+ e++ m++ s+/+ n--- h+/* f+ g+ w++ t+ r+ !y
This archive was generated by hypermail 2.1.5 : Fri Nov 01 2002 - 15:03:44 MST