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Unfortunately the archive is not peer-reviewed, so anybody can send in stuff.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.
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