Wolfram on Alan Turing's birthday.
blog.wolframalpha.com
blog.wolframalpha.com
In other words, this is exactly the article I expected.
But Wolfram is also a scientist, and the ideals in science are a bit different. A scientist is supposed to be humble, admit the limitations of his work, and acknowledge the contributions of others. This is expressed in the famous quote by Isaac Newton: "If I have seen further it is only by standing on the shoulders of giants." Of course scientists are only human and don't always hold up to that ideal (maybe Newton least of all), but it's still important to recognize the difference between a scientific argument and a sales pitch.
Ironically, this was a quip at the expense of Robert Hooke, who was particularly short in stature.
> What Descartes did was a good step. You have added much several ways, and especially in taking the colours of thin plates into philosophical consideration. If I have seen a little further it is by standing on the shoulders of Giants.
So if it's (also) meant as a quip, it's a friendly one. And in either case, the saying goes back to the middle ages and was always meant metaphorically.
"But I fully expect that long before I did, he would have discovered the main elements of NKS, and begun to understand their significance."
PS: Please fix the title. The article has it right - it's "Alan".
What are they used for - what problems can they solve that other methods can't?
Not really. They're a fun diversion, and useful for some simulations, but that's about it.
He also - correctly - observes that the explosion in computational power afforded by modern computers make certain scientific investigations possible that were previously infeasible (e.g. the proof of the four-colour theorem relying on exhaustively testing some 1800 possible scenarios, or numerical simulation of some very complex phenomena).
He then combines these two passions of his and asserts that therefore, computation based on simple systems gives insight into the secrets of life, the universe, and everything.
Cellular automata are simulated on regular grids of cells, which gives them anisotropic (direction-dependent) behavior. For example, moving patterns in most automata can only travel in certain preferred directions (like gliders in Conway's game of life). And patterns that can move in multiple directions usually travel with different speeds in each direction.
In the real world, we don't observe any anisotropy in space, so none of the cellular automata I've seen proposed up to this point can model real physics, even in principle.
Lattice gas automata use hexagonal grids instead of square grids to alleviate this problem somewhat, but the anisotropy never really goes away, it's just reduced.
Wolfram doesn't give even a simple example of how two particle-like structures might repel or attract each other in an isotropic fashion in a network system (or any other system in NKS). That doesn't prove it's impossible, but if it is possible neither Wolfram nor anyone else seems to have any idea how to even get started.
But say you solve that problem too -- there are many more problems after that. How do you encode the other properties of a particle like mass, charge, spin and momentum into this pattern? How can patterns attract and repel each other at long distances like real particles do?
These problems are probably all solvable, but my point to the original poster was that it's harder than it seems at first, and it's not something that's amenable to a simple search of the state space of possible automata.
If you are interested in this, go read "Gödel Escher Bach". It brilliantly explores this complexity-from-simplicity theme and the consequences of various viewpoints. E.g. you can easily observe/guess whether someone likes to eat curry; however, deriving this from the atoms making up said person is utterly infeasible.
More fundamentally underlying his advocacy is Wolfram's obsession with the things, which, 30 years on, has not yielded very much. They don't seem to be terribly useful. His wider investigation of the structure of computation is certainly worthwhile, but CAs, at least in the form Wolfram's written his bible about [1], don't seem to be the philosophical revelation he promoted them as.