Stephen's work is intriguing. He wants a model to simulate space, time, matter and energy. Some desirable properties of such a system, from a layman perspective:

1. The model must be fundamentally simple.

2. The model must be able to produce 'interesting' behaviors somehow.

3. The model must exhibit very puzzling behaviors like 'speed of light is a constant', 'space dilation' or 'quantum superposition'.

He observes that extremely simple rewrite systems, like the infamous rule 30, satisfy 1 and 2, under a provable universality result: all 'interesting' behaviors are Turing equivalent. He then observes that the succession of states of the system could be observed as 'time', that having the fundamental simulation substrate create new nodes on the fly could be observed as 'space dilation', that the speed of generating new nodes is a limiting factor in the same way the speed of light is and that having alternate rules applicable in a given configurations could be observed as 'superposition'. This sounds promising. Let's work out the details. To my layman understanding, it's a fundamentally different approach than what physicists have been doing, extremely successfully, in the past 100+ years.

So far, he's empty handed, and very far from concrete results. He's pioneering the exploration of this space by building the first generation of programming languages, the machine code. Maybe 50 later, someone will build ZFS / explain the '3 but not 4 particle generations', using ML to express their thought process.

He's put some thought in attempting to bridge graph rewrite systems to the Universe's behavior. No measurable results, but no [layman's] obvious way to refute either. https://www.wolframphysics.org/technical-introduction/potent...