> how does one voxel communicate to the neighboring voxel what to update without passage through ‘stuff in between’ that doesn’t exist? Heh

That kind of reminds me of the 'aether' that was once hypothesized as a medium of transmission for light and radio waves [0].

Also, voxel's communicating sounds an awful lot like a higher-dimensioned cellular automata.

[0] - https://en.wikipedia.org/wiki/Aether_theories