They’ve got diagrams of OR and AND gates with the crabs.
I feel like they would need a NOT gate to do anything meaningful, which obviously isn’t possible. You can’t have zero crabs going in with crabs coming out. Without a NOT gate I don’t think they can do much in the way of traditional computing - you probably can’t run Doom on any number of crabs (although I’d love to be proven wrong).
From the paper the picture is of an and gate.
https://wpmedia.wolfram.com/uploads/sites/13/2018/02/20-2-2.pdf
They’ve got diagrams of OR and AND gates with the crabs.
I feel like they would need a NOT gate to do anything meaningful, which obviously isn’t possible. You can’t have zero crabs going in with crabs coming out. Without a NOT gate I don’t think they can do much in the way of traditional computing - you probably can’t run Doom on any number of crabs (although I’d love to be proven wrong).