I think imgur might show things differently on different devices, but on PC the description mentions it: > Grey goo is molecular robots self-replicating endles

I think imgur might show things differently on different devices, but on PC the description mentions it: > Grey goo is molecular robots self-replicating endlessly. This is the more interesting Ackermann goo made from molecular computing of Ackermann(4,4). The idea is: if universal molecular computation is possible then by making a molecule which computes Ackermann(4,4), which is huge, we obtain a goo far more interesting than one made of many replica of one molecule.