Self-replication is the key overlap between von Neumann probes and the Machine described here.
A fully self-replicating machine requires these processes:
- collect raw resources
- process raw resources into components*
- assemble components into a new Machine
- copy instructions to new Machine
- start the new Machine
Of these, 4. and 5. are relatively trivial, while 1. is very environment-specific. The interesting questions are:
A. What are the minimum component types necessary to build a self-replicating machine?
B. How can these components be constructed from the availale raw materials?
A and B feed into each other, as more complex components (say, integrated circuits) require more complex refining techniques, which in turn may require more complex components.
I hypothesize that there are actually very few core components (provided speed of reproduction is not a priority):
- solenoid (for relay-based memory)
- conductive/structural material
- insulating/structural material
Anyone have any other thoughts on minimal components for a self-replicating machine?