[science4sail]

What do you define as an "artificial physical self-replicating machine"?

A genetically engineered bacterium is a self-replicating machine created via artificial means that exists to effect some purpose in the physical world.

[science4sail]

For that matter, the Earth has already had a grey goo ecological disaster: https://en.wikipedia.org/wiki/Great_Oxidation_Event

[smlckz]

- ''Artificial'': not naturally occuring, also not a "clone"/"fork" of something natural.

- ''Physical'': not software simulation, virtual; "exist" in the same world we live in.

If my original terminology is insufficient or ambiguous, please suggest better terms.