If you have never heard of a Von Neumann machine, its a machine that can build exact replicas of itself. Now in space, this would provide you with the best explorer you could ever want. Send it to a star system, have it build two copies of itself, then send those two to another system to build two more copies each, etc. Recently, a small robot was programmed to build an exact replica of itself and suceeded. The problem is, would there be a risk of "Grey Goo" happening?
risk is in everything. A way to stop the machines from self replicating is to have all the machines be coordinated via a central unit which has capabilities of controlling rate of machine reproduction, as well as ability to stop this.
You could perhaps introduce a programs that limit the amount of replicas each can produce and a liimit to how many generations of machines there are.
Eric Drexler, in Engines of Creation", first brought up the grey goo scenario in reference to nanotech. he has since refined his ideas and no longer see this scenario as necessarily viable. >>Eric Drexler, the “father of nanotechnology”, has revealed his latest views on molecular manufacturing. Writing in Nanotechnology journal, Drexler explains how he now believes that self-replication - the initial source of “grey goo” fears in which nanomachines run amok and overwhelm the world - is not an essential part of the molecular manufacturing process.<< http://nanotechweb.org/articles/society/3/6/1/1
Any self replicating machine has the possibility of introducing entropy into it's process of self replication. Eventually it would be like when you make a xerox copy of a xerox copy of a xerox copy........ etc. You'd only get so many high quality self replications out of it.
Not exactly. They gather materiaels at a site ( say an asteroid field), then gather fuel ( harvesting from a gas giant like Jupiter ). Each time, you get a high quality replica. You could also make beserkers which are designed to wipe out civilzation when they encounter it instead of making peace with it.
Von Neumann is usually attributed to computer architecture. I don't think grey goo is feasible - surely it'd have already happened? (Micro organisms)