One of the novels I remember reading where best developed the implications of nano tech advances (even wars occurred far from our sight, in large dark clouds where rivals battled dumb nano technological devices) was The Diamond Age (1995), by Neal Stephenson .
However, the threats of nanotechnology do not belong exclusively to the realm of science fiction.
The nano-sized machines have roughly less than a human hair, and they can replicate themselves on the fly. imagine that a detachment of nanorobots launched on a oil spill in order to eliminate it .One of the nanorobots suffers a programming error and no longer feeds only oil, but anything that contains carbon.
That is, not only oil but consume any living organism. Robots multiply rapidly and, before we know it,have devoured all life on Earth .
It’s a similar argument to the one presented in the novel Prey , of Michael Crichton (same Jurassic Park ), but it is plausible. So much so that the British astronomer and former presidents of the Royal Society Martin Rees has suggested that this scenario could be a potential cause of the extinction of humanity .
Eric Drexler who was first introduced to the world because of self-replicating robots in his 1986 book Nanotechnology: the emergence of maqinas added :
Imagine such a replicator floating in a bottle of chemicals, making copies of itself … the first replicator weapon a copy in one thousand seconds, the two replicators resulting construct two more in the next thousand seconds, the four build four more, then eight, eight more. Ten hours later, we would have already thirty-six new replicators, but over sixty-eight billion. In less than a day, together weigh a ton, in less than two days, rather than the Earth, and in just four hours, would exceed the mass of the Sun and all the planets together … if the bottle of chemicals had not exhausted much earlier.
Fortunately, creating self-replicating robots is not yet possible. Writing in Nature Materials , Philip Ball believes that this idea is alarmist, replicating the real threats are, perhaps, a few smallpox.
The closest thing to replicators robots are machines built from scratch : as tiny nickel propeller had inserted a researcher at Cornell University in New York to a biological version of a fuel-powered engine that provides power to humans , a molecule called ATP .
In any case, the nanorobots achieved by Drexler presented, does not seem that the threat is so terrible, as explained Alok Jhar in his book 50 ways to destroy the world :
Any device able to replicate with the speed required by the scenario proposed by Drexler need energy and produce so much heat that it would be easy to detect by inspection bodies, which could well cope with the threat. On the other hand, if nano machines were made with minerals containing aluminum, titanium or boron, then living organisms would be safe from danger, as these metals are millions of times more abundant in the earth’s crust in living organisms. Instead of killing us, the machines would be devoted to dig the planet.