Gray goo

From Wise Nano

Gray goo was a risk publicized in Eric Drexler's Engines of Creation. The concern was that an engineered bacteria-like manufacturing system might be able to consume biomass and build more of itself without limit, outcompeting natural life and eventually consuming the biosphere. The expected high performance of nanoscale robotic systems reinforced the scariness of the idea.

Since then, molecular manufacturing has shifted to more purely robotic manufacturing systems requiring purified chemicals, immobile and completely unable to evolve. Unfortunately, the concept of "gray goo" was not left behind in this shift. Chris Phoenix and Eric Drexler recently published a paper in the IoP journal Nanotechnology entitled "Safe Exponential Manufacturing," arguing that diamondoid manufacturing systems would not be capable of free-range self-replication at any time during lab development or use. Furthermore, general-purpose manufacturing from unrefined feedstocks would be hard to do, and any product with this ability would be far less efficient than a non-replicating product built by a separate manufacturing system.

Gray goo is still a theoretical possibility. But both Phoenix (Director of Research of the Center for Responsible Nanotechnology) and Drexler have argued that deliberate misuse of powerful non-replicating products of molecular manufacturing should be a much more urgent concern.