Gray goo

The term was first used by molecular nanotechnology pioneer K. Eric Drexler in Engines of Creation (1986). In Chapter 4, Engines Of Abundance, Drexler illustrates both exponential growth and inherent limits (not gray goo) by describing "dry" nanomachines that can function only if given special raw materials: According to Drexler, the term was popularized by an article in science fiction magazine Omni, which also popularized the term "nanotechnology" in the same issue. Drexler says arms control is a far greater issue than gray goo "nanobugs". Drexler describes gray goo in Chapter 11 of Engines of Creation: Drexler notes that the geometric growth made possible by self-replication is inherently limited by the availability of suitable raw materials. Drexler used the term "gray goo" not to indicate color or texture, but to emphasize the difference between "superiority" in terms of human values and "superiority" in terms of competitive success: Bill Joy, one of the founders of Sun Microsystems, discussed some of the problems with pursuing this technology in his now-famous 2000 article in Wired magazine, titled "Why The Future Doesn't Need Us". In direct response to Joy's concerns, the first quantitative technical analysis of the ecophagy scenario was published in 2000 by nanomedicine pioneer Robert Freitas. ==Risks and precautions==

Drexler more recently conceded that there is no need to build anything that even resembles a potential runaway replicator. This would avoid the problem entirely. In a paper in the journal Nanotechnology, he argues that self-replicating machines are needlessly complex and inefficient. His 1992 technical book on advanced nanotechnologies Nanosystems: Molecular Machinery, Manufacturing, and Computation describes manufacturing systems that are desktop-scale factories with specialized machines in fixed locations and conveyor belts to move parts from place to place. None of these measures would prevent a party from creating a weaponized gray goo, were such a thing possible. King Charles III (then Prince of Wales) called upon the British Royal Society to investigate the "enormous environmental and social risks" of nanotechnology in a planned report, leading to much media commentary on gray goo. The Royal Society's report on nanoscience was released on 29 July 2004, and declared the possibility of self-replicating machines to lie too far in the future to be of concern to regulators. More recent analysis in the paper titled Safe Exponential Manufacturing from the Institute of Physics (co-written by Chris Phoenix, Director of Research of the Center for Responsible Nanotechnology, and Eric Drexler), shows that the danger of gray goo is far less likely than originally thought. However, other long-term major risks to society and the environment from nanotechnology have been identified. The Foresight Institute also recommended embedding controls in the molecular machines. These controls would be able to prevent anyone from purposely abusing nanotechnology, and therefore avoid the gray goo scenario. ==Ethics and chaos==

Gray goo is a useful construct for considering low-probability, high-impact outcomes from emerging technologies. Thus, it is a useful tool in the ethics of technology. Daniel A. Vallero applied it as a worst-case scenario thought experiment for technologists contemplating possible risks from advancing a technology. This requires that a decision tree or event tree include even extremely low probability events if such events may have an extremely negative and irreversible consequence, i.e. application of the precautionary principle. Dianne Irving admonishes that "any error in science will have a rippling effect". Vallero adapted this reference to chaos theory to emerging technologies, wherein slight permutations of initial conditions can lead to unforeseen and profoundly negative downstream effects, for which the technologist and the new technology's proponents must be held accountable. == In popular culture ==

• An early exploration of a concept similar to gray goo appears in Stanisław Lem's 1964 novel The Invincible. The story features a planet, Regis III, that is dominated by an ecosystem of self-replicating micro-robots. These machines, having undergone a form of mechanical evolution ("necroevolution"), can form vast swarms that act as a collective intelligence, effectively consuming or neutralizing any threat. This depiction of an out-of-control, evolving, and ecologically dominant swarm of machines predates the coining of the term "gray goo" by over two decades. • Grey goo is the basis for "Benderama", an episode of the animated science fiction sitcom Futurama. In this episode, Bender creates smaller copies of himself to accomplish mundane tasks, which quickly spirals out of control as those copies begin replicating themselves, eventually reaching a stage where the copies are small enough to manipulate matter at the subatomic level. • The Horizon video game series is set in the post-apocalyptic aftermath of a grey goo scenario, in which a self-replicating swarm of insectoid robots consumes the Earth's biosphere, rendering all life on the planet extinct. Humanity survives only through an automated terraforming system that revives the species centuries later, with people reduced to living in scattered, primitive tribes. • The plot of the novel Prey by Michael Crichton centers around self-replicating nanobots, which the protagonist attempts to stop before they evolve beyond control. • The video game series Tasty Planet revolves around nanotechnology designed as a cleaning product, which begins to self-replicate and consume everything on the planet. • The 1985 science fiction novel Blood Music features biological computers created from lymphocyte cells. Smuggled out of a laboratory, the cells multiply and evolve rapidly, eventually assimilating much of the biosphere of North America. • The Sonic the Hedgehog comic series included a 21-issue story arc known as the "Metal Virus Saga". The Metal Virus is depicted as a grey goo scenario that converts all organic life into machines. It replicates and mutates like a virus, turning sentient beings into zombie-like robots who spread the infection by touch. • The incremental web game Universal Paperclips features an AI whose sole objective is to create more paperclips, ultimately converting all matter in the universe into paperclips. == See also ==