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Leading nanotech experts put 'grey goo' in perspective

A paper published today in the journal Nanotechnology warns that fear of runaway self-replicating machines diverts attention away from other more serious risks of molecular manufacturing. The paper, “Safe Exponential Manufacturing,” published by the Institute of Physics, was written by Chris Phoenix, Director of Research at the Center for Responsible Nanotechnology (CRN), and Dr. K. Eric Drexler, a pioneering nanotechnology theorist and founder of the Foresight Institute.

Drexler had cautioned against self-replicating machines in his 1986 book Engines of Creation. The idea became known as ‘grey goo’ and inspired a generation of science fiction authors. In this article, Phoenix and Drexler show that nanotechnology-based fabrication can be completely safe from out-of-control replication. However, they warn that for other reasons misuse of molecular manufacturing remains a significant danger.

“So-called grey goo could only be the product of a deliberate and difficult engineering process, not an accident,” said Phoenix. “Far more serious is the possibility that a large-scale and convenient manufacturing capacity could be used to make incredibly powerful non-replicating weapons in unprecedented quantity. This could lead to an unstable arms race and a devastating war. Policy investigation into the effects of advanced nanotechnology should consider this as a primary concern, and runaway replication as a more distant issue.”

Contrary to previous understanding, self-replication is unnecessary for building an efficient and effective molecular manufacturing system. Instead of building lots of tiny, complex, free-floating robots to manufacture products, it will be more practical to use simple robot arms inside desktop-size factories. A robot arm removed from such a factory would be as inert as a light bulb pulled from its socket. The factory as a whole would be no more mobile than a desktop printer and would require a supply of purified raw materials to build anything.

“An obsession with obsolete science-fiction images of swarms of replicating nanobugs has diverted attention from the real issues raised by the coming revolution in molecular nanotechnologies,” said Drexler. “We need to focus on the issues that matter—how to deal with these powerful new capabilities in a competitive world.”

Mike Treder, Executive Director of CRN, said, “We hope that this article will advance the discussion of the actual implications of molecular manufacturing. There is no need for panic, but there are urgent concerns that must be addressed before the technology arrives.”


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