Universal Constructor: Theory, Principles, and Practice
by Wayne Yin
...and thus arose the need for a more generalized theory encompassing a "Universal Constructor" (UC) that would be able to handle such arbitrarily complex nanoscale design problems. Unlike the simple atom by atom nanotech constructors common today, a UC would combine millions upon millions of atoms in a parallel process that could produce materials or mechanisms of unmatched intricacy on a scale currently not possible even with the best nanoscale foundry.
One of the most obvious applications of a UC -- if its construction were ever practical -- would be the genetic manipulation of lifeforms at the atomic level to cure disease, correct congenial defects, or expand their capabilities in beneficial ways. Theoretically, if an "intelligent," real-time control program were developed for the UC, then autonomous, artificial nanoscale organisms could be assembled. Careful design could create organisms that might actually exist in "symbiosis" with other life.
However, a UC also creates the tangible threat of a "grey goo" scenario: the design of an organism that is so evolutionarily advanced as to overwhelm the current ecosystem...