Nanotechnology and Artificial Life. Intertwined from the beginning. Living systems are frequently held up as proof that nano-machines are feasible.

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1 Nanotechnology and Artificial Life Intertwined from the beginning Living systems are frequently held up as proof that nano-machines are feasible. Nano-machines are difficult to fabricate in large quantities, leading to a biomimetic approach: design them to assemble each other. Will they be alive? What is life? A Geneology of Nanotechnology Erwin Schrödinger: Quantum Physicist 1945: What is Life? Can life be explained by Chemistry and Physics? Hypothesized a giant molecule of heredity that contains a codescript that determines the entire future development of the organism. Foreshadows DNA as the instruction set of the organism. (Watson & Crick not until 1953) Can life be explained using scientific principles? 1

2 John von Neumann: mathematician 1945: Introduced concept of cellular automaton Automaton: a collection of connected elements computing and transmitting information. Can an automaton be constructed that is capable of reproducing itself? Can life be constructed using technology? Conway s Game of Life : A simple Cellular Automaton Life was invented by mathematician John Conway in Rules of the game: A dead cell with exactly three live neighbors becomes a live cell (birth). A live cell with two or three live neighbors stays alive (survival). All other cases, a cell dies or remains dead (overcrowding or loneliness) X X 2

3 Richard Feynman The greatest American Physicist 1959: There s Plenty of Room at the Bottom After-dinner speech at the annual meeting of the American Physical Society Each generation of machine tools will craft another generation with finer capabilities. (Follows closely upon invention of µfabrication.) It will eventually result in atomically precise machinery. Offered $1000 rewards for: 1. Electric motor smaller than 0.4 mm (claimed the same year) 2. Book page with a font size of ~100 nm (claimed in 1985) K. Eric Drexler: Prophet of Nanotechnology? 1981: Molecular Engineering Books: Engines of Creation Unbounding the Future available on the WWW If nature can produce molecular machines (i.e. proteins) it is unreasonable to assume that they cannot be created synthetically. Nature s molecular machines are capable of creating other molecular machines. Should also be true of synthetic nanomachines. Controversial figure: lacks real scientific credibility and has very dogmatic views about how nanomachines should be constructed. diamondoid machine parts built atom-by-atom universal assembler 3

4 Contemporary Visions of the Nanotech Future Conrad Schneiker: (1) Start with a natural life form and gradually transform it into a totally artificial life form by using molecule-by-molecule replacement. (2) Develop a hybrid living system that incorporates some nanotechnology for computing functions and some microtechnology for artificial replication. K. Eric Drexler: Molecular nanotechnology: Thorough, inexpensive control of the structure of matter based on molecule-by-molecule control of products and byproducts of molecular manufacturing." The Universal Assembler Second-generation machines will be able to use as "tools" almost any of the reactive molecules used by chemists - but they will wield them with the precision of programmed machines. They will be able to bond atoms together in virtually any stable pattern, adding a few at a time to the surface of a workpiece until a complex structure is complete. Think of such nanomachines as assemblers. Machines must be self-replicating for low costs. BTW: Drexler is seen as a bit of a dilettante in some circles. Science is unsophisticated, thinking is naïve. 4

5 What is Life? No universally accepted answer to this question. Not enough to ask if a given individual is alive, the question refers to an entire system of life (avoids mule problem). Two basic principles often mentioned: (1) Self-replication; heritable code for organism development (2) Ability to adapt/evolve (Darwinian or otherwise) These principles are also designed to explain how life could develop. Artificial life gives new meaning to the word Creationism Would Darwinian evolution be the only way for created organisms to adapt? J. Doyne Farmer (Physicist, Los Alamos Nat l Lab): In the next 50 years, a new class of organisms will emerge They will be artificial in the sense that they are designed by humans, but they will reproduce, evolve, etc. The subsequent pace of evolutionary change will be extremely rapid. Impact on humanity will be enormous: greater than industrial revolution, nuclear weapons, environmental pollution, etc. We must take steps now to shape the emergence of artificial organisms... 5

6 Ray Kurzweil (expert on artificial intelligence) digital sampling keyboard reading machine speech recognition Author of The Age of Spiritual Machines Optimistically foresees coexistence between humans and machines that will vastly improve the quality of our lives and make us nearly immortal. Bill Joy, cofounder and Chief Scientist of Sun Microsystems vs. Emphasizes the dangers of self-replicating technology. Should we do it? Bill Joy, cofounder and Chief Scientist of Sun Microsystems in Wired Magazine, April 2000 Why the future doesn't need us The 21st-century technologies - genetics, nanotechnology, and robotics (GNR) - are so powerful that they can spawn whole new classes of accidents and abuses... I think it is no exaggeration to say we are on the cusp of the further perfection of extreme evil... It is most of all the power of destructive self-replication in GNR that should give us pause. (evolve to take over biosphere, etc.) These technologies are too powerful to be shielded against... even if it were possible to implement defensive shields, the side effects of their development would be at least as dangerous as the technologies we are trying to protect against. With the prospect of human-level computing power in about 30 years, a new idea suggests itself: that I may be working to create tools which will enable the construction of the technology that may replace our species. The only realistic alternative I see is relinquishment: to limit development of the technologies that are too dangerous, by limiting our pursuit of certain kinds of knowledge. 6

7 Ray Kurzweil responds (expert on artificial intelligence) Author of The Age of Spiritual Machines Software viruses, although not very intelligent, are self-replicating as well as being potentially destructive. Bioengineered biological viruses are not far behind. As for nanotechnology-based self-replication the consensus is this will be feasible in the 2020s, if not sooner. However, I do reject Joy's call for relinquishment of broad areas of technology (such as nanotechnology)... The continued opportunity to alleviate human distress is one important motivation for continuing technological advancement. Also compelling are the already apparent economic gains, which will continue to hasten in the decades ahead. Forgoing fields such as nanotechnology is untenable. Nanotechnology is simply the inevitable end result of a persistent trend toward miniaturization that pervades all of technology Furthermore, abandonment of broad areas of technology will only push them underground, where development would continue unimpeded by ethics and regulation. In such a situation, it would be the less stable, less responsible practitioners (for example, the terrorists) who would have all the expertise. Trying to halt progress may not be realistic, but there s no question that these issues are important to think about, so... Why are scientists/engineers the only ones discussing this? No one else knows about it. No one else believes it will happen. If the past is any indication, the discussion in society at large will start only after it is late in the game (as for human cloning). 7