ABSTRACT
Toolmaking has always differentiated our species from all others on Earth. Aerodynamically correct wooden spears were carved by archaic Homo sapiens close to 400,000 years ago. Man builds things consistent with his size, typically in the range of two orders of magnitude larger or smaller than himself, as indicated in Figure 1.1. Though the extremes of length-scale are outside the range of this figure, man, at slightly more than 100 m, amazingly fits right in the middle of the smallest subatomic particle, which is
approximately 1026 m, and the extent of the observable universe, which is of the order of 1026 m (15 billion light years); neither geocentric nor heliocentric, but rather egocentric universe. But humans have always striven to explore, build, and control the extremes of length and time scales. In the voyages to Lilliput and Brobdingnag of Gulliver’s Travels, Jonathan Swift (1726) speculates on the remarkable possibilities which diminution or magnification of physical dimensions provides.1 The Great Pyramid of Khufu was originally 147 m high when completed around 2600 B.C., while the Empire State Building constructed in 1931 is presently — after the addition of a television antenna mast in 1950 — 449 m high. At the other end of the spectrum of manmade artifacts, a dime is slightly less than 2 cm in diameter. Watchmakers have practiced the art of miniaturization since the 13th century. The invention of the microscope in the 17th century opened the way for direct observation of microbes and plant and animal cells. Smaller things were manmade in the latter half of the 20th century. The transistor — invented in 1947 — in today’s integrated circuits has a size2 of 0.18 micron (180 nanometers) in production and approaches 10 nm in research laboratories using electron beams. But what about the miniaturization of mechanical parts — machines — envisioned by Feynman (1961) in his legendary speech quoted above?
