There's Plenty of Room at the Bottom

"There's Plenty of Room at the Bottom" was a lecture given by physicist Richard Feynman at an American Physical Society meeting at Caltech on December 29, 1959.^[1] Feynman considered the possibility of direct manipulation of individual atoms as a more powerful form of synthetic chemistry than those used at the time. The talk went unnoticed and it didn't inspire the conceptual beginnings of the field. In the 1990s it was rediscovered and publicised as a seminal event in the field, probably to boost the history of nanotechnology with Feynman's reputation.

Conception

Feynman considered a number of interesting ramifications of a general ability to manipulate matter on an atomic scale. He was particularly interested in the possibilities of denser computer circuitry, and microscopes that could see things much smaller than is possible with scanning electron microscopes. These ideas were later realized by the use of the scanning tunneling microscope, the atomic force microscope and other examples of scanning probe microscopy and storage systems such as Millipede, created by researchers at IBM.

Feynman also suggested that it should be possible, in principle, to make nanoscale machines that "arrange the atoms the way we want", and do chemical synthesis by mechanical manipulation.

He also presented the possibility of "swallowing the doctor," an idea that he credited in the essay to his friend and graduate student Albert Hibbs. This concept involved building a tiny, swallowable surgical robot.

As a thought experiment he proposed developing a set of one-quarter-scale manipulator hands slaved to the operator's hands to build one-quarter scale machine tools analogous to those found in any machine shop. This set of small tools would then be used by the small hands to build and operate ten sets of one-sixteenth-scale hands and tools, and so forth, culminating in perhaps a billion tiny factories to achieve massively parallel operations. He uses the analogy of a pantograph as a way of scaling down items. This idea was anticipated in part, down to the microscale, by science fiction author Robert A. Heinlein in his 1942 story Waldo.^[2][3] As the sizes got smaller, one would have to redesign some tools, because the relative strength of various forces would change. Although gravity would become unimportant, surface tension would become more important, Van der Waals attraction would become important, etc. Feynman mentioned these scaling issues during his talk. Nobody has yet attempted to implement this thought experiment, although it has been noted that some types of biological enzymes and enzyme complexes (especially ribosomes) function chemically in a way close to Feynman's vision. He also mentioned in his lecture that it might be better eventually to use glass or plastic instead of silicon and other metals, because their greater uniformity would avoid problems in the very small scale. It is an interesting fact that there are now active elements in both glass and plastic. In glass, because fiber optic cables amplify the light pulses at regular distances, using doped glass.^[4] Plastic logic has also become a reality.^[5]

Challenges

At the meeting, Feynman concluded his talk with two challenges, and he offered a prize of $1000 for the first individuals to solve each one. The first challenge involved the construction of a tiny motor, which, to Feynman's surprise, was achieved by November 1960 by William McLellan, a meticulous craftsman, using conventional tools. The motor met the conditions, but did not advance the art. The second challenge involved the possibility of scaling down letters small enough so as to be able to fit the entire Encyclopædia Britannica on the head of a pin, by writing the information from a book page on a surface 1/25,000 smaller in linear scale. In 1985, Tom Newman, a Stanford graduate student, successfully reduced the first paragraph of A Tale of Two Cities by 1/25,000, and collected the second Feynman prize.^[6][7]

Impact

K. Eric Drexler later took the Feynman concept of a billion tiny factories and added the idea that they could make more copies of themselves, via computer control instead of control by a human operator, in his 1986 book Engines of Creation: The Coming Era of Nanotechnology.

After Feynman's death, scholars studying the historical development of nanotechnology have concluded that his actual role in catalyzing nanotechnology research was limited, based on recollections from many of the people active in the nascent field in the 1980s and 1990s. Chris Toumey, a cultural anthropologist at the University of South Carolina, has reconstructed the history of the publication and republication of Feynman’s talk, along with the record of citations to “Plenty of Room” in the scientific literature.^[8][9] In Toumey's 2008 article, "Reading Feynman into Nanotechnology", he found 11 versions of the publication of “Plenty of Room", plus two instances of a closely related talk by Feynman, “Infinitesimal Machinery,” which Feynman called “Plenty of Room, Revisited.” Also in Toumey’s references are videotapes of that second talk.

Toumey found that the published versions of Feynman’s talk had a negligible influence in the twenty years after it was first published, as measured by citations in the scientific literature, and not much more influence in the decade after the Scanning Tunneling Microscope was invented in 1981. Subsequently, interest in “Plenty of Room” in the scientific literature greatly increased in the early 1990s. This is probably because the term “nanotechnology” gained serious attention just before that time, following its use by Drexler in his 1986 book, Engines of Creation: The Coming Era of Nanotechnology, which cited Feynman, and in a cover article headlined "Nanotechnology", published later that year in a mass-circulation science-oriented magazine, OMNI.^[10][11] The journal Nanotechnology was launched in 1989; the famous Eigler-Schweizer experiment, precisely manipulating 35 xenon atoms, was published in Nature in April 1990; and Science had a special issue on nanotechnology in November 1991. These and other developments hint that the retroactive rediscovery of Feynman’s “Plenty of Room” gave nanotechnology a packaged history that provided an early date of December 1959, plus a connection to the charisma and genius of Richard Feynman.

Toumey’s analysis also includes comments from distinguished scientists in nanotechnology who say that “Plenty of Room” did not influence their early work, and in fact most of them had not read it until a later date.

Feynman's stature as a Nobel laureate and as an iconic figure in 20th century science surely helped advocates of nanotechnology and provided a valuable intellectual link to the past.^[2] More concretely, his stature and concept of atomically precise fabrication played a role in securing funding for nanotechnology research, illustrated by President Clinton January 2000 speech calling for a Federal program:

My budget supports a major new National Nanotechnology Initiative, worth $500 million. Caltech is no stranger to the idea of nanotechnology the ability to manipulate matter at the atomic and molecular level. Over 40 years ago, Caltech's own Richard Feynman asked, "What would happen if we could arrange the atoms one by one the way we want them?"^[12]

While the version of the Nanotechnology Research and Development Act that was passed by the House in May 2003 called for a study of the technical feasibility of molecular manufacturing, this study was removed to safeguard funding of less controversial research before the Act was passed by the Senate and finally signed into law by President Bush on December 3, 2003.^[13]

Fiction byproducts

• In "The Tree of Time", a short story published in 1964, Damon Knight uses the idea of a barrier that has to be constructed atom by atom (a time barrier, in the story).

See also

• Foresight Nanotech Institute Feynman Prize

References

External links

• Feynman's classic 1959 talk: There's Plenty of Room at the Bottom