Drexler–Smalley debate on molecular nanotechnology

[3] K. Eric Drexler is generally considered to have written the first scholarly paper on the topic of nanotechnology,[4][5] and was a key figure in popularizing these concepts through several publications and advocacy work.

[4] Richard E. Smalley, a chemist at Rice University, was best known as a co-discoverer of the C60 form of carbon known as buckminsterfullerene in 1985, along with Harry Kroto, Robert Curl, James Heath, and Sean O'Brien.

The study and application of fullerenes forms a significant part of the fields of nanomaterials and nanoelectronics, and Smalley, Kroto, and Curl were awarded the 1996 Nobel Prize in Chemistry for their discovery.

[10] Smalley opened by comparing a chemical reaction to an intricate dance of atoms: When a boy and a girl fall in love, it is often said that the chemistry between them is good.

In a chemical reaction between two 'consenting' molecules, bonds form between some of the atoms in what is usually a complex dance involving motion in multiple dimensions.... And if the chemistry is really, really good, the molecules that do react will all produce the exact product required.He referenced the idea of a molecular assembler, a nanorobot capable of manipulating individual atoms to build a desired product, posing the question of how long it would take such an assembler to produce a meaningful amount of material.

Drexler responded by publishing a rebuttal later in 2001 through the Institute for Molecular Manufacturing, which was co-authored with others including Robert Freitas, J. Storrs Hall, and Ralph Merkle.

They cited as evidence experimental and theoretical results indicating that using scanning tunneling microscope (STM) tips and related technologies could be used as a reactive structure for positional control and for interaction with surface-bound molecules.

He then agreed that something like an enzyme or ribosome would be capable of precise chemistry, but asked how the nanorobot would be able to obtain, control, and repair such an enzyme, and noted the incompatibility of many reactions with water-based biological systems, stating that "biology is wonderous in the vast diversity of what it can build, but it can't make a crystal of silicon, or steel, or copper, or aluminum, or titanium, or virtually any of the key materials on which modern technology is built."

He characterized the challenges as being that of systems engineering rather than solely chemistry, and referred Smalley to Nanosystems, with its vision of mechanical control of chemical reactions with no enzymes and no reliance on solvents or thermal motion.

Transition-state theory indicates that, for suitably chosen reactants, positional control will enable synthetic steps at megahertz frequencies with the reliability of digital switching operations in a computer.

I hope you will agree that the actual physical principles of molecular manufacturing are sound and quite unlike the various notions, many widespread in the press, that you have correctly rejected.

I invite you to join me and others in the call to augment today's nanoscale research with a systems engineering effort aimed at achieving the grand vision articulated by Richard Feynman.Smalley began his concluding letter: I see you have now walked out of the room where I had led you to talk about real chemistry, and you are now back in your mechanical world.

Lastly, Smalley recounted his recent experience reading essays written by middle and high school students after an outreach visit, saying that nearly half of them thought that self-replicating nanorobots were possible and that most were worried about the results of them spreading across the world.

"[9] Zyvex founder James von Ehr remarked that "Eric [Drexler] didn't do himself any favors by getting into a pissing match with a Nobel-prize winner.

Steven A. Edwards in The Nanotech Pioneers noted that the ambiguity of the specifications and even definition of a molecular assembler makes an evaluation of the argument difficult and minimizes its scientific implications.

He quoted experimental results on enzyme function in nonaqueous solutions, and pointed out that modern non-biological technology such as airplanes and computers have exceeded the capabilities of natural biological systems.

He also noted that "earlier critics also expressed skepticism that either worldwide communication networks or software viruses that would spread across them were feasible... [but today] we are obtaining far more gain than harm from this latest example of intertwined promise and peril.

Political blogger Glenn Reynolds stated that "the business community is afraid that advanced nanotechnology just seems too, well, spooky—and worse, that discussions of potentially spooky implications will lead to public fears that might get into the way of bringing products to market.

"[17] Lawrence Lessig criticized the scientific establishment, represented by Smalley, for arguing that "if so-called dangerous nanotech can be relegated to summer sci-fi movies and forgotten after Labor Day, then serious work can continue, supported by billion-dollar funding and uninhibited by the idiocy that buries, for example, stem cell research.

The debate between K. Eric Drexler and Richard Smalley on the feasibility of molecular assemblers began in 2001 and concluded in a cover story in Chemical & Engineering News in 2003.
K. Eric Drexler developed and popularized the concept of nanotechnology and founded the field of molecular nanotechnology .
Smalley's 2001 Scientific American article doubting the feasibility of molecular assemblers led to a rebuttal by Drexler and his colleagues.
A depiction of a putative technomimetic molecular planetary gear set. Smalley questioned whether devices like these could be constructed using an enzyme -like mechanical process, either in an aqueous solution or with some other chemistry, and whether such devices would be operational at all.