SOME OF THE most compelling arguments against the likelihood of nanotechnology reaching the potential of atom-by-atom construction are provided by Richard Smalley.

In his essay, Of Chemistry, Love and Nanorobots, Smalley describes two fundamental problems and the basic difficulties.

Atoms are tiny and move in a circumscribed way. The electronic glue that holds them to one another is not local to each bond but rather is sensitive to the exact position and identity of all atoms is the near vicinity. So when the nanomanipulator arm of a nanorobot goes to pick up an atom and move into place, there is a fundamental problem. The manipulator has to control not only this new atom, but also all of the atoms in the region. Even with an additional manipulator arm for each atom, there are difficulties.

Known Problems

First is the problem of ‘fat fingers.’ Because the fingers of the manipulator arm must themselves be made out of atoms, they have a certain irreducible size. There is just not enough room in the region to accommodate all the fingers of all the manipulators necessary to have complete control.

The second problem is that the fingers of the manipulators are also too‘sticky.’ The atoms of the manipulator hands will adhere to the atom that is being moved. So it will often be impossible to release this miniscule building block in precisely the right spot.

There is also the basic problem of speed in the replicating technologies. Estimates by some say that nanorobots or assemblers would not be able to make any macroscopic matter within millions of years of work. The timelines are however quickly reduced by assuming that the principal reproduction activity in the earliest stages is to replicate assemblers themselves, prior to trying to build other matter. Therefore the production abilities will grow exponentially.

The Institute of Molecular Manufacturing has a rebuttal to Smalley’s arguments posted on their web site.