refers to exploratory engineering at the atomic and molecular
level, where the nanometer is a common unit of length. The term
is sometimes used to describe any microscopic technology. Physically,
real nanotechnology relates to sizes of only a few atoms' width.
Implementing nanotechnology in its fullest sense would require
the ability to directly manipulate atoms or molecules via mechanosynthesis.
It is sometimes referred to as Molecular nanotechnology
or MNT to distinguish it from Micro Electro Mechanical Systems
A much more neutral term that does not imply
the hype and speculation that surround this field is "molecular
engineering" - progress towards actual engineering at these
scales is discussed in that article. This article focuses on
the longer-term potential and speculations surrounding 'nanotechnology'
as it was originally conceived.
Ralph Merkle has compared today's chemistry
(in contrast to mechanosynthesis) to an attempt to build interesting
Lego brick constructions while wearing boxing gloves. Because
we currently have no tools that allow us to place a particular
molecule in a particular place (so that it bonds in a predictable
way), we must work with randomly moving molecules. As a result,
when we cause a particular chemical reaction, we frequently
get a mix of several different product species. The reaction
is often followed by a physical filtering process to extract
the species we actually wanted, with the other species discarded
as waste. Nanotechnology could therefore offer much cleaner
manufacturing processes than are available with today's bulk
The first mention of nanotechnology (not
yet using that name) was in a talk given by Richard Feynman
in 1959, entitled There's Plenty of Room at the Bottom.
Feynman suggested a means to develop the ability to manipulate
atoms and molecules directly, by developing a set of one-tenth-scale
machine tools analogous to those found in any machine shop.
These small tools would be used to develop and operate a next
generation of one-hundredth-scale machine tools, and so forth.
As the sizes get smaller, it would be necessary to redesign
some tools because the relative strength of various forces would
change. Gravity would become less important, surface tension
would become more important, van der Waals attraction would
become important, etc. Feynman mentioned these scaling issues
during his talk. The feasibility of his proposal has never been
The term nanotechnology was first
used by K. Eric Drexler in his 1986 book Engines of Creation:
The Coming Era of Nanotechnology.
In the fourth chapter, Drexler introduces
self-replication (see also Von Neumann machine), another powerful
premise of nanotechnology. Cells build copies of themselves
in order to reproduce, and human-designed molecular robots could
do the same thing. If a molecular robot were capable of constructing
copies of itself from basic raw materials (most likely to primarily
be carbon), once the first such robot was constructed any desired
quantity could be obtained quite quickly and for a very low
cost. (Self replication is, of course, not the only way in which
machines can be used to build more machines.)
These same generally capable robots, called
assemblers, could then build more special-purpose objects
that humans would find directly useful: houses, kitchen widgets,
cars, furniture, medical instruments, spaceships, etc. Like
the assemblers themselves, these products would be extremely
cheap by comparison with those produced today. Specifically,
the inputs to any such manufacturing process would be raw materials,
energy, design software, and time. For less speculative discussion
of this potential, see the separate article on the molecular
Another application of nanotechnology is
utility fog, in which a cloud of networked microscopic robots
(simpler than assemblers) changes its shape and properties to
form macroscopic objects and tools in accordance with software
commands. Rather than modify the current practices of consuming
material goods in different forms, utility fog would simply
replace most physical objects.
Whilst progress has been made in producing
ever-smaller computer circuits and nanowires, and manipulating
individual atoms, constructing real nanomachines is currently
well beyond our present capabilities and is widely believed
to be decades away. Critics doubt that controllable self-replicating
nanobots are possible at all, citing the possibility of mutations
removing any control and favouring reproduction of the mutant
pathogenic variations. Advocates counter that bacteria are designed
to mutate, and nanobot mutation can be prevented by common error-correcting
techniques used in computers today. They also note that self-replicating
machines are not a necessary part of a productive nanotechnology.
Research in this area has included the development of simulation
software, such as NanoCAD.
Despite its current early developmental status,
there has been much speculation about the impact of nanotechnology
on economics and law. Some imagine that money would cease to
be of use and taxation would cease to be feasible. Others conjecture
that nanotechnology would elicit a strong public-opinion backlash,
as has occurred recently around genetically modified plants
and the prospect of human cloning. Whatever the exact effects,
nanotechnology is likely to upset existing economic structures,
as it should reduce the scarcity of manufactured goods and make
many more goods (such as food and health aids) manufacturable.
Most futurists and all economists believe
there would still be a need for money, in the form of unforgeable
digital cash. It might be used to buy goods and services that
are unique, or limited within the solar system. These might
include: matter, energy, information, real estate, design services,
entertainment services, legal services, fame, political power,
or the attention of other people to your political/religious/philisophical
message. Beyond that, there is war, even between prosperous
states, and non-economic goals to consider.
Most people believe that virtual reality
will not much reduce interest in obtaining limited resources,
such as a chance to talk to the real president of a major country,
or owning part of the real Jerusalem, or having a famous celebrity
say nice things about you in a digitally-signed document, or
gaining the mining rights to the larger near-earth asteroids.
Demand will always exceed supply for some things, and there
will continue to be a political economy in any case.
Beyond the fantasy scenarios, nanotechnology
has daunting risks. It enables cheaper and more destructive
conventional weapons. Also, nanotechnology permits weapons of
mass destruction that self-replicate, as viruses and cancer
cells do when attacking the human body. There is general agreement
that self-replication should be permitted only very controlled
conditions, if at all.
There is a fear that nanomechanical robots
(nanobots), if designed to self-replicate using naturally occuring
materials (a difficult task), could consume the entire planet
in their hunger for raw materials, or simply crowd out natural
life, out-competing it for energy (as happened historically
when blue-green algae appeared and outcompeted earlier life
forms). This situation is sometimes called the "grey goo" or
"ecophagy" scenario. K. Eric Drexler considers an accidental
"grey goo" scenario extremely unlikely. The "grey goo" scenario
begs the Tree Sap Answer. How likely is it that your car could
spontaneously mutate into a wild car, run off road and live
in the forest off of tree sap?
In light of these dangers, the Foresight
Institute (founded by K. Eric Drexler to prepare for the arrival
of future technologies) has drafted a set of guidelines for
the ethical development of nanotechnology. These include the
banning of self-replicating pseudo-organisms on the Earth's
surface, at least, and possibly other places.
Drexler and others have extended the ideas
of nanotechnology with two more books, Unbounding the Future:
the Nanotechnology Revolution and Nanosystems: Molecular
Machinery, Manufacturing, and Computation. Unbounding
the Future is an easy-to-read book that introduces the
ideas of nanotechnology in a not-too-technical way, and Nanosystems
is an in-depth analysis of nanomachines and molecular manufacturing,
with thorough scientific analyses of their feasibility and performance.
Another notable work in the same vein is Nanomedicine
by Robert Freitas.
Nanotechnology is often poorly understood
by political commentators. In In the Absence of the Sacred:
The Failure of Technology and the Survival of the Indian Nations
(ISBN 0871565099) Jerry Mander uses the term "nano-technology"
based on a telephone call he had with a writer for Mother Jones
magazine. Presumably, Mander believes that MNT would be alienating
to American Indians and other Native Peoples, but in Engines
of Creation: The Coming Era of Nanotechnology. K. Eric
- One test of the freedom a technology offers
is whether it frees people to return to primitive ways of
life. Modern technology fails this test; molecular technology
succeeds. As a test case, imagine returning to a stone-age
style of life—not by simply ignoring molecular technology,
but while using it.
Nanotechnology has also become a prominent
theme in science fiction, for example with the Borg in Star
Trek, Greg Bear's Blood Music, Michael Crichton's Prey,
and Neal Stephenson's more accurate book The Diamond Age.