The Dark Secret of Hendrik Schön - questions and answers
What are nanobots?
A nanobot is an advanced electro-mechanical device that functions on a scale measured in nanometres. The thickness of a human hair is roughly 10,000 nanometres. The idea of a nanobot was first proposed by Eric Drexler in the 1980s, and is discussed in his book Engines of Creation. Advanced nanobots could perform computations, sense and respond to environmental stimuli, communicate and cooperate, self-repair, and replicate. The idea is currently purely theoretical. Scientists speculate that the engineering and physical difficulties engendered by building such devices may take 50-100 years to overcome, or may be insurmountable.
Those who propose nanobots suggest they could be used in medicine - machines small enough to travel through the bloodstream and unclog blocked arteries, or even destroy cancerous cells. Or these tiny robots could be used in manufacturing, even to build other tiny robots. Some have suggested military applications – linked robots could scan and map territory beyond the range of satellites, or could even lie dormant and ambush specified targets in huge swarms.
How big are nanobots? (see above)
What is the grey goo problem?
The grey goo problem was first described by Eric Drexler in his 1986 book Engines of Creation. The argument runs like this: if mankind becomes capable of constructing miniature robots that have some way of obtaining power from their environment, and these robots build other robots, using material from the world around them – very soon the entire world will be covered in replicating robots – a ‘grey goo’. Grey goo is a very controversial notion though and most scientists are highly sceptical that this will ever come to pass.
What is Moore’s Law?
Moore’s Law is named after Gordon Moore, one of the co-founders of Intel Corporation. In 1965 Moore noticed that the number of components that make up an integrated circuit had doubled approximately 18 months up to that point. Amazingly, Moore’s Law has been maintained ever since. Every 18 months there has been roughly a doubling in the number of transistors (the basic element of computing) that can be squeezed onto a given area of processor. Today there are roughly 42 million transistors on a Pentium 4 processor.
This phenomenal rate of growth has been achieved by constantly shrinking the size of the transistors themselves. Sooner or later however, scientists speculate that Moore’s Law will meet insurmountable barriers of physics. At the nanometre scale materials become only hundreds of atoms thick, so can behave unpredictably. However, the end of Moore’s Law has been predicted to have arrived several times in the past, and the fact it has been sustained is a testament to the incredible engineering achievements of chip manufacturers.
Why do some speculate that we could lose control of nanobots?
There are two reasons why people might fear the idea of miniature self-controlled robots. The first is their sheer size – an individual nanobot would be invisible to the naked eye. We are all scared by what we can’t see, and there is a fear these robots could easily fall into the wrong hands.
The second fear is of swarms of intelligent nanobots overcoming their inbuilt controls. If nanobots are programmed so that they can learn, and have abilities to sense the world around them, they quickly can build up simple rules about their environment. If millions of these nanobots are linked as a massive network they could gain a kind of swarm intelligence that exceeds our ability to control them. Writers draw analogies with animals that occur in large groups or swarms. For example, each termite may have little individual intelligence, but collectively several thousand termites build a nest of incredible complexity. Simple rules, applied to large numbers of individuals, can achieve spectacular results. So some fear that a swarm of nanobots might learn to outwit the humans that programmed them.
Why do we need nanotechnology?
Nanotechnology is already here. It is simply the ability to do things on the scale of atoms and molecules and exploit the novel properties found at that scale. Computer hard disks have used nanotechnology for years. What is changing is our success in measuring, seeing, predicting and making objects on the nanoscale. Proponents of nanotechnology suggest it will affect almost every aspect of our lives - from the medicines we use, to the power of computers, the energy supplies we require, the food we eat, the cars we drive, the buildings we live in and the clothes we wear.
Nanotechnology should let us make almost every manufactured product faster, lighter, stronger, smarter, safer and cleaner. It is not a single branch of science, but a massive, wide-ranging area of research. Nanotechnology is not just about miniaturizing things. What scientists are taking advantage of is that at the nanoscale different laws of physics come into play, the properties of materials change. Making materials atomically exact radically changes their properties. Unlike normal manufacturing, with nanotechnology it may become possible to design and build objects atom by atom, from the bottom up. There is no waste material, and each device could become incredibly efficient if every single molecule performs a set function.
How did Schön’s papers get past peer review?
The peer review process is not designed to catch fraud. Peer review is a system whereby articles submitted to a journal are sent to professional equals of the principal author to advise them as to whether the material has potential and if so, what further work is needed to make it publishable. A paper is only accepted when the revisions are made to the satisfaction of both editor and referees. A reviewer usually trusts the experimenter to have written down only their exact findings. Schon’s work may have got through this process because of two reasons -
- He worked with obscure materials in experimental set-ups where others may have had little experience.
- His work often was not a huge scientific advance, but a small improvement in a technique or material. He was careful to mostly stay within the boundaries of what was physically possible to achieve.
Several reviewers of Schon’s papers did express doubts about the validity of the work, but he came up with reasonable explanations for discrepancies or modified his findings accordingly.
The doubts about Schon’s work really started when other scientists tried to replicate what he had done. It is likely the misconduct would have been uncovered fairly quickly despite the detective work of Paul McEuen and Lydia Sohn as more and more researchers were unable to get the same results.
How far away is a breakthrough in nanotechnology or an alternative to the silicon chip?
Breakthroughs in nanotechnology are constantly being announced. One of the most exciting areas currently is carbon nanotube research. A nanotube is a hollow graphite cylinder with a diameter of only a few nanometres. They are 10 times as strong as carbon fibres, incredibly light, and have interesting chemical and electrical properties. Progress has been made in using these nanotubes to form parts of electrical circuits.
Chip manufacturers are also looking into ways of extending the life of silicon. There is a theoretical ‘brick wall’, a limit to the smallest size a workable silicon transistor can shrink. Currently experts predict we will hit this wall in about 15 years time (although predictions of the death of silicon in the past have been proven wrong). To continue the exponential trend set by Moore’s Law, manufacturers may start to build chips in three dimensions, or replace silicon dioxide with other materials.
There is a great deal of research looking into entirely new ways of building chips. Some, like Hendrik Schon, are experimenting with organic molecules that could self-assemble into computer circuits. Others are looking into quantum computing, where quantum entanglement could be used to solve problems exponentially faster than any other kind of computer.