Three massive scientific waves are gathering momentum as we approach the end of the 20th century. These waves are set to transform our lives in the 21st century to a far greater extent than our parents’ and grandparents’ lives were changed by advances made during this century. Nanoscale science, information science and molecular biology are all rapidly developing into engineering disciplines, and each will be responsible for the start of at least one major industrial revolution during the next 20 years.

The fact that all these revolutionary changes will occur simultaneously is unprecedented in human history. The technologies that will arise will also interact with each other to create entirely new fields of study, but the most fruitful territories for intellectual exploration and economic development will occur at the areas of overlap.

Nanometre-scale logic gates can now be fabricated thanks to advances in both nanoscale and information sciences. Meanwhile, biologists are beginning to use computational methods – so-called bio-informatics – to analyse the wealth of data from gene-sequencing projects to further advance our understanding of fundamental biology. Many people are at least aware of the remarkable advances being made in molecular biology, but the revolutions in information and nanoscale sciences are at least as profound, and are occurring in physics-based disciplines.

Towards the infinitesimal

Nanoscale science involves the study, understanding and control of matter at the atomic level. In the late 1950s only the Nobel prize winning physicist Richard Feynman truly understood that it would be possible to observe and manipulate individual atoms. Today hundreds of laboratories all over the world routinely use the scanning tunnelling microscope – which was invented in the early 1980s by Gerd Binning and Heinrich Rohrer at IBM’s Research Laboratory near Zurich – to obtain topographic maps of material surfaces in which it is possible to identify individual atoms. The beautiful pictures that have appeared in Physics World and elsewhere over the years have shown that it is even possible to build structures and spell out words by pushing individual atoms around on a surface.

In the next century “self-assembly” techniques will be the basis for manufacturing a wide range of objects, from electronic circuits to automobile tyres. In our laboratory at Hewlett Packard, we can create designer structures such as the nanoscale pyramid shown above. The base of the pyramid is just 10 nm wide. This pyramid literally assembled itself from a collection of germanium atoms deposited onto a silicon surface due to the collective forces that bind the atoms to each other. In fact it was one of over a billion similar structures that formed simultaneously on a 0.1 cm² sample within a few seconds.

Many research groups worldwide are working hard to turn nanoscience into a technology. One goal is to build electronic circuits from vast numbers of self-assembled components. A potential advantage of such chemical self-assembly is that the cost of building electronic circuits will be perhaps a thousand times less than it is with existing silicon technology.

The integrated circuits of the future may look a lot more like photographic film than silicon chips, because they will be deposited onto flexible plastic substrates using a chemical bath. The individual components will be molecular switches and wires made from carbon nanotubes, each one containing specific chemical groups that will determine where it attaches to the substrate. Because they contain nanometre-scale objects, circuits built by self-assembly will have a much higher density of components and will be much faster than anything that can be built by current lithographic processes.

However, the basic architecture of these circuits will have to be able to compensate for wiring mistakes and nonfunctional devices because chemical processes are governed by statistics, and this makes it impossible to create perfect systems at a finite temperature. Such defect-tolerant circuitry could also be so cheap to manufacture that it would essentially be free, at which time hardware and software will merge to become the same thing. In this scenario, the programming of the circuits – in other words the product of human creativity – becomes the most valuable component of an electronic device.

The information revolution

In the past 20 years, physicists have realized that information is a physical entity and is subject to the same laws that govern the material universe. Once again, Feynman was one of the pioneers in this area, and his understanding has led to the exciting developments in quantum computing, quantum communications and quantum measurement that have been reported in both the technical and popular press recently (see Physics World March 1998).

Information science has also improved astronomers’ understanding of such exotic phenomena as black holes and the eventual fate of the universe through gedanken experiments that trace what happens when information is swallowed by a black hole. It is possible that new insights into a grand unified theory could come from the study of the quantum mechanical and relativistic implications of information, rather than by smashing particles together at ever higher energies. For example, theoretical analyses of quantum teleportation or non-demolition measurements of a quantum state at or across the edge of a black hole could provide crucial insights into quantum gravitation.

An improved understanding of the physical nature of information should also make it easier to collect, store, process and retrieve information that is really important. Some people complain about information overload, but perhaps we suffer from just the opposite. People are actually inundated with raw unsorted data, which by itself is quite useless and requires huge amounts of energy and time to turn into useful information. Anyone who has used a search engine on the Web, and retrieved thousands of items that were irrelevant to the query, understands the problem. As we learn more about the nature of information, we will be able to use machines and algorithms to sort data and deliver the information that will then become part of our store of knowledge and which will help us to make decisions.

Of the three rapidly developing scientific areas, molecular biology is the most widely recognized by the general public. We are well on our way to having a map of the entire human genome. More significantly we are beginning to understand what functions the genome encodes and how they operate. For better or worse, this is leading to genetically altered plants and animals, and could also be the basis of engineering a much broader array of nonliving materials and products, such as drugs, speciality polymers and new materials.

From a physicist’s viewpoint, however, there will be many fascinating developments in the area where the three scientific disciplines of nanotechnology, molecular biology and information science overlap. These will very likely change the way physics is taught and the way the discipline is organized. Indeed several academic institutions and funding agencies are beginning to recognize that future research demands an interdisciplinary approach and have begun to restructure their science and engineering facilities.

Boom or bust

The major issue to realize about each of these incipient technologies is that progress is, and will continue to be, exponential rather than linear. What does that mean? Take computer chips as an example. In the last 21 years there have been seven new generations of computer chip, each of which contained four times as many transistors as the previous one. During that time, therefore, the improvement in the capability of computers to store and process data has increased by more than a factor of 4⁷, or about 16 000 times. Chips have become much faster because the components in a chip can be arranged closer together as individual components have decreased in size.

These types of advances have led to the creation of entirely new products and services that could not have existed 21 years ago, such as laptop computers, mobile phones, inexpensive digital cameras and the Internet. With the advent of nano-, info- and bio-technologies – each of which has the capacity to grow exponentially for many decades into the future – we can expect the performance of many things that we are familiar with today to improve by factors of 10 000 or more. Even more important, we will see the invention of a wide variety of new goods and services that are impossible today, or are at least extremely expensive or slow. These are dramatic developments, and it will be very hard for humans to adjust to such a rapidly changing environment.

There are also major challenges in dealing with exponential processes. If a person or organization falls behind by just a few weeks, not only do they never catch up with the leader, they also fall further and further behind as time goes on, even if they are accelerating at the same rate as the front-runner. This happened during the late 1980s in the area of dynamic random-access memory (DRAM) chips, when several US companies fell behind their Asian competitors and have since exited the market completely. Exponential progress also makes technology forecasts highly unreliable – if today’s projection is just a few days off, then the error can be amplified to years or decades, depending on how far into the future you are peering.

In the electronics industry the most visible improvement has been in the numbers of transistors that can be integrated onto a single chip – the growth in this case is known as Moore’s Law, after one of the founders of Intel. In other industries, the improvement may be the rate at which information can be transferred or the volume of production of a drug. Exponential growth will occur in each of the nano-, info- and bio-sciences during the early part of the 21st century, each leading to at least one new industrial revolution.

Predicting the future

What can we confidently predict will arise from these new technologies? Nanotechnology will allow people to unobtrusively wear more computer power than is currently available in the largest supercomputers. One might wear it as a watch-like appliance or jewellery, it might fit inside the frame of a pair of glasses, or it might even be woven inside clothing. This computing power will be used to keep people informed, connected and entertained. The amount of information that people will be able to carry with them as back-up memory will be equivalent to the contents of every book ever written.

The World Wide Web will have evolved into an instantly accessible information utility, much like electricity or water. People will be able to go “on-line” with their wearable appliances and actually be able to find useful information that they want, and will be billed for the amount of information they access, just as they are now for linking up to an Internet provider by telephone. That information may be as mundane as the Web address of a good pizza parlour, or as complex as the detailed design of a spacecraft.

It will almost certainly be possible to read the entire genome of an individual human being in the time it now takes to perform a routine medical diagnosis using tools such as magnetic resonance imaging. A doctor will be able to diagnose an illness and prescribe specifically tailored treatments that best suit the individual.

In general, consumer goods will become cheaper, and information will become the most valuable commodity that we will be able to buy. This has the potential for truly liberating and augmenting human creativity, generating entirely new outlets for discovery, improving health and protecting freedom. It also has the potential for great mischief if governments or individuals misuse these tools. One only needs to think of “cyber terrorists” taking computer viruses to an extreme, or the manipulation of the truth as in George Orwell’s 1984. In order for society to survive in this environment, people will have to become more moral.

What types of wildcards could these technologies create? The first interstellar probes may be launched. These would be about the size of a baseball, but they could contain all the different types of instruments that we currently send to our planetary neighbours in probes the size of a bus. They would be so light that we could easily afford the cost of launching them. Their on-board electronics may be so efficient that they could operate for the decades it will take to reach our nearest stellar neighbours using only a single lithium-ion battery like those used in wristwatches today. Once they reach their destinations, the probes could send back images and information with the same quality as our current interplanetary probes. And we could be viewing these images before the 22nd century.

Another possibility is that with various sensors worn on (or perhaps in) the body one could record and store a lifetime’s experiences, and then recall them using wearable appliances. How would this change human behaviour if people knew that their every action was being recorded? And what types of protection would people have for their privacy?

In the next century machines could develop consciousness, which may be a dangerous prospect. Home-based computers may be able to process so much data – perhaps even as much as a thousand human brains – that a hacker could potentially write a self-awareness program. Your best friend, or your worst enemy, could be a household appliance! Would a person be charged with murder if they unplugged a sentient machine?

The future starts here

Any prediction of future technology, including this article, will be wildly over-optimistic in some areas, will fall drastically short in others, and will fail completely to account for the truly radical changes to come. The only thing that we can definitely predict about what technology and physics will look like next century is that it will be profoundly different from the way it is now. As long as we have curiosity and the means to pursue it, we will continue to make new discoveries and learn how to use them to modify our environment.

Rather than reaching the end of science, the beginning of the new millennium will be regarded as a time when we just started to look around us. There is certainly far more to discover than is currently known. The primary barriers to pushing the boundaries of physics are economic, political and social. These issues have always been more difficult to handle than the science.