What I want to talk about is the problem of manipulating and controlling things on a small scale…. It is a staggeringly small world that is below. In the year 2000, when they look back at this age, they will wonder why it was not until the year 1960 that anybody began seriously to move in this direction. Richard Feynman Richard Feynman and nanotechnology In 1959, in an after dinner speech at a meeting of the American Physical Society in Pasadena, Richard Feynman set out a remarkable vision of the future in a talk entitled ‘There's plenty of room at the bottom.’ The talk was subtitled ‘an invitation to enter a new field of physics’ and marked the beginning of what is now known as ‘nanotechnology’. Nanotechnology is concerned with the manipulation of matter at the scale of a nanometre -a thousand millionth of a metre. Atoms are typically a few tenths of a nanometre in size. Feynman emphasized that such an endeavour does not need new physics: I am not inventing anti-gravity, which is possible someday only if the laws are not what we think. I am telling you what could be done if the laws are what we think; we are not doing it simply because we haven't yet gotten around to it. In his talk Feynman offered two prizes of $1000 each – one ‘to the first guy who makes an operating electric motor which is only 1/64 inch cube’, and a second ‘to the first guy who can take the information on the page of a book and put it on an area 1/25000 smaller’ He had to pay out on both prizes – the first less than a year later, to Bill McLellan, a Caltech alumnus.
What I want to talk about is the problem of manipulating and controlling things on a small scale…. It is a staggeringly small world that is below. In the year 2000, when they look back at this age, they will wonder why it was not until the year 1960 that anybody began seriously to move in this direction. Richard Feynman Richard Feynman and nanotechnology In 1959, in an after dinner speech at a meeting of the American Physical Society in Pasadena, Richard Feynman set out a remarkable vision of the future in a talk entitled ‘There's plenty of room at the bottom.’ The talk was subtitled ‘an invitation to enter a new field of physics’ and marked the beginning of what is now known as ‘nanotechnology’. Nanotechnology is concerned with the manipulation of matter at the scale of a nanometre -a thousand millionth of a metre. Atoms are typically a few tenths of a nanometre in size. Feynman emphasized that such an endeavour does not need new physics: I am not inventing anti-gravity, which is possible someday only if the laws are not what we think. I am telling you what could be done if the laws are what we think; we are not doing it simply because we haven't yet gotten around to it. In his talk Feynman offered two prizes of $1000 each – one ‘to the first guy who makes an operating electric motor which is only 1/64 inch cube’, and a second ‘to the first guy who can take the information on the page of a book and put it on an area 1/25000 smaller’ He had to pay out on both prizes – the first less than a year later, to Bill McLellan, a Caltech alumnus.
One group of physicists simply assumed that atoms exist, picturing them as tiny particles bouncing around in accordance with Newton's laws. The arrival of quantum mechanics gave new insights into the behaviour of matter, and it is now apparent that many important and useful properties of materials are due to quantum mechanical effects. In this course, our discussion of the physics of matter is split into two parts. The central importance of atoms has been emphasized by Richard Feynman, Nobel laureate and one of the greatest physicists of recent times. Ironically, just as the existence of atoms was being demonstrated beyond any reasonable doubt at the beginning of the twentieth century, the foundations of Newtonian mechanics were being shaken by the first glimmerings of quantum theory.
The turn of the XXth century witnessed a revolution in physics comparable to Isaac Newton’s discovery of the universal laws of mechanics and of gravitation three centuries earlier. The world required to be described in novel terms, as the immutable, deterministic view of our familiar universe had given way to a new world picture, one which featured chance, flux, and an incessant upsurge of waves of matter. Such a worldview was so radically new and counterintuitive that it gave rise to strong debates, to the effect that Albert Einstein himself tried to oppose it on the grounds that “God does not play dice”. In spite of the intense debates that accompanied its emergence, quantum mechanics quickly proved an incredibly efficacious new tool to understand and to predict a wide array of new phenomena. It was so successful that in no time it broke free from the environment of research labs to become part of daily life, making it possible, for example, to understand why some materials were conductors, while others were insulators. Along with it, came, too, the discovery of transistors, on which much of modern electronics rests. It also led to understand how novel materials known as superconductors allow the transport of electricity with no loss, thus paving the way for new developments in the fields of medical imagery or energy distribution. Other aspects of the quantum theory led to the development of atomic clocks of astounding accuracy, which would be wrong by no more than fifteen seconds, had they been set at the beginning of the universe. A hundred years later, at the turn of the XXIst century, Quantum mechanics has lost none of its astounding power. Contemporary research has undertaken the task of exploring its less immediately perceptible aspects. Groundbreaking developments have ensued, such as the teleportation of grains of light or the possibility, once predicted by the great physicist Richard Feynman, to build, one day, novel computers which, unlike the ones we are familiar with today, will be able to process innumerable numbers of operations in parallel. The Wright Colloquium will be for us the occasion to explore, in the company of five internationallyknown specialists in the field, some of the fascinating aspects of quantum mechanics. We will appraise how efficiently quantum physics can describe our world, and confront its limitation when it is faced with the infinitely small (in relation to recent experiments carried out at the CERN) as with the incommensurably large scale of sidereal spaces. We will appreciate the extent to which quantum physics already has impacted our everyday lives, and evoke the way in which novel fields such as quantum computers and quantum information will entail profound changes in the future. The quantum adventure has only just begun! Monday 15 November 2010 - 18h30 Jochen Mannhart Center for Electronic Correlations and Magnetism, University of Augsburg, Germany Quantum Physics on the Scale of Daily Life Tuesday 16 November 2010 - 18h30 Wolfgang Ketterle Nobel Laureate 2001 (Physics), Department of Physics, Massachusetts Institute of Technology, Cambridge, U.S.A. When freezing cold is not cold enough New forms of matter close to absolute zero temperature Wednesday 17 November 2010 - 18h30 David Gross Nobel Laureate 2004 (Physics), Kavli Institute for Theoretical Physics, University of California, Santa-Barbara, U.S.A. Quantum Mechanics of the Very, Very Small and the Very, Very Large Thursday 18 November 2010 - 18h30 Alain Aspect CNRS senior scientist and Professor Institut d'Optique and Ecole Polytechnique Palaiseau, France. From Einstein’s intuition to quantum bits: a new quantum age? Vendredi 19 novembre 2010 - 18h30 Rainer Blatt Institute of Quantum Optics and Quantum Information, Austrian Academy of Sciences and University of Innsbruck, Austria The Quantum Way of Doing Computations
It is difficult to venture into the world of the ultimately small, or even to talk about it, without a very good understanding of the laws of Nature that govern that world. The forces one finds there determine the way in which the tiny particles we wish to study move about, and also all their other properties. Whether, and how, we can actually observe them will also depend on these forces. And this is not easy, because the laws of Nature are complicated. More and more experts in this field seek refuge in a kind of mathematical gibberish no ‘normal’ person can follow, unless he or she belongs to the in-crowd. To really appreciate the rock-solid logic of the laws of physics, one actually cannot avoid math. Nonetheless, we physicists feel the need to share the joy of all our beautiful discoveries with whoever wants to listen. We are advised then to avoid all math. This then is what I shall reluctantly do. It is my intention to provide a narrative of twenty-five years of research on the very tiniest particles of matter. During those twenty-five years, I began to view Nature as an intelligence test to which humanity as a whole has been subjected, as a giant jigsaw puzzle given to us to play with. Time and again, we stumble upon new pieces, large or small, that fit beautifully with those we already have. I want to share with you the sense of triumph we feel at such moments.
Unlike special relativity, quantum mechanics was not the inspired product of one mind. It developed, in fits and starts, over a period of 25 years (1900–1925), and many cooks stirred the broth. Even now, a century later, quantum mechanics raises profound conceptual questions. Every competent physicist can “do” quantum mechanics, and the predictions it makes are in spectacularly good agreement with experimental results; there can be little doubt that quantum mechanics is “right.” On the other hand, as Richard Feynman once remarked, “nobody understands quantum mechanics.” I'll tell the story in two parts. First the history (how the essential pieces of the puzzle were assembled), and then the implications (what the finished picture has to say about our world). Photons Like relativity, quantum mechanics began with the study of light. In both cases, this historical association is misleading. Relativity, really, has nothing to do with light – to be sure, it involves that magic speed limit, c , and of course the most familiar thing that travels at speed c is light. So light is a convenient vehicle for introducing the subject. But it is perfectly possible to imagine a universe in which there is no such thing as light, and yet relativity might still be valid. Quantum mechanics, too, starts with light – in this case the “quantum” of light (the photon). But, as it turns out, this is just one rather specialized example of much more general principles – in fact, a rather bad example, because photons are by their nature relativistic (they travel at the speed of light), and it would be more natural to begin with the quantum mechanics of slow-moving objects, in analogy with Newtonian mechanics.
Although this book focuses on backgrounds of quantum optics, it is nevertheless appropriate to conclude by emphasizing the importance of quantum optics in the development of new areas in science and technology. The predictions of quantum optics have turned research and technology into new directions and have led to numerous technological innovations and the development of a new technology on the scale of single atoms and electrons, called quantum technology, or nanotechnology. The ability to manufacture tiny structures, such as quantum dots, and to control their dimensions allows us to engineer the unique properties of these structures and predict new devices such as quantum computers. A quantum computer can perform mathematical calculations much faster and store much more information than a classical computer by using the laws of quantum physics. The technology for creating a quantum computer is still in its infancy because it is extremely difficult to control quantum systems, but is developing very rapidly with little sign of the progress slowing.
Feynman is also widely credited with inventing the eld of nanotechnology with a famous lecture, “ere’s Plenty of Room at the Bottom,” delivered at the 1959 meeting of the American Physical Society held at the California Institute of Technology in Pasadena. e “nano” in nanotechnology comes from the Greek word for “dwarf” and we use it in the scientic unit of length-the nanometer-which is 1 billionth of a meter or 40 billionths of an inch. An atom of silicon, the stu Intel makes computer chips from, is approximately a quarter of a nanometer in diameter. In his lecture, Feynman speculated on new technologies that would evolve from man’s ability to manipulate matter on such nanometer-sized atomic scales.4 Feynman declared, “And it turns out that all of the information that man has carefully accumulated in all the books in the world can be written in this form in a cube of material one two-hundredth of an inch wide-which is the barest piece of dust that can be made out by the human eye. So there is plenty of room at the bottom!”