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“My greatest discovery was that
people would actually pay me to do what I most wanted to do: to satisfy my own
curiosity”. Since his university days, for Sheldon Lee Glashow this has meant
searching for a simple and elegant description of the universe. “For centuries
scientists have been working toward that goal. I have been lucky and persistent enough to
make some major contributions to this magnificent quest”. For these contributions he
received the Nobel Prize in Physics in 1979. |
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Can science save the world? Let me begin with an apology. I shall discuss the economically relevant, environmentally sound, health- and wealth-promoting aspects of science. Yet, I am no expert in these matters and I usually disapprove of those who talk about things of which they know little. I confess to being an unrepentent theoretical particle physicist. Nothing that I have ever done in science is of the least practical importance: my kind of particle physics produces knowledge that is as useless as it is expensive to obtain. But just as a mountain climber climbs a mountain because it is there, I do science simply because I find myself in an endlessly fascinating universe. It is true that science is usually an input into economic activity that generates further prosperity thereby increasing the quality of life. However, science can also be an output that is pleasurable to indulge in, but which absorbs economic resources rather than adding to them, like art, poetry, philosophy and grand opera, which also contribute to the quality of life and the richness of culture. The title I have chosen for my talk is patently and deliberately absurd; it was chosen only to lure you in here. We cannot be so arrogant as to believe that our activities, however irresponsible and unthinking they are, could possibly endanger the Earth or its biosphere. Our planet is under no immediate threat and does not need to be saved. Someday tidal forces will bring the Moon so close to the Earth that it will shatter into millions of fragments and rain destruction everywhere. (Not to worry: right now the Moon is receding from us: but just wait!) Or perhaps the disaster will come from the Sun, which will one day run out of hydrogen fuel. Instead of going out, it will explode so violently as to engulf and destroy its planets. But these dire events will not happen for billions of years. We cannot be so arrogant as to believe that we can avert these heavenly-ordained catastrophes. Nor is it likely that human society, which is now only a few thousand years old, will survive for a million more years, let alone billions. This, of course, is the point of my talk. Although our planet will certainly survive for ages, our civilization is not nearly so secure. Our puny species has spread over the land rather like mold on a slice of bread. Many of our biological cousins have been extinguished by our expansion. Lions, tigers, giant redwoods, as well as countless ``lesser species,'' may soon become extinct. Overpopulation may not be much of a problem today in Europe and North America, but it, and its consequences: hunger, disease and poverty, are ever more serious problems elsewhere in the world. We are given a simple choice: we must control our population growth, or we shall offer our descendents meaner, poorer, sadder and shorter lives on Earth. Had I the talent, the time, and the inclination, I would focus solely on the problem of overpopulation: I believe it to be the most daunting challenge facing humanity. Instead, my lecture will deal with the lesser challenges we face. In a moment, I will list a dozen of them. I trust you wll notice that none of these issues is purely scientific in nature, but that each of them has a substantive scientific component. Science alone cannot answer even one of these questions, but scientists, along with educators, engineers, philosophers, psychologists, sociologists, jounalists, politicians, and especially, an enlightened and scientifically literate citizenry, can answer all of them.
9. Should we detect and defend ourselves against catastrophic meteor impacts?
How is science to address practical and down to earth problems such as these, among many others? Let me begin with a parable first put forth almost a century ago by J.J. Thomson, the discover of the electron. Suppose, he said, that government laboratories had been operating in the stone age. Then we would have had wonderful stone axes, but no one would have discovered metallurgy. ``Research in pure science,'' he wrote, ``is made without any idea of application to industrial matters, but soley with the view of extending our knowledge of the Laws of Nature.'' To demonstrate the utility of pure research, he spoke of X-rays. Let me remind you that X-rays were discovered by Roentgen in 1894. He was not looking for these rays; he came upon them accidentally, or as we say, serendipitously. When a journalist asked ``What did you think?'' Roentgen responded, ``I did not think, I investigated.'' When asked ``What are your rays?'' he said that he did not know. Nonetheless, medical X-rays immediately became a powerful tool for physicians and surgeons. It saved countless lives during the course of the first world war, and ever after. Thomson notes that ``the discovery of X-rays was not the result of research in applied science to find an improved method of locating bullet wounds. This might have led to improved probes, but we cannot imagine it leading to the discovery of X-rays.'' This miracle of practical science, again quoting Thomson, ``is due to an investigation in pure science, made with the object of discovering the nature of electricity.'' The same story occurs again and again throughout the history of science and technology---here are just a few tales I have not the time to tell:
Michael Faraday, one of the greatest scientists of the last century, shared with J.J. Thomson the view of pure science as the parent of technology, and as an enterprise eminently worthwhile in and of itself: ``What study is more fitted to the mind of man than that of the physical sciences? And what is there more capable of giving him an insight into the actions of those laws, a knowledge of which gives interest to the most trifling phenomenon of nature, and makes the observing student find
When Faraday was asked by a woman with a small child, of what value were his seemingly academic electrical researches, he is said to have answered ``Of what value is a newborn child?'' On another occasion, he confessed that he did not know its value, but that someday the Government would put a tax on electricity. In fact, Faraday's investigations of the fundamental properties of electricity led him to the law of electromagnetic induction. It was the key idea underlying the subsequent development of electric power generation, transmission, and its use in the home and in the workplace, on which there is, of course, a tax. Thomson and Faraday were correct in saying that basic science very often leads to results that can be put to good use to improve human welfare. But the other side of the coin is often neglected. Progress in basic science depends critically upon technologica advances, on applied science. Let's return to Roentgen's discovery of X-rays. He produced his rays by applying a high voltage to an evacuated glass tube into which electrodes had been placed; he detected them with photographic film. His experiment made use of technologies developed by three not-very-well educated or particularly famous tinkerers: Rumkorff---who designed a device to produce high voltages; Geissler---who learned how to produce those tubes, and Daguerre---who played a major role in developing photography. Without those unsung heroes of applied science, Roentgen could not have discovered X-rays, Becquerel could not have discovered radioactivity, and Thomson could not have discovered the electron! And so it goes today. Cyclotrons and their kin are used today in many branches of science and technology, such as material design, surface science, particle physics, and cancer therapy. The first cyclotron was invented by a physicist for the pursuit of pure physics, but modern accelerators were developed and designed by specially-trained engineers and applied scientists, both in industry and academia. Astronomy could hardly have gotten off the ground were it not for the development of better telescopes, achromatic lenses, spectroscopes, and once again, photography. Today's orbitting satellites are surely a product of applied science. They are used by spies, by map-makers, by drivers who get lost, and by anyone who makes a very long distance telephone call. However, orbitting observatories also play an essential role in the pusuit of astronomy and cosmology: two of the least practical sciences. (Does it matter that we are learning so much about the birth and fate of the universe? Later on, I will argue that it does!) Indeed, basic science could not progress at all without the fruits of industry: vacuum pumps, spectroscopic analyzers, ultracentrifuges, synchrotron light sources, supercomputers, etc. Basic science relies just as much on applied science as applied science relies on basic science. We cannot have one without the other, and we should not even try. Twentieth century life in the developed world is incomparably different from what it was like in the 19th century. What led to these changes? Surely, all the world's kings, generals, presidents, and politicians played a role, but a minor one. So did all the world's architects, writers, artists and musicians. But most of the changes in our way of life resulted from advances in science, technology, and medicine. The history of civilization is closely linked to the history of science, much more closely than many scientifically unread historians may realize. In a like manner, the 21st century will be very different from our century, but I dare not even try to predict the changes. One thing, however, is clear: the relation between pure or fundamental science on the one hand, and applied or practical science on the other is changing rapidly: in the biological sciences, they are coming closer together, but in the physical sciences, they are drawing further apart. Modern medicine, despite its many triumphs, is not yet an exact science. Many new drugs, new devices and new procedures are devised every year. They are carefully tested for safety and efficacy, first on animals, then on people. Most of the time, they don't work very well, but occasionally they do. When that happens, the new therapies are added to the physician's tool-box. It's more an art than a science. But today, we are learning how the body works at a microscopic level. Soon, the human genome will be mapped and many medical miracles will become possible, if scientist learn how to deal with the immense amount of information contained in our genes. Many dire diseases will become preventable or reversible. Cancer patients will be cured much more often, because the particular cellular mutation causing their disease will be identified, and the appropriate therapy administered. Today, physicists, chemists, computer scientists, ethical philosophers, and biologists are working together to explore the most fundamental processes of life. Thanks to their very basic research, medicine is fast becoming a precise and quantitative science. What about the physical sciences? In the past, fundamental discoveries (such as X-rays, radio waves, relativity, and quantum mechanics) led directly to many useful devices (such as CAT scanners, color TV, nuclear energy, lasers, transistors, and microchips). Even positrons (a form of antimatter discovered in 1932) have found medical applications. But what of recent discoveries in fundamental physical science? We particle physicists are fascinated by the so-called strange particles and by particles with strange names, like neutrinos, pions, and muons. We've studied them for fifty years, but they have not found any practical use, and may never do. Similarly for quarks, gluons, and for various bosons bearing physicist's names, and even more so for the fanciful superstrings that the best and brightest theoretical physicists believe to be the basis of all matter. For that matter, what about all those strange monsters lying far, far away in space: pulsars, quasars, black holes, supernovae, and the billions of galaxies in the universe, each consisting of billions of stars? How important are they to everyday life? In the words of a clerical critic of Galileo's telescopic discoveries: These things ``are invisible to the naked eye, and therefore can have no influence on the earth, and therefore do not exist.'' Fundamental physical science has grown apart from the work-a-day world. The most profound unsolved problems lie at the extremes of the ladder of size: in the microworld of sub-atomic particles and in the cosmos. Richard Feynman described the goal of fundamental physics this way:
Of course, knowing the rules of chess does not make one a grand master. Feynman continues: ``What we really can explain in terms of those rules is very limited, because almost all situations are so enormously complicated that we cannot follow the plays of the game using the rules, much less tell what is going to happen next.'' We've been remarkably adept at learning the rules. In fact, the fundamental principles governing the behavior of ordinary matter under ordinary conditions have pretty much been set in stone for over half a century. It is very unlikely that we've got the rules wrong, and it's equally unlikely that we're missing some rules. Matter (including your bodies) is just a great big bunch of electrons and various atomic nuclei interacting electromagnetically and obeying Schroedinger's equation. There are no unknown forces, mysterious emanations, or vital fluids. Cold fusion, homeopathic dilution, horoscopes, and extrasensory perception make no more sense than animal magnetism, crystal balls, reading tea leaves, or other forms of divination. Many of the fundamental questions of physical science have been answered, at least in principle. Those that still vex us have to do with things that are far too small or too far away to affect the everyday world. Finding out the rules was an essential first step, but there's a lot more to basic science than that. Why? Because, even knowing all the relevant rules, answering such a simple question as why water is transparent and expands when it freezes is devilishly difficult---let alone answering such tough questions as what the weather will be tomorrow or how a child learns to walk and talk. There's more basic science to do today than ever before, and many unexpected wonders of nature are hidden in the complexity of things and not yet revealed to us. The so-called end of science is a mirage: science is truly the endless frontier. Perhaps this an appropriate point to mention the changing relationship between academia and industry. As the distinction between basic and applied science blurs, it's downright silly to keep these enterprises entirely separate from one another. University researchers should be encoraged to exploit their discoveries, just as industrial labs should pursue undirected basic research. These traditions exist in the States, for example, at the Bell Laboratories of the Lucent Corporation, and at the Photonics center of Boston University. We should anticipate and foster many even closer links between academia and industry in the next millenium. Next, let's talk about `spin-off,' a term that describes how research in one direction can lead to developments in quite different directions. We've mentioned a few examples from the past; here are a few modern instances: The Vela satellites, designed to detect Soviet violations of the test ban treaty in the 1960's, instead discovered curious signals of distant cosmic catastrophes, which are only now beginning to be understood. Reagan's Strategic Defense Initiative led to developments in adaptive optics that allow telescopes to filter out the twinkling of the atmosphere; some of the materials used in designer ladies bags (such as are found in Milan's boutiques) were developed in the space program, along with an unpalatable but oddly popular beverage (Tang) originally foisted on astronauts. However, I have in mind a far more significant sort of spinoff effect: one involving people rather than things. Ours is a technological society. Most of us can simply use such things as cars, computers, and celular phones. But some of us must understand how they work, and others must address the problems that beset us, many of which were caused by the new technologies. The functioning of modern society depends on our well-trained engineers and applied scientists. Who are they and who will teach them? Things have gotten much too complicated for on-the-job training. Tomorrow's teachers and scientists are today's inquisative children. Children often ask the same sorts of questions that basic scientists do: How did the world begin? What makes stars shine? How do rabbits make more rabbits? If only they could be encouraged to continue to ask these questions when they grow up... I'm suggesting what's called a bait and switch operation: get the kid interested in quarks and quasars so she learns some physics, and maybe she'll grow up to be a scientist and invent a better battery or a cure for baldness. At Harvard, we encounter many talented youngsters who dream of a career in pure science: hordes of potential Einsteins or or little Miss Curies. Some of them will attain their dream, but most will be diverted. Many of our highly-trained physics students choose to become biologists, computer scientists, physicians or patent attorneys; others become businessmen, sometimes starting their own companies and occasionally becoming very wealthy. (Ed Land, the founder of Polaroid, was a physics major at Harvard before he dropped out of school and went into business.) Here's another example in the field of combinatorial mathematics, a discipline described by my late MIT colleague Gian-Carlo Rota as ``counting the ways of putting differently colored marbles in differently colored boxes.'' (Gian-Carlo, who was born not far from Milan, passed away just last month.) What could be less practical? Surprisingly, it's become a very useful science. It's used by shipping companies to minimize their costs, and by governments to reduce their telephone charges. Professor Rota observed that many of his best students go to Wall Street. ``It turns out,'' he wrote, ``that the best financial analysts are either mathematicians or theoretical physicists.'' Indeed, many of our physics students and young faculty have switched to more remunerative careers on Wall Street. Let me conclude this discussion with three exceptional instances of pure scientists---particle physicists all---who made truly important contributions to society in quite different disciplines. Alan Cormack was an experimental high-energy physicist at Tufts university. He taught and studied the exotic discipline of elementary particle physics. In his spare time he developed the technology underlying the CAT scanner, whose importance in modern medicine is well known. He and Geoffrey Houndstooth (another particle physicist) shared the Nobel Prize in Medicine for this work. Walter Gilbert was trained as a mathematical physicist: he was, at one time, as pure a scientist as may be imagined. He was an accomplished one as well, with tenure at Harvard. Following a distinguished tradition, he switched fields in mid career, and went on to make several truly seminal discoveries in molecular biology and the causation of cancer (and to found Biogen, a pharmaceutical company whose stock has quadrupled in the last few months). For his discovery of the repressor, Gilbert was awarded the Nobel Prize in Chemistry. Andrei Sakharov was a cosmologist and a theoretical particle physicist. Among many other accomplishments, he found an explanation for why there is matter in the universe, but very little antimatter. However, Sakharov was a champion of human rights in the Soviet Union and was largely responsible for convincing his government to sign the nuclear test ban agreement. Sakharov was awarded the Nobel Prize in Peace. We can conclude that training in fundamental particle physics is not quite so useless as it may appear: Cormack, Gilbert, and Sakharov are just a few of of those who began their careers in pure science, but who spun themselves off so as to contribute magnificently to human welfare. Here's one more virtue of basic scientific research. Science is one of a very few examples of successful international cooperation. This is not something new: science has rarely recognized national or cultural boundaries. For example, five men taught us our place in the universe: Copernicus (a Pole), Tycho Brahe (a Dane), Kepler (a German), Galileo (an Italian), and Newton (an Englishman). Science continues as a multinational and multicultural enterprise, but today's scientists are no longer exclusively dead, white, European, Christian men. Listen:
The problems facing society are severe. Like the problems facing particle physicists, they are too complex for any one nation to address. If the physicists of the world can can cooperate so effectively, should this not serve as a paradigm for others? I shall conclude my talk with one last argument for the importance of pure science, even when it is so pure that it offers no hope of immediate practical application. No one said it better than Primo Levi: an applied chemist, a holocaust survivor, and a superbly moving author. Please forgive me for offering an English translation of his Italian prose:
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