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[an error occurred while processing this directive] Order Inspection copy		The Social Benefit of High-Energy Physics by Frank Wilczek (MIT)   Compared to most scientific endeavors, though not to space exploration or to some defense-related technology research, high-energy physics is an expensive enterprise. Modern accelerator facilities capable of expanding the high-energy frontier, such as Fermilab or the CERN Large Hadron Collider (LHC) project, are big science, involving the concerted efforts of thousands of people and costing several billions of dollars. High-energy physics has been supported almost entirely by government agencies, and thus ultimately by taxpayers. It is entirely appropriate that scientists who promote these expenditures should be expected to justify this investment by society as a whole, by explaining its benefits to society as a whole. To address this challenge in an honest and meaningful way, we must begin by reviewing, in broad terms, the nature and goals of modern high-energy physics. The primary aim of research in high-energy physics is easily stated. It is, simply, to produce a better understanding of fundamental physical law, by following a reductionist strategy. That is, we attempt to understand the behavior of matter in general by working up from profound under-standing of the properties and interactions of its elementary constituents. This strategy has proven remarkably fruitful and successful, especially over the course of the twentieth century. We have discovered that strange but precise and elegant mathematical laws, summarized in the so-called Standard Model, govern the laws of physics on subatomic scales. There is every reason to think that these laws, as presently formulated, are adequate to serve as the foundation for materials science, chemistry (including biochemistry), and most of astrophysics One must be careful in interpreting that sort of statement, which superficially might appear quite arrogant. Chemists in pursuit of their profession are rarely, if ever, concerned with the equations of QCD. They take the existence and basic properties of atomic nuclei as given. For most chemical purposes it is adequate to approximate nuclei as point-like concentrations of charge and mass. In a few chemical applications nuclear spin also plays a role, but rarely any other aspect of nuclear structure. So in saying that QCD provides part of the "foundation" for chemistry, one means no more (and no less) than that it provides equations which in principle should allow one to derive the existence of nuclei, and to calculate a few of their properties, from a few proven properties of their constituent quarks and gluons. It does not thereby directly solve, or even address, any properly chemical problems. In the same spirit, we might say that acoustics provides the foundation for music, or lexicography the foundation for literature. As the inner frontier of the reductionist program has moved from explaining matter in terms of atoms, to explaining atoms in terms of electrons and nuclei, to explaining nuclei in terms of protons and neutrons, and these in turn using quarks and gluons, the models it creates have become ever more accurate and more broadly applicable. But with this progression, the domain of phenomena for which the new models provide qualitatively new insights, as opposed to better foundations, has grown increasingly remote from everyday life. Subatomic physics allowed us to understand and refine the basic principles of chemistry and to design materials with desired electric and magnetic properties; nuclear physics allowed us to understand the energy source of stars and the relative abundance of the elements; quark-gluon physics allowed us to understand the behavior of matter in the very early Universe. Future developments may help us to penetrate more deeply into the early moments of the Big Bang, or to recognize and understand yet undiscovered extreme astronomical environments, but apart from this it is hard to anticipate their direct application to the natural world. It would be quite disingenuous to hold out the promise of economically significant new technologies based on future discoveries in high-energy physics. If we take a broader perspective, however, the picture looks quite different. Over recent history, again and again fundamental, curiosity-driven research has led to unexpected developments and spin-offs whose economic value far exceeds the cost of the investments that spawned them. Sometimes the payoff was delayed by many decades, and came from directions that no one remotely anticipated. The whole world of radio and wireless communication grew from Faraday's vision of empty space as a dynamical medium and the experiments it inspired. Lasers and digital cameras grew from the struggles of Planck and Einstein to understand the strange wave/particle dualism of light/photons. Modern microelectronics, with all its ramifications, grew out of Thomson's discovery of electrons and the revolutionary insights of Bohr, Heisenberg and Schrödinger in quantum theory. Nor do we lack examples closer to the present, recognizably belonging to the modern era of high-energy physics. The central tools of the field, accelerators, have become a ubiquitous medical device. Their simplest and most familiar incarnation, perhaps, are X-ray machines, but other particle beams are used in cancer therapy and for diagnosis. Who would have thought that reconciling quantum theory theoretically with special relativity would lead to important clinical technologies for medicine? Yet Dirac's theory predicted antimatter, and positron emission tomography (PET scan) has become a powerful tool for looking inside the brain. Another major application of accelerators is mass spectroscopy. This method of dating and analyzing the composition of materials has supported significant contributions to geology, archaeology, and art history. At this moment, synchotron light sources are providing new, cutting-edge tools to structural biology and chemical dynamics. In high-energy physics the production of synchotron radiation, an inevitable accompaniment of charged particle acceleration, was initially regarded as a nuisance, since it drains energy from the particles we try to accelerate. But it turns out that this "waste-product" allows scientists to look at molecules with unprecedented resolution in space and time. So now special accelerators are designed specifically to be sources of synchotron radiation. They are used for medical diagnosis, drug design, and many other practical purposes. Besides its direct impact, the development of high-energy accelerators has also spurred progress in a number of supporting technologies. To construct the accelerators, physicists had to design large powerful magnets, to guide the particles' orbits. Magnets of this sort have become the workhorse of magnetic resonance imaging (MRI), another major medical technology. A completely unanticipated, quite recent spin-off of high-energy physics is in the process of becoming the most important of all. Modern high-energy physics experiments typically involve many tens or even hundreds of collaborators, who must share their data and their analyses. It was to facilitate that process of collaboration that Tim Berners-Lee, a software engineer working at CERN, developed the concept of the World Wide Web, and the first browser-editor, thus starting the Internet revolution. Many other innovations in high-speed electronics, less well-known but central to commercial computing and communication technology, were developed in response to the challenges of guiding vast numbers of particles moving at velocities very close to the speed of light, and interpreting the complicated results their collisions produce. More difficult to identify specifically, but also important, are spin-offs from conceptual developments in high-energy physics. Quantum field theory was developed as the rigorous language of elementary processes, but also turns out to be the appropriate tool to understand supercon-ductivity. The renormalization group, first developed as a technical tool within quantum field theory, turns out to be the key to understanding phase transitions, and is playing a dominant role in emerging theories of pattern-formation, chaos, and turbulence. Why do such valuable surprises occur so regularly? I think there is a simple, yet profound explanation. In essence, it was put forward by William James, who spoke of "the moral equivalent of war." It is the fact that human beings can be inspired by difficult problems and challenges to work very hard and selflessly, and to find more in themselves than they knew existed. Especially in youth, they even seem driven to seek — or manufacture! — such problems. Perhaps evolution selected the ability to rise to challenges partly in response to the pressures of human conflict. In any case, we should exploit opportunities to direct that precious ability into constructive channels. High-energy physics does not lack for tough challenges. Ultimate questions about the unification of fundamental forces and the origin of the Universe begin to seem accessible. On the experimental side the challenges are more tangible, and no less awesome. The next generation of accelerators will be engineering projects of grandeur, both in their size and in their precision. They will be our civilization's answer to the Pyramids of Egypt, but nobler, built to improve our understanding rather than to appease superstition and tyrannical theocracy. We must learn how to handle the tremendous flow of data these accelerators will generate. The ATLAS experiment already planned for CERN's Large Hadron Collider is expected to collect 1015 bytes/year -- equivalent to a million human genomes. Amidst this torrent we must identify the fraction, probably a mere trickle, which does not fit the Standard Model. We will need to develop new ultrafast methods of communication and computation. It would be surprising if the effort of rising to these challenges failed to produce some spectacular by- products. In short, the economic fruits of fundamental investigation, though unpredictable in detail, have arrived with wonderful reliability, and have been reliably wonderful. Investment in this area is ultimately an investment in people, specifically in the power of great problems to inspire great efforts. The human effects of big scientific projects ramify far beyond their immediate research community. Construction of a modern high-energy accelerator, its detectors, and its information infrastructure brings engineers into intimate contact with exotic frontiers of technology and with problems of a quite different nature from those they would ordinarily encounter. Also, most of the young people going into these projects will not find permanent academic employment. They enter this life with open eyes, foregoing security for the opportunity to participate in something great. When these engineers and researchers return to the outside world, they bring with them unique skills and experience. Finally, the visible commitment of society to high-profile scientific endeavors sends an important message to young people considering what career to enter, encouraging them in scientific and technological directions. That's important, because our society needs capable scientists and engineers, and they are always in great demand. So much for spin-offs and indirect benefits. Now let us discuss the intrinsic worth of the prospective knowledge. There are several specific questions that seem ripe for progress: Universal ether and the origin of mass -- Our theory of the weak and electromagnetic interactions postulates that what we ordinarily regard as empty space is in fact filled with a pervasive medium, or ether. It is only by interacting with this ether that many particles, notably including the W and Z bosons, which mediate the weak interaction, acquire their mass. Although the theory is extremely successful, this central aspect of it has not been tested directly. We hope to excite ether, which will either produce so-called Higgs particles, or reveal some more complex structure. Unification of the Theory of Matter -- The Standard Model, containing the theory of the weak, electromagnetic and strong interactions, provides a remarkably complete theory of the behavior of matter. The different pieces of the Standard Model have related mathematical structures, embodying various symmetries. It is natural to speculate that there is a single master symmetry that includes them all, and goes beyond. We have some promising ideas about how this might occur, and some tantalizing hints that the basic idea is on the right track, but the decisive work has not yet been done. Supersymmetry -- The logic of unification leads to another remarkable idea, supersymmetry. Supersymmetry postulates the addition of extra quantum-mechanical dimensions. Movement of particles into these dimensions will make them appear to be other kinds of particles that have quite different, but predictable properties. So far none of the new particles has been found, but according to theory they will begin showing up in higher-energy collisions, opening up a strange new world. The Arrow of Time -- We have observed a few exceptional microscopic processes that exhibit a preferred direction in time (that look different when run backward). This phenomenon is central to our understanding of how the cosmic asymmetry between matter and antimatter arose. To understand it properly, we need to see more examples of how it works, especially at high energy. Unification with Gravity -- The theory of gravity (Einstein's general relativity) is not deeply integrated into the theory of matter (the so-called Standard Model). But there are bold ideas for how a completely unified theory, that describes both matter and gravity, might be con-structed. Some of those ideas lead to predictions of new particles, and of specific patterns among their masses. Discoveries here could open windows into the nature of quantum gravity, or extra curled-up spatial dimensions. Continued pursuit of the ultimate foundations of physical behavior expresses our society's commitment to the deepest ideals of scientific culture: to pursue the truth wherever it leads; to ground our working picture of Nature in empirical realities; and to challenge it.   Excerpted from Fantastic Realities Copyright © 2006 by Frank Wilczek. All rights reserved. No part of this excerpt may be reproduced or reprinted without permission in writing from the publisher.
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