Based on courses given at the CRM Banff summer school in 1999, this volume provides a snapshot of topics engaging theoretical physicists at the end of the twentieth century and the beginning of the twenty-first. Young physicists will find in these chapters pedagogical introductions to subjects currently active in theoretical physics, and more seasoned physicists will find a chance to share the excitement of fields outside their immediate research interests.

At the end of the nineteenth century, some physicists believed that the basic principles underlying their subject were already known, and that physics in the future would only consist of filling in the details. They could hardly have been more wrong. The past century has seen the rise of quantum mechanics, relativity, cosmology, particle physics, and solid-state physics, among other fields. These subjects have fundamentally changed our understanding of space, time, and matter. They have also transformed daily life, inspiring a technological revolution that has included the development of radio, television, lasers, nuclear power, and computers. In Quantum Generations, Helge Kragh, one of the world's leading historians of physics, presents a sweeping account of these extraordinary achievements of the past one hundred years. The first comprehensive one-volume history of twentieth-century physics, the book takes us from the discovery of X rays in the mid-1890s to superstring theory in the 1990s. Unlike most previous histories of physics, written either from a scientific perspective or from a social and institutional perspective, Quantum Generations combines both approaches. Kragh writes about pure science with the expertise of a trained physicist, while keeping the content accessible to nonspecialists and paying careful attention to practical uses of science, ranging from compact disks to bombs. As a historian, Kragh skillfully outlines the social and economic contexts that have shaped the field in the twentieth century. He writes, for example, about the impact of the two world wars, the fate of physics under Hitler, Mussolini, and Stalin, the role of military research, the emerging leadership of the United States, and the backlash against science that began in the 1960s. He also shows how the revolutionary discoveries of scientists ranging from Einstein, Planck, and Bohr to Stephen Hawking have been built on the great traditions of earlier centuries. Combining a mastery of detail with a sure sense of the broad contours of historical change, Kragh has written a fitting tribute to the scientists who have played such a decisive role in the making of the modern world.

In Shifting Standards, Allan Franklin provides an overview of notable experiments in particle physics. Using papers published in Physical Review, the journal of the American Physical Society, as his basis, Franklin details the experiments themselves, their data collection, the events witnessed, and the interpretation of results. From these papers, he distills the dramatic changes to particle physics experimentation from 1894 through 2009. Franklin develops a framework for his analysis, viewing each example according to exclusion and selection of data; possible experimenter bias; details of the experimental apparatus; size of the data set, apparatus, and number of authors; rates of data taking along with analysis and reduction; distinction between ideal and actual experiments; historical accounts of previous experiments; and personal comments and style. From Millikan's tabletop oil-drop experiment to the Compact Muon Solenoid apparatus measuring approximately 4,000 cubic meters (not including accelerators) and employing over 2,000 authors, Franklin's study follows the decade-by-decade evolution of scale and standards in particle physics experimentation. As he shows, where once there were only one or two collaborators, now it literally takes a village. Similar changes are seen in data collection: in 1909 Millikan's data set took 175 oil drops, of which he used 23 to determine the value of e, the charge of the electron; in contrast, the 1988-1992 E791 experiment using the Collider Detector at Fermilab, investigating the hadroproduction of charm quarks, recorded 20 billion events. As we also see, data collection took a quantum leap in the 1950s with the use of computers. Events are now recorded at rates as of a few hundred per second, and analysis rates have progressed similarly. Employing his epistemology of experimentation, Franklin deconstructs each example to view the arguments offered and the correctness of the results. Overall, he finds that despite the metamorphosis of the process, the role of experimentation has remained remarkably consistent through the years: to test theories and provide factual basis for scientific knowledge, to encourage new theories, and to reveal new phenomenon.

A daring new vision of the quantum universe, and the scandals controversies, and questions that may illuminate our future--from Canada's leading mind on contemporary physics. Quantum physics is the golden child of modern science. It is the basis of our understanding of atoms, radiation, and so much else, from elementary particles and basic forces to the behaviour of materials. But for a century it has also been the problem child of science, plagued by intense disagreements between its intellectual giants, from Albert Einstein to Stephen Hawking, over the strange paradoxes and implications that seem like the stuff of fantasy. Whether it's Schrödinger's cat--a creature that is simultaneously dead and alive--or a belief that the world does not exist independently of our observations of it, quantum theory is what challenges our fundamental assumptions about our reality. In Einstein's Unfinished Revolution, globally renowned theoretical physicist Lee Smolin provocatively argues that the problems which have bedeviled quantum physics since its inception are unsolved for the simple reason that the theory is incomplete. There is more, waiting to be discovered. Our task--if we are to have simple answers to our simple questions about the universe we live in--must be to go beyond it to a description of the world on an atomic scale that makes sense. In this vibrant and accessible book, Smolin takes us on a journey through the basics of quantum physics, introducing the stories of the experiments and figures that have transformed the field, before wrestling with the puzzles and conundrums that they present. Along the way, he illuminates the existing theories about the quantum world that might solve these problems, guiding us toward his own vision that embraces common sense realism. If we are to have any hope of completing the revolution that Einstein began nearly a century ago, we must go beyond quantum mechanics as we know it to find a theory that will give us a complete description of nature. In Einstein's Unfinished Revolution, Lee Smolin brings us a step closer to resolving one of the greatest scientific controversies of our age.

The revolution in twentieth century physics has changed the way we think about space, time and matter and our own place in the universe. It has offered answers to many of the big questions of existence, such as the ultimate nature of things and the how the universe came into being. It has undermined our belief in a Newtonian mechanistic universe and a deterministic future, posing questions about parallel universes, time-travel and the origin and end of everything. At the same time we have witnessed amazing attempts at unification so that physicists are able to contemplate the discovery of a single 'theory of everything' from which we could derive the masses and types of all particles and their interactions. This book tells the story of these discoveries and the people who made them, largely through the work of Nobel Prize winning physicists.

Many of the scientific breakthroughs of the twentieth century were first reported in the journal Nature. A Century of Nature brings together in one volume Nature's greatest hits—reproductions of seminal contributions that changed science and the world, accompanied by essays written by leading scientists (including four Nobel laureates) that provide historical context for each article, explain its insights in graceful, accessible prose, and celebrate the serendipity of discovery and the rewards of searching for needles in haystacks.

INSTANT NEW YORK TIMES BESTSELLER As you read these words, copies of you are being created. Sean Carroll, theoretical physicist and one of this world’s most celebrated writers on science, rewrites the history of twentieth-century physics. Already hailed as a masterpiece, Something Deeply Hidden shows for the first time that facing up to the essential puzzle of quantum mechanics utterly transforms how we think about space and time. His reconciling of quantum mechanics with Einstein’s theory of relativity changes, well, everything. Most physicists haven’t even recognized the uncomfortable truth: Physics has been in crisis since 1927. Quantum mechanics has always had obvious gaps—which have come to be simply ignored. Science popularizers keep telling us how weird it is, how impossible it is to understand. Academics discourage students from working on the "dead end" of quantum foundations. Putting his professional reputation on the line with this audacious yet entirely reasonable book, Carroll says that the crisis can now come to an end. We just have to accept that there is more than one of us in the universe. There are many, many Sean Carrolls. Many of every one of us. Copies of you are generated thousands of times per second. The Many-Worlds theory of quantum behavior says that every time there is a quantum event, a world splits off with everything in it the same, except in that other world the quantum event didn't happen. Step-by-step in Carroll's uniquely lucid way, he tackles the major objections to this otherworldly revelation until his case is inescapably established. Rarely does a book so fully reorganize how we think about our place in the universe. We are on the threshold of a new understanding—of where we are in the cosmos, and what we are made of.