Quantum physics is not mystifying. Its implications may be mind-bending, and not yet fully understood, but the theory is illuminating. It is the best explanation of reality we have. And no, God does not play dice with the universe. Spanning the history of quantum discoveries, from Einstein and Bohr to the present day, this is the essential guide to the most intriguing subject in science. Carroll debunks the myths that have grown up around quantum physics, resurrects and reinstates the Many-Worlds Interpretation, and presents a new path to solving the apparent conflict between quantum mechanics and gravity. A magisterial tour, Something Deeply Hidden encompasses the cosmological and everyday implications of quantum reality. And, finally, it all makes sense.
Quantum physics is not mystifying. Its implications may be mind-bending, and not yet fully understood, but the theory is illuminating. It is the best explanation of reality we have. And no, God does not play dice with the universe. Spanning the history of quantum discoveries, from Einstein and Bohr to the present day, this is the essential guide to the most intriguing subject in science. Carroll debunks the myths that have grown up around quantum physics, resurrects and reinstates the Many-Worlds Interpretation, and presents a new path to solving the apparent conflict between quantum mechanics and gravity. A magisterial tour, Something Deeply Hidden encompasses the cosmological and everyday implications of quantum reality. And, finally, it all makes sense.
Quantum physics is not mystifying. Its implications may be mind-bending, and not yet fully understood, but the theory is illuminating. It is the best explanation of reality we have. And no, God does not play dice with the universe. Spanning the history of quantum discoveries, from Einstein and Bohr to the present day, this is the essential guide to the most intriguing subject in science. Carroll debunks the myths that have grown up around quantum physics, resurrects and reinstates the Many-Worlds Interpretation, and presents a new path to solving the apparent conflict between quantum mechanics and gravity. A magisterial tour, Something Deeply Hidden encompasses the cosmological and everyday implications of quantum reality. And, finally, it all makes sense.
For over nine decades, quantum mechanics has profoundly shaped our understanding of nature, offering explanations for the stability of atoms, the formation of mole cules, the properties of materials, and phenomena such as light or radioactivity. It is essential to modern technologies—from microchips to lasers—and underpins the physics of elementary particles. Yet, despite its successes, it remains a deeply mysterious theory, confronting a central enigma: why does the quantum world behave so differently from everyday reality? Elements such as superposition and quantum entanglement—which allow particles to exist simultaneously in multiple states or remain interconnected regardless of distance—contradict classical world intuitions. This gap between microscopic and macroscopic behavior has given rise to what is known as the “measurement problem,” raising fundamental questions about the nature of reality. Diverging interpretations have led to two major schools of thought: anti-realism, promoted by Niels Bohr, which holds that reality depends on the observer and their interaction with measurement instruments; and realism, supported by Albert Einstein, which argues that quantum mechanics is incomplete and that eality exists independently of observation. Bohr’s complementary philosophy and Heisenberg’s uncertainty principle were central to the formulation of the “Copenhagen interpretation,” which became dominant in the 20th century. However, the persistent opposition of scientists like Einstein and Schrödinger inspired generations of physicists to seek a unification between quantum mechanics and relativity, culminating in new theories such as loop quantum gravity and string theory. Thus, the debate between realism and anti-realism remains alive, and philosophy continues to play a crucial role in exploring the new foundations of physics.
As probably the most successful scientific theory ever created, quantum theory has profoundly changed our view of the world and extended the limits of our knowledge, impacting both the theoretical interpretation of a tremendous range of phenomena and the practical development of a host of technological breakthroughs. Yet for all its success, quantum theory remains utterly baffling. Quantum Reality: Theory and Philosophy, Second Edition cuts through much of the confusion to provide readers with an exploration of quantum theory that is as authoritatively comprehensive as it is intriguingly comprehensible. The book has been fully updated throughout to include the latest results in quantum entanglement, the theory and practical applications of quantum computing, quantum cosmology and quantum gravity. Needing little more than a school level physics and mathematics background, this volume requires only an interest in understanding how quantum theory came to be and the myriad ways it both explains how our universe functions and extends the reach of human knowledge. Written by well-known physics author and teacher Dr. Jonathan Allday, this highly engaging work: • Presents a thorough grounding in the theoretical machinery of quantum physics • Offers a whistle-stop tour through the early part of the 20th century when the founding fathers of quantum theory forever altered the frontiers of human thought • Provides an example-filled interpretation of the theory, its applications, and its pinnacle in quantum field theory (QFT), so crucial in shaping ideas about the nature of reality • Separates fact from speculation regarding quantum physics’ ability to provide a starting point for philosophical queries into ultimate understanding and the limits of science The world beneath the one that we experience with our senses is profoundly mysterious, and while we may never completely unravel that mystery, quantum theory allows us to come closer than ever to understanding where the science leaves off and the mystery begins. Quantum Reality: Theory and Philosophy, Second Edition makes that understanding accessible to anyone possessing a quest for knowledge and a sense of awe.
“Anyone who is not shocked by quantum theory has not understood it.” Since Niels Bohr said this many years ago, quantum mechanics has only been getting more shocking. We now realize that it’s not really telling us that “weird” things happen out of sight, on the tiniest level, in the atomic world. Rather, we can now see that everything is quantum: our everyday world is simply what quantum becomes at the human scale. But if quantum mechanics is right, what seems obvious and right in our everyday world is built on foundations that don’t seems obvious or right—or even possible. An exhilarating tour of the contemporary quantum landscape, Beyond Weird is a book about what quantum physics really means—and what it doesn’t. Science writer Philip Ball offers an up-to-date, accessible account of the quest to come to grips with the most fundamental theory of physical reality, and to explain how its counterintuitive principles underpin the world we experience. Over the past decade it has become clear that quantum physics is less a theory about particles and waves, uncertainty and fuzziness, than a theory about information and knowledge—about what can be known, and how we know it. Discoveries and experiments over the past few decades have called into question the meanings and limits of space and time, cause and effect, and, ultimately, of knowledge itself. The quantum world Ball shows us isn’t a different world. It is our world, and if anything deserves to be called “weird,” it’s us.
The universe we live in is both strange and interesting. This strangeness comes about because, at the most fundamental level, the universe is governed by the laws of quantum mechanics. This is the most spectacularly accurate and powerful theory ever devised, one that has given us insights into many aspects of the world, from the structure of matter to the meaning of information. This textbook provides a comprehensive account of all things quantum. It starts by introducing the wavefunction and its interpretation as an ephemeral wave of complex probability, before delving into the mathematical formalism of quantum mechanics and exploring its diverse applications, from atomic physics and scattering, to quantum computing. Designed to be accessible, this volume is suitable for both students and researchers, beginning with the basics before progressing to more advanced topics.
THOMISM AND THE QUANTUM ENIGMA WILLIAM A. WALLACE, 0.P. University ofMaryland College Park, Maryland THE RECENT PUBLICATION of Wolfgang Smith's The Quantum Enigma: Finding the Hidden Key 1 has done more than propose a novel interpretation of quantum theory. It has also reopened a train of thought that has been somewhat muted in recent decades, namely, that of the relevance of the thought of St. Thomas Aquinas to solving problems raised by modern physics. What I have in mind are books published in the 1950s and 1960s by Jesuit professors at the Gregorian University in Rome 2 and by Vincent Edward Smith in the United States,3 plus my own writings on the subject before I became heavily involved in the history of science.4 Now, out of the blue, as it were, Aquinas's name is once again being invoked in the context of modern science, this time as originating concepts that provide a "hidden key" to the solution of the quantum 1 Peru, Ill.: Sherwood Sugden & Company, Publishers, 1995, iii + 140 pp., with an appendix, a glossary, and an index of names. 2 Especially the following, all published by the Gregorian University Press, Rome: Peter Hoenen, S.J., Cosmologia, 5th ed. (1956); idem, De noetica geometriae (1954); Philip Soccorsi, S.J., De physica quantica (1956); idem, De vi cognitionis humanae in scientia physica (1958); idem, De geometriis et spatiis non-Euclideis (1960). 3 Notably his Philosophical Physics (New York: Harper & Brothers, 1950); and Footnotes for the Atom (Milwaukee: Bruce Publishing Co., 1951). 4 See my"Newtonian Antinomies Against the Prima Via," The Thomist 19 (1956): 15192 ; "The Reality of Elementary Particles," Proceedings of the American Catholic Philosophical Association 38 (1964): 154-66; "St. Thomas and the Pull of Gravity," in Science and the Liberal Concept (West Hartford, Conn.: St. Joseph College, 1964), 14365 ; and "Elementarity and Reality in Particle Physics," Boston Studies in the Philosophy of Science 3 (1968): 236-71. 455 456 WILLIAM A. WALLACE enigma. The author of this startling claim, a professor of mathematics at Oregon State University and apparently no relation to Vincent Edward Smith, surely deserves a hearing in these pages. Wolfgang Smith's thesis is set out in six chapters: the first two, "Rediscovering the Corporeal World" and "What is the Physical Universe?," establish the terms of discourse; the next two, "Microworld and Indeterminacy" and "Materia Signata Quantitate," propose Smith's solution, which basically consists in explaining the significance of state vector collapse in quantum theory; and the last two, "On Whether 'God Plays Dice?"' and "In the Beginning," draw out metaphysical implications of this teaching. An appendix provides a brief mathematical introduction to quantum theory so that the reader can appreciate what is meant by state vector collapse and other technical terms. A glossary gives a handy index of such terms and where they occur in the text. In Smith's view, the devil that needs to be exorcised from contemporary physics is the bifurcationism that took its origin from Rene Descartes, then was reinforced by a succession of philosophers from John Locke to Immanuel Kant (chap. 1). This is the split between res extensa and res cogitans, the first denuding the world of sensible qualities and the second creating the impression that all such qualities (and the nature that underlies them, das Ding an sick) are projected into the universe by the observer. The mind-set such bifurcationism puts into physicists is so strong, and has been reinforced in so many ways by their education and culture, that it is almost impossible for them to recognize it, let alone work at eradicating it. But eradicate it they must if they would solve the enigmas of quantum theory. And the only way they can do so, Smith argues, is by rediscovering the corporeal world. What this means is that they must learn what it is to perceive the world as it presents itself in sense experience, to experience in their own lives the "miracle" of sense perception (16).5 The apple is outside us, but we perceive it nonetheless, with its colors and its other attributes, which are as real as we sense them to be (1-20). 5...