The title of this book brings to mind topics such as the Copenhagen Interpretation, Shrodinger's Cat, the EPR Paradox and Bell's Theorem. Certainly all of these are there, but there is much more. Starting with the Logic of Plato and Aristotle, the reader is guided through the Classical Philosophy of Knowledge. This is unfamiliar territory for most physicists; in fact I found the first four chapters (of a total of 16) quite difficult for someone untrained in philosophical discipline. Then comes a discussion of the formal logic of Mathematics - much more familiar ground this, to be enjoyed and savoured. Quite fascinating and original is the 'Orchard Analogy' in which the author invites us to imagine the Universe as a vast field sprinkled with countless trees representing all conceivable propositions. Some of these trees, the axioms, are the source of the water of Truth. The rules of logic determine a network of channels to carry water from tree to tree. This Truth will flow from the source (the axioms) to irrigate progressively the whole propositional field. Formal Physics enters at chapter 7, with a discussion of the concepts of Special and General Relativity and Quantum Theory. The Schrodinger Cat makes its appearance and is analysed in full in terms of Decoherence, which destroys quantum interference at macroscopic level. Again there are moments of light relief: I liked the classical example of non-commuting operators - the result is different when you boil potatoes and then crush, compared to crushing first and then boiling! Next comes our change of attitude towards `Physical Reality' in the context of Quantum Mechanics. The author argues that the counter-intuitive concepts of 'Quantum Reality' and the correlation of measurements of widely separated quantum systems are a fact of Nature, puzzling to 'common sense', but not at variance with logic. The final two chapters offer `some trails towards a Wide or Grand Realism' and a new Philosophy of Knowledge. Intelligibility and locality become `properties' valid at macroscopic level - the level of our senses. In summary I found that this book has broadened my awareness of some very deep philosophical concepts, and has given a new insight into topics such as Knowledge, Reality and Logic. I recommend it to all `natural philosophers' as a source of enjoyment and food for thought.
The title of this book brings to mind topics such as the Copenhagen Interpretation, Shrodinger's Cat, the EPR Paradox and Bell's Theorem. Certainly all of these are there, but there is much more. Starting with the Logic of Plato and Aristotle, the reader is guided through the Classical Philosophy of Knowledge. This is unfamiliar territory for most physicists; in fact I found the first four chapters (of a total of 16) quite difficult for someone untrained in philosophical discipline. Then comes a discussion of the formal logic of Mathematics - much more familiar ground this, to be enjoyed and savoured. Quite fascinating and original is the 'Orchard Analogy' in which the author invites us to imagine the Universe as a vast field sprinkled with countless trees representing all conceivable propositions. Some of these trees, the axioms, are the source of the water of Truth. The rules of logic determine a network of channels to carry water from tree to tree. This Truth will flow from the source (the axioms) to irrigate progressively the whole propositional field. Formal Physics enters at chapter 7, with a discussion of the concepts of Special and General Relativity and Quantum Theory. The Schrodinger Cat makes its appearance and is analysed in full in terms of Decoherence, which destroys quantum interference at macroscopic level. Again there are moments of light relief: I liked the classical example of non-commuting operators - the result is different when you boil potatoes and then crush, compared to crushing first and then boiling! Next comes our change of attitude towards Physical Reality' in the context of Quantum Mechanics. The author argues that the counter-intuitive concepts of 'Quantum Reality' and the correlation of measurements of widely separated quantum systems are a fact of Nature, puzzling to 'common sense', but not at variance with logic. The final two chapters offer some trails towards a Wide or Grand Realism' and a new Philosophy of Knowledge. Intelligibility and locality become properties' valid at macroscopic level - the level of our senses. In summary I found that this book has broadened my awareness of some very deep philosophical concepts, and has given a new insight into topics such as Knowledge, Reality and Logic. I recommend it to all natural philosophers' as a source of enjoyment and food for thought.
In this magisterial work, Roland Omnès takes us from the academies of ancient Greece to the laboratories of modern science as he seeks to do no less than rebuild the foundations of the philosophy of knowledge. One of the world's leading quantum physicists, Omnès reviews the history and recent development of mathematics, logic, and the physical sciences to show that current work in quantum theory offers new answers to questions that have puzzled philosophers for centuries: Is the world ultimately intelligible? Are all events caused? Do objects have definitive locations? Omnès addresses these profound questions with vigorous arguments and clear, colorful writing, aiming not just to advance scholarship but to enlighten readers with no background in science or philosophy. The book opens with an insightful and sweeping account of the main developments in science and the philosophy of knowledge from the pre-Socratic era to the nineteenth century. Omnès then traces the emergence in modern thought of a fracture between our intuitive, commonsense views of the world and the abstract and--for most people--incomprehensible world portrayed by advanced physics, math, and logic. He argues that the fracture appeared because the insights of Einstein and Bohr, the logical advances of Frege, Russell, and Gödel, and the necessary mathematics of infinity of Cantor and Hilbert cannot be fully expressed by words or images only. Quantum mechanics played an important role in this development, as it seemed to undermine intuitive notions of intelligibility, locality, and causality. However, Omnès argues that common sense and quantum mechanics are not as incompatible as many have thought. In fact, he makes the provocative argument that the "consistent-histories" approach to quantum mechanics, developed over the past fifteen years, places common sense (slightly reappraised and circumscribed) on a firm scientific and philosophical footing for the first time. In doing so, it provides what philosophers have sought through the ages: a sure foundation for human knowledge. Quantum Philosophy is a profound work of contemporary science and philosophy and an eloquent history of the long struggle to understand the nature of the world and of knowledge itself.
It is very likely that most readers and authors of articles appearing in Classical and Quantum Gravity are interested in what might loosely be termed the philosophy of science. It is equally likely, with perhaps a few exceptions, that the research of these same readers and authors has not been influenced in the least by the work of professional philosophers of science. This is certainly the case for those of us who work in quantum field theory. One must therefore ask who the intended audience is for a book which purports to discuss the philosophical implications of quantum field theory. In the preface, the author states that there are two intended audiences for his book. The first is `other interested interpreters of physics' who wish to learn something about quantum field theory in as painless a way as possible. The second is for students of physics who are bogged down in the details of learning quantum field theory and cannot see the overall picture. I am not convinced that either audience will find this book to be of much use. There are two basic problems with this book. The first is that the quantum field theory in it is of the old-fashioned kind, and is not really representative of the way the subject is either taught or thought of today. The second is that there is not sufficient background material present to make this book suitable for a novice reader. For example, I wonder how much a reader who has not studied quantum mechanics in any depth will get out of a treatment which launches into Hilbert space and a discussion of states without much in the way of proper introduction. Any reader who is familiar with the workings of quantum field theory will find much to disagree with in this book. For example, the author tries to make a case that a Fock space description is better than talking about particle labels and restricting to symmetric or antisymmetric states. The reason claimed for this is that there are states in Fock space which are neither symmetric nor antisymmetric under particle interchange which must be discarded. (In the author's words, this introduces `surplus formal structure'.) However, in Fock space an equally arbitrary choice is made by focusing on relations among the creation and annihilation operators which involve only commutation or anticommutation relations. Although this is acknowledged by Teller, no satisfactory explanation is given as to why one procedure is any less arbitrary than the other. The book is incomplete in many ways, with many interesting points mentioned just in passing. For example, the discussion around the Newton--Wigner position operator would have been greatly enhanced by including more details, such as an explanation as to why quanta described by Newton--Wigner states seem to propagate at superluminal speeds. It is hard to believe that a reader who has not met the Rindler vacuum before would find Teller's discussion to be very informative. After being so critical of this book, I should mention a part which I did enjoy and would recommend to students of physics. This is the last chapter of the book which contains a discussion of renormalization theory. It is my experience that students often find renormalization theory confusing, and may find Teller's semiqualitative discussion illuminating.
By questioning the validity of some of our basic concepts, such as space, object, and causality, quantum physics contributes quite decisively to the dramatic changes now taking place in our world picture.This book is addressed not only to physicists at an early stage in their careers (the first or second year graduate student) but also to philosophers, as well as to all the senior physicists interested in the interpretation problem. Beginning with a chapter that could be described as ?philosophy for physicists,? it presents an in-depth analysis of present-day quantum mechanical concepts, an analysis of physicists and philosophers alike. Specifically, it first offers an extensive critical analysis of such topics as the Einstein, Podolsky, Rosen reality criterion, nonseparatability, the quantum measurement riddle, decoherence theory, consistent histories approaches and ontologically interpretable theories. All this then naturally leads to philosophical questions concerning, in particular, intersubjective agreement and the limit of realism. And a thorough examination of this whole material finally leads to the view that distinguishing between empirical reality and a veiled man-independent reality yields an acceptable answer to the perplexing question of how to interpret quantum physics. Veiled Reality offers nonspecialists, including students in physics, philosophy and the history of science, an accessible perspective on basic problems in the foundations of physics.
The relation between Physics and Philosophy brings to mind the proverbial marriage of high drama; the parties do not approve of each other, but separated they cannot live. Philosophers find physicists shallow, and many physicists claim that they find philosophic speculations useless or worse. Mostly both display a lack of knowledge and understanding of the methods and goals of the other. A few researchers have tried to bridge this gap and explore the worlds of both parties. Michael Redhead has worked in this borderland, and when he retired from his chair in Cambridge, a symposium was arranged to honour him. The talks presented on this occasion are now published in a volume presenting much food for thought to both philosophers and physicists. The essays in this publication do not offer easy reading; not too many readers will have the preparation to penetrate the technical arguments offered. The authors are well acquainted with both philosophical argumentation and mathematical formalism, and, following the lead of Professor Redhead, they combine these in intricate and suggestive ways. Only a close reading can offer understanding of the points of view taken by the various authors. Browsing and mere reading defines the scenery, exploring it demands much more. Many of the nine essays included investigate the meaning of terms used loosely in physics contexts: locality, beables, symmetries and time in relativity. All essays utilize the mathematical structures of physics, but the approach is mainly philosophical; concepts like reality and metaphysics are applied. Some writings are more physical in their treatment of technical questions relating to modern quantum theory. Bohmian mechanics, localized quantum states and gauge symmetries are discussed in detail. It is, however, found that these present interpretational problems that are usually glossed over in purely physical treatments. For an old sceptic like myself, it is quite refreshing to find that many assertions, taken for granted in our textbooks, are indeed doubtful and offer conceptual or technical difficulties. This insight is what a philosophical analysis can offer the working physicist; future progress may well arise from such realizations. However, the results offered by philosophical analysis are usually found unsatisfactory; the hope that philosophy can suggest novel directions for the theory remains unfounded. Philosophers can learn that modern physics rests on a very shaky conceptual foundation. The theory has evolved by a combination of serendipity and opportunism. The beast that finally has emerged is neither well founded nor internally consistent. Its only merit is that it works. That offers the ultimate philosophical problem of modern physics. If the present book can help the philosopher to behold this challenging but overwhelming wilderness, then it serves a useful purpose indeed. But the prospective researcher has to learn to master the difficult language used by the natives, who are not always friendly. I enjoyed reading the book immensely, but the technical difficulty of the text made my understanding remain mostly superficial. I hope to have the time to return some of the essays, and look into the references and issues involved. The work is genuinely what it promises: a guide From Physics to Philosophy .
All men by nature desire to know, states Aristotle in the famous first sentence of his Metaphysics. Knowledge about fundamental particles and interactions, that is, knowledge about the deepest aspects of matter, is certainly high if not top on the priority list, not only for physicists and philosophers. The goal of the present book is to contribute to this knowledge by going beyond the usual presentations of quantum field theory in physics textbooks, both in mathematical approach and by critical reflections inspired by epistemology, that is, by the branch of philosophy also referred to as the theory of knowledge. Hopefully, the present book motivates physicists to appreciate philosophical ideas. Epistemology and the philosophy of the evolution of science often seem to lag behind science and to describe the developments a posteriori. As philosophy here has a profound influence on the actual shaping of an image of fundamental particles and their interactions, our development should stimulate the curiosity and imagination of physicists. This book can be used as a textbook on quantum field theory for students of physics or as a monograph for philosophers and physicists interested in the epistemological foundations of particle physics. The benefits of an approach resting on philosophical foundations is twofold: the reader is stimulated to critical thinking and the entire story flows very naturally, thus removing all the mysteries from quantum field theory.
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.