In this final chapter, we systematically examine and synthesize the key conclusions derived from the previous parts, while also proposing several important and interesting directions for future research that could extend our current topics. Specifically, we highlight (1) generalizations and variants of the historicized ontology, including the coevent formalism or quantum measure theory, the superdensity operators formalism, and the pseudo-density matrix formalism; (2) the physical extension of the application of quantum histories formalism, such as open quantum systems, infinite-dimensional cases, and classical/quantum relativity, and some interpretational and philosophical reflections. Finally, we give some remarks from the methodological perspectives for future foundational research of quantum mechanics.
In this final chapter, we systematically examine and synthesize the key conclusions derived from the previous parts, while also proposing several important and interesting directions for future research that could extend our current topics. Specifically, we highlight (1) generalizations and variants of the historicized ontology, including the coevent formalism or quantum measure theory, the superdensity operators formalism, and the pseudo-density matrix formalism; (2) the physical extension of the application of quantum histories formalism, such as open quantum systems, infinite-dimensional cases, and classical/quantum relativity, and some interpretational and philosophical reflections. Finally, we give some remarks from the methodological perspectives for future foundational research of quantum mechanics.
This book discusses the ontology in the quantum world and argues that it should be interpreted as a historicized ontology. This perspective is advocated by the quantum histories interpretation. Inspired by the nomological interpretation from Bohmian mechanics and the corresponding understanding of the law of nature and logic, the ontology will be useful to solve the difficulties of confusing ontology and perplexing logical inference. Furthermore, this book proposes that the historicized ontology can be generalized to more complicated structures and fit naturally into temporal correlation. Core philosophical issues such as the law of nature, the ontology of events, history, and processes, and the metaphysics of history are coherently discussed, revealing the profound meaning behind the formalism of quantum histories. By providing a new framework for a historicized picture of ontology, it will effectively promote the debates in the philosophy of physics and the fundamental research in quantum mechanics. This book will appeal to scholars and students of the philosophy of science, metaphysics, and quantum theory.
Quantum mechanics approaches its centenary with an impressive record. It became the backbone of most research in physics, led to applications such as the transistor and laser, and prompted an upheaval in the philosophy of science. Its scope and its precision have been constantly growing, and it is now promising more powerful computers and safer cryptography. This century of conquests has also been a time of ongoing debates about the foundations and interpretation of the theory, which has been referred to as the quantum controversy. The controversy has been unusually long and remains open. Jammer called it “a story without an ending” and Laloë described this coexistence of successes and doubts with the metaphor of the colossus with feet of clay. This Handbook is a survey on this history. Some of the so-called “interpretations” are not interpretations of a fixed formalism, they are different theories, thus it has been a debate about the interpretations and the foundations of quantum mechanics. In this volume, the “history of interpretations” is used for the sake of brevity. The successive parts of the Handbook deal with the scientific and philosophical issues under debate, historical landmarks, places and contexts, historical and philosophical theses, and the proliferation of interpretations. This Handbook may serve those interested in the history of quantum mechanics and those who are engaged with, or attracted by current research on quantum information, as it may give them a flavor of the history that led to or lay the groundwork for the current investigations.
This chapter, along with the next two chapters, sets the basic context for the readers to go into the topic of this book. Physicists, mathematicians, and philosophers struggle to clarify the foundations of quantum mechanics and debate on the interpretations of quantum mechanics. What is the foundation of quantum mechanics and how to interpret the formalism of quantum mechanics are the core issues of concern in the philosophy of physics. These two questions also involve fundamental issues in the general philosophy of science and even metaphysics and epistemology. This chapter introduces the original thoughts, historical developments, and current status of the interpretation of quantum mechanics, as well as its connection with the philosophy of science and metaphysics; it also analyzes the classifications by Bell, Leifer, and Cabello on the spectrum of interpretations of quantum mechanics, which can be regarded as a sort of “navigation map”. On this basis, the main object of discussion in this book is introduced – the quantum histories interpretation.
This chapter presents some concluding thoughts from the authors. It evokes future prospects and mentions the challenges ahead. It addresses questions such as: How far will the industry of thought experiments be carried and the quantum classical boundary pushed back? What are the odds to beat decoherence and make quantum information practical? What are the best systems to achieve these goals? Should they be reached from bottom-up, as in atomic physics, or from top-down, as in condensed matter physics?
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 background for this book was a shift of interest among experimental physicists that began approximately 20 years ago. The shift was from quantum measurements on large ensembles of microscopic quantum objects, to experiments of very high precision on single, macroscopic objects. This shift was accompanied by developments in the “culture” of such measurements and the invention and elaboration of new experimental methods. In parallel with these experimental developments, there was a noticeable increase of theoretical interest in the foundations and interpretation of quantum theory, and even in attempts to revise its foundational principles. Although these efforts have not produced any significant changes in the fundamental structure of quantum theory, they have revealed a rather large number of “blank spots” and unsolved problems, to which the founders of quantum physics had paid no attention. A reasonable number of the blank spots have been filled in during the past decade. The reader has probably noticed that this book can be divided into two parts. In the first (chapters I―VII and XI), the authors have tried to present the modern approach to the quantum theory of measurement. This part can be regarded as a tutorial appendix to textbooks for advanced undergraduate or graduate-level courses in quantum mechanics, where little attention is usually paid to measurement theory.