Philosophy of science and, more specifically, philosophy of quantum physics can be but special fields of a general philosophy of knowledge; and the problems arising in these fields can be evaluated properly only when they are seen under the perspective of the whole range of human knowledge. This paper deals with problems of quantum physics and, in particular, with the problem of scientific objects in quantum physics from the epistemological point of view previously defined in the author's books, A Philosophy of Science (1940) and The Basis and Structure of Knowledge (1948). The argument of the paper, however, has not been stated before in the direct and concise manner here attempted and may therefore contain elements of novelty even for those readers who are familiar with the books just mentioned.
Philosophy of science and, more specifically, philosophy of quantum physics can be but special fields of a general philosophy of knowledge; and the problems arising in these fields can be evaluated properly only when they are seen under the perspective of the whole range of human knowledge. This paper deals with problems of quantum physics and, in particular, with the problem of scientific objects in quantum physics from the epistemological point of view previously defined in the author's books, A Philosophy of Science (1940) and The Basis and Structure of Knowledge (1948). The argument of the paper, however, has not been stated before in the direct and concise manner here attempted and may therefore contain elements of novelty even for those readers who are familiar with the books just mentioned.
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.
While philosophy of science is the study of problems of knowledge concerning science in general, there also exists - or should exist - a '' philosophy in science'' directed at finding out in what ways our actual scientific knowledge may validly contribute to the basic philosophical quest. Contrary to philosophy of science, which is a subject for philosophers, philosophy in science calls on the services of physicists. When, in its spirit, quantum theory and Bell's theorem are used as touchstones, the two main traditional philosophical approaches, realism and idealism, are found wanting. A more suitable conception seems to be an intermediate one, in which the mere postulated existence of a holistic and hardly knowable Mind-Independent Reality is found to have an explaining power. Some corrections to comments by Schins of a previous work on the same subject are incorporated.
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.
The previous chapters contain many examples of the successful application of quantum mechanics to the solution of real physical problems. These represent only a small sample of the wide range of experimental results, spanning just about all areas of physics and chemistry and beyond, that have been successfully explained by quantum theory. So far at least, no quantum-mechanical prediction has been experimentally falsified. Despite these successes, however, many scientists have considered the basic conceptual framework of the subject to be unsatisfactory, and repeated attempts have been made to reinterpret quantum mechanics, or even replace it with a different theory whose philosophical and conceptual basis could be considered more acceptable. In the present chapter we shall explain the reasons for this dissatisfaction and outline some of the reinterpretations and alternative approaches that have been devised. Inevitably many of the questions that arise in this area are matters of opinion rather than fact and, for this reason, some physicists consider that they belong more properly to the realm of philosophy than of physics. However, the conceptual basis of quantum mechanics is so fundamental to our whole understanding of the nature of the physical universe that it should surely be important for physicists to understand the nature of the problems involved, if nothing else.1,2 16.1 THE CONCEPTUAL PROBLEMS In this section we outline some of the main areas of difficulty with a view to more detailed discussion later in the chapter.
It is widely accepted that consciousness at the start of the 20th century was considered mainly in the context of neurology and the mind-body problem belonged to the domain of neuroscience, psychology and philosophy, later broadened by behavioural science and cognitive science. However, these disciplines cannot completely explain the correlation between mental activity and matter. \nChapter one starts by defining the difficulty of determining consciousness. A discussion of how philosophers (such as Descartes, Locke, Dennett and Nagel) attempted to describe this phenomenon leads to the conclusion that firstly, consciousness is indefinable and secondly, it continues to be a challenge for both – philosophy and science – to explain how subjective consciousness fits into the objective world. The following two parts of the chapter focus on the major philosophical theories of the mind-body problem. \nIn chapter two there is a focus on the mutual relation between philosophy and science, physics in particular. However, this project deals more with the implications of science for the philosophy of mind and mind-body problem than the science itself. The second enquiry of this chapter is to point out the difference in philosophical and scientific understanding of the word ‘substance’ (crucial to the mind-body problem). \nChapter three considers quantum theory, since the relation between mind and body started to be tackled from the completely new point of view, after the philosophers began to assimilate the implications of quantum physics. Firstly, there is a short introduction to quantum theory and the most significant points for philosophy and quantum mechanics issues are provided (such as quantum superposition, the measurement problem or the backward causation). Analysis of three prevailing theories is provided. \nThis project addresses the contribution of quantum mechanics to the studies of consciousness and matter and examines whether it helps in solving the mind-body problem.
This book deals with the 'crisis of objectivity' and the 'crisis of realism' which overtook physics when Heisenberg and Bohr consciously rejecting the intentionality-structure of classical physics, gave physics a new form and a new philosophy. The new physics was called quantum mechanics and the new philosophy was called complimentarity. Using the method 'analysis of horizons,' the author attempts to disentangle the epistemological and ontological pesuppositions of Heisenberg's view of complementarity. A similar analysis of Bohr's view of complimentarity reveals a remarkable contrast in basic philosophy between the two founders of quantum physics. The author distinguishes various kinds of objectivity and realism and discusses critically the different aspects of the crisis that emerges in the quantum theory of measurement, the indeterminacy relations and in the statistical and causal structure of quantum mechanics. Heisenberg's formulation of the crisis is reduced to the underlying presuppositions of his thought. These presuppositions are criticised and shown to be defective. A more nuanced epistemological analysis reveals that quantum mechanics answers in a specially beautiful way to the full exigencies of the human mind and its knowledge of concrete reality.