This paper argues against the possibility of presenting a consistent version of the Copenhagen Interpretation of Quantum Physics, characterizing its founders' philosophical pronouncements including those on the realism-antirealism issue, as a contingent collection of local, often contradictory, moves in changing theoretical and sociopolitical circumstances. The paper analyzes the fundamental differences of opinion between Bohr and the mathematical physicists, Heisenberg and Born, concerning the foundational doctrine of the “indispensability of classical concepts”, and their related disagreements on “quantum reality.” The paper concludes with an explanation of how the appearance of consensus was achieved despite fundamental disagreements among the proponents. The paper undermines the adequacy of the notion of a general conceptual framework to describe the philosophical endeavors of working scientists.
This paper argues against the possibility of presenting a consistent version of the Copenhagen Interpretation of Quantum Physics, characterizing its founders' philosophical pronouncements including those on the realism-antirealism issue, as a contingent collection of local, often contradictory, moves in changing theoretical and sociopolitical circumstances. The paper analyzes the fundamental differences of opinion between Bohr and the mathematical physicists, Heisenberg and Born, concerning the foundational doctrine of the “indispensability of classical concepts”, and their related disagreements on “quantum reality.” The paper concludes with an explanation of how the appearance of consensus was achieved despite fundamental disagreements among the proponents. The paper undermines the adequacy of the notion of a general conceptual framework to describe the philosophical endeavors of working scientists.
Abstract The confrontation between Einstein and Bohr over the interpretation of quantum theory has been painted in the past as a direct conflict between realism and positivism. However, more recent attempts to uncover the philosophical positions of both Einstein and Bohr have revealed that these were not so black and white. Einstein’s realism was conditioned by the strong empiricist influence in his own early experiences as a theorist and the growing wariness that led him eventually to reject Machian positivism. His was a realism born of a sense of necessity: a belief that a realist stance is the only one that leads to productive theorizing about the physical world. Bohr’s philosophy went through some quite marked changes, principally in response to Einstein’s challenges. The father of modem atomic theory could hardly subscribe to an uncompromising positivist position that rejected the reality of atoms. But the reality of the inner workings of those atoms was, Bohr contended, beyond the reach of a knowledge founded on complementary classical concepts of waves and particles. As Einstein’s challenges became deeper and more subtle, so Bohr’s position shifted to that of a distinctive anti-realism. Add to this a rhetoric in Bohr’s speeches and published writings that insisted on the logical inevitability of the Copenhagen interpretation, that insisted on its status as the only feasible interpretation, and that countenanced no other alternative, and you have dogma in the making. Heisenberg called it ‘Kopen hagener Geist der Quantentheorie’, the Copenhagen spirit of quantum theory which, he declared in 1930, ‘has directed the entire development of modem atomic physics’. Einstein frequently referred to the Copenhagen doctrine as ‘Talmudic’.
This article examines the epistemological views of key quantum physicists of the Copenhagen circle (Niels Bohr, Werner Heisenberg and Léon Rosenfeld). The discussion begins with a presentation of their conception of measurement, indeterminacy and complementarity, and goes on to focus on their views regarding the nature of being and knowledge. The author identifies the basic areas of consensus in the Copenhagen circle as well as the disagreements and disputes that arose between its members. Three main points are argued: (1) The fundamental epistemological consensus in the group was that subject and object are inseparable; that the subject participates in the formation of images of reality, which are multiple and depend on how the subject is concretely constituted historically; the disagreements within the group did not arise with logical inevitability from the principles of quantum mechanics but largely stemmed from ideological clash in the Cold War context. (2) Being linked to specific configurations of the subjects, knowledge is always relative; but it does not follow that knowledge is illusory or inadequate; on the contrary, it is the pretension of attaining the ultimate nature of things “in themselves” that leads to devaluation of any concrete knowledge. (3) The world is something external, generally independent of our desires and will, but at the same time is constructed as concrete objects through the specific configuration of each concrete subject.
Theological engagement with quantum physics has, to this day, been dominated by the Copenhagen interpretation. However, philosophers and physicists working in the “quantum foundations” field have largely abandoned the Copenhagen view on account of what is widely seen as its troublesome antirealism. Other metaphysical approaches have come to the fore instead, which often take a strongly realist flavor, such as de Broglie‐Bohm, or Everett's “Many‐Worlds” interpretation. In the spirit of recent quantum foundations work, this article introduces a collection of studies aimed at taking quantum theology “beyond Copenhagen.” The present article advocates a commitment to “quantum fundamentalism,” which could resolve some of the enduring ontological problems faced by existing theological work with quantum mechanics, especially in discussions of quantum special divine action. Taking quantum fundamentalism literally would mean a departure from the Copenhagen interpretation, and the article suggests the need for a new research program to lay the groundwork in the natural theology of quantum foundations.
Heisenberg is one of the founders of quantum mechanics, and one of the pioneers and intellectual leaders of the Copenhagen interpretation of quantum mechanics. He proposed in two seminal papers in 1925 and 1927, the fundamentals of matrix mechanics (1925) as the first formalism of quantum mechanics, and then the uncertainty relations (1927) as one of the essential components of the Copenhagen interpretation. The purpose of this paper is to formulate Heisenberg's philosophical approaches during the formation of quantum mechanics and its Copenhagen interpretation. The main question of the paper is whether philosophical approaches can be formulated in the development of quantum mechanics through Heisenberg's works? To answer this question, two seminal papers by Heisenberg (1925 and 1927) are examined. The research method of the paper is based on the content analysis of the text (physics) of Heisenberg's papers. The findings of this study show that three crucial principles - observability, correspondence, and analogy-can be formulated from Heisenberg's 1925 paper, which has played a key role in the formation of the fundamentals of matrix mechanics. Moreover, from his 1927 paper, some issues are addressed including interpretation, understanding and classical-quantum relation, the role of experience and measurement, the subject of causality, as well as reality. Finally, it is concluded that through these works of Heisenberg, four philosophical approaches can be formulated including empiricism, Unificationism, indeterminism, and anti-causality, as well as anti-realism, which themselves include other sub-approaches.
The Argument The aim of this paper is to provide a critical perspective for Einstein's opposition to the Copenhagen interpretation of quantum physics, by analyzing the ingenious rhetoric of Bohr's principle of complementarity. I argue that what Bohr presents as arguments of “inevitability” are in fact merely arguments for the consistency of the quantum-mechanical scheme. Einstein's resistance to being persuaded by this potent technique of argumentation, and his rejection of Bohr's interpretation of quantum physics, appear consequently as an eminently reasonable position and not as a conservative stand, as it is often presented by the adherents of the Copenhagen orthodoxy.
Many of the pioneers of quantum mechanics – notably Planck, Einstein, Bohr, de Broglie, Heisenberg, Schrodinger, Born, Jordan, Landé, Wigner, and London – were seriously concerned with philosophical problems. In each case one can ask a question of psychological and historical interest: was it a philosophical penchant which drew the investigator towards a kind of physics research which is linked to philosophy, or was it rather that the conceptual difficulties of fundamental physics pulled him willynilly into the labyrinth of philosophy? I shall not undertake to discuss this question, but shall cite an opinion of Peter Bergmann, which I find congenial: he learned from Einstein that “the theoretical physicist is … a philosopher in workingman's clothes” ([1], q. v.). The problems with which I am preoccupied concern the philosophical implications of quantum mechanics – either epistemological, bearing on the extent, validity, and character of human knowledge; or metaphysical, bearing on the character of reality. Although quantum mechanics is not a system of philosophy, one can wonder whether it is susceptible to coherent incorporation in a philosophical system. I propose to examine the thought of three masters of quantum mechanics – Bohr, Heisenberg, and Schrödinger – not with a critical or historical intention, but in hope of finding some enlightenment concerning the problems posed by contemporary physics. I can say in advance that enlightenment will continue to elude us; nevertheless, the ideas of Bohr, Heisenberg and Schrödinger are rich and evocative for new studies.