In the article the concept of complementarity, suggested by Niels Bohr, is considered from the point of view of non-classical gnoseology. It is shown that the subsequent frequently interpreters place complementarity in the object of research. It is emphasized that this point of view contradicts the original idea of Bohr.
The article is devoted to the problem of scientific and philosophical status of complementarity principlef. The author analyzes its explication by N. Bohr and its comprehension by scientists and epistemologists. It is shown that generally, the complementarity principle is a set of ideas, which allows comprehending of specific situation in quantum mechanics. Some of ideas – the role of language of classical physics, the role of macro-instrument, the integrity of scientific experiment, the integrity of micro-object – could be seen as general scientific and epistemological principles. The prohibition of ontologisation of quantum phenomenon, which necessarily leads to contradictions is considered as the semantic core of Bohr’s approach. However, the attempts of its generalization in science and philosophy were not successful. The complementarity postulate is viewed as methodological principle of foundations of quantum mechanics in its Copenhagen interpretation.
Resumo: A nova forma de causalidade estatistica, Niels Bohr deu-lhe o nome de principio da complementaridade, em dois modos de compreender a “natureza fisica”. As relacoes de complementaridade, expressando os limites dos conceitos classicos, pretende apresentar nova leitura sobre os fenomenos atomicos, em termos dos conceitos da fisica classica. Assim, N. Bohr propoe um novo principio de complementaridade. Assim, sera analisada, tanto quanto for possivel, os fundamentos ontologicos, gnoseologicos e as aplicacoes do referido principio da Mecânica Quântica. Palavras-chave: Niels Bohr, principio da complementaridade, mecânica quântica, ontologia, gnoseologia, filosofia e aplicacoes. Summary: To this novel type of statistical causality Bohr gave the name complementarity; the two mutually exclusive modes of description where said to be complementary, and they then conditioned each other in a statistical way. This relation of complementarity, expressing the limitations of the classical concepts, made it possible to give a complete and consistent account of the atomic phenomena in terms of such classical concepts of physics. Bohr stressed the possibility of applying a similar method of analysis to the most varied domains of knowledge, where apparent contradictions resolve themselves into relations of complementarity. According to N. Bohr, there is effort to achieving a more and more precise formulation of the complementarity idea, and to developing its wider ontological or gnoseological implications as soon as possible the phenomenological applications to others sciences, on this article, by the Quantum Mechanics.
Complementarity and Deconstruction: Plotnitsky's Analysis and Beyond Makoto Katsumori Akita University The philosophical thought of the modern physicist Niels Bohr (1885–1962), which revolves around the concept of complementarity, has long been a major subject of historical and philosophical inquiry. Many prior studies of Bohr's complementarity, however, seem to be limited by the fact that they largely proceed within the conceptual frames of the "mainstream" philosophy of science. This being the case, his radical questioning of traditional scientific and philosophical notions—such as the unambiguity of concepts and words—has not been adequately addressed, insofar as these notions are uncritically presupposed by the commentators themselves. In other words, Bohr's thought has often been interpreted under certain tacit premises of scientific rationality that are precisely of the kind targeted by his epistemological critique. In recent years, however, there have emerged new approaches to Bohr's idea of complementarity that place it in different, less conventional, philosophical contexts. Among the most notable of these is Arkady Plotnitsky's endeavor to connect Bohr's complementarity with Jacques Derrida's project of deconstruction. In the present article, based on my recent doctoral dissertation,1 I take up this contribution by Plotnitsky as a suitable point of reference from which to [End Page 435] explore anew Bohr's thought with its radical philosophical implications. After outlining Bohr's complementarity argument and Plotnitsky's reading thereof (in the first and second sections, respectively), I will examine a series of problems that seem to face, or to be left unsolved by, Plotnitsky's account (in the third section). This critical appraisal will finally lead me to sketch a new interpretive approach of my own (in the fourth section), which both extends and delimits the intersections between complementarity and deconstruction. As regards the historical development of Bohr's complementarity, I will largely restrict myself to the period between 1927 and 1950, in which the most crucial of his innovative ideas seem to have been presented. I. Bohr's Idea of Complementarity In his 1927 lecture delivered in Como, Italy, entitled "The Quantum Postulate and the Recent Development of Atomic Theory," Niels Bohr introduced the concept and framework of complementarity as a pivotal idea in his interpretation of quantum theory. From then on, he continually developed the idea of complementarity with regard not only to quantum theory but to other fields of knowledge as well. In what follows, I will first outline his complementarity argument in its "early" period, stretching from 1927 to the mid-thirties,—or, more precisely, until just before his 1935 debate with EPR.2 Bohr starts by noting that "our usual description of physical phenomena is based entirely on the idea that the phenomena concerned may be observed without disturbing them appreciably."3 This notion of physical phenomena as undisturbed by observation underlies all of classical physics and is still maintained in the theory of relativity. However, Bohr continues, a new situation has arisen with the development of quantum theory, specifically with "the so-called quantum postulate, which attributes to any atomic process an essential discontinuity, or rather individuality, completely foreign to the classical theories"; this "individuality" implies that "any observation of atomic phenomena will involve an interaction with the [End Page 436] agency of observation not to be neglected" (PWNB, 1: 53–54.). In more specific terms, any observation aimed at space-time coordination brings about an exchange of momentum and energy with the measuring rods and clocks. It is crucial here that this interaction between the object and the instrument of observation is not simply unavoidable, but "uncontrollable," which represents a "feature of irrationality" brought into the description of nature (PWNB, 1: 68, 91). For insofar as the measuring instruments are to fulfill their purpose, the interaction itself cannot be taken into account, and thus the magnitude of the disturbance always remains unknown. It follows, in Bohr's view, that "an independent reality in the ordinary physical sense can neither be ascribed to the phenomena nor to the agencies of observation...
Introduction In order to develop the insight that is worked out by Brock (Niels Bohr's Philosophy of Quantum Mechanics, Logos, 2003), that the philosophy of quantum mechanics should parallel Kant's philosophy of natural science, some preliminary analyses of key concepts need to be done. Initiated by Niels Bohr (Atomic Physics and Human Knowledge, John Wiley and Sons, 1958), the concept of ‘complementarity’ has played a major role in the interpretation of quantum theory. However, the exact place it occupies in respect of the logical form of the relation of complementarity between descriptive predicates has not been spelled out in detail to my knowledge. Complementary predicates exclude one another as simultaneous attributions to the same subject. Exactly what form does this exclusion take? How is it related to the basic exclusion-of-predicates principle, the logical law of non-contradiction?
This article explores Bohr's argument, advanced under the heading of 'complementarity,' concerning quantum phenomena and quantum mechanics, and its physical and philosophical implications.In Bohr, the term complementarity designates both a particular concept and an overall interpretation of quantum phenomena and quantum mechanics, in part grounded in this concept.While the argument of this article is primarily philosophical, it will also address, historically, the development and transformations of Bohr's thinking, under the impact of the development of quantum theory and Bohr's confrontation with Einstein, especially their exchange concerning the EPR experiment, proposed by Einstein, Podolsky and Rosen in 1935.Bohr's interpretation was progressively characterized by a more radical epistemology, in its ultimate form, which was developed in the 1930s and with which I shall be especially concerned here, defined by his new concepts of phenomenon and atomicity.According to this epistemology, quantum objects are seen as indescribable and possibly even as inconceivable, and as manifesting their existence only in the effects of their interactions with measuring instruments upon those instruments, effects that define phenomena in Bohr's sense.The absence of causality is an automatic consequence of this epistemology.I shall also consider how probability and statistics work under these epistemological conditions.