Explicit, quantitative procedures for identifying biodiversity priority areas are replacing the often ad hoc procedures used in the past to design networks of reserves to conserve biodiversity. This change facilitates more informed choices by policy makers, and thereby makes possible greater satisfaction of conservation goals with increased efficiency. A key feature of these procedures is the use of the principle of complementarity, which ensures that areas chosen for inclusion in a reserve network complement those already selected. This paper (...) sketches the historical development of the principle of complementarity and its applications in practical policy decisions. In the first section a brief account is given of the circumstances out of which concerns for more explicit systematic methods for the assessment of the conservation value of different areas arose. The second section details the emergence of the principle of complementarity in four independent contexts. The third section consists of case studies of the use of the principle of complementarity to make practical policy decisions in Australasia, Africa, and America. In the last section, an assessment is made of the extent to which the principle of complementarity transformed the practice of conservation biology by introducing new standards of rigor and explicitness. (shrink)

Es wird der Nachweis versucht, dass es — ebenso wie in der Physik — auch in der Biologie komplementäre Erkenntnissysteme gibt. Wie Welle und Korpuskel in der Physik, so sind innerhalb der Biologie u.a. Form und Funktion, Innenwelt und Umwelt sowie auch vor allem Vererbung und Anpassung komplementäre Begriffsgefüge. Das wird im einzelnen diskutiert und nachgewiesen.Für die Erkenntnis der Wirklichkeit im Ganzen folgt daraus, dass systematisch aufgebaute Erkenntnisgefüge nur in Teilbereichen des Wirklichen möglich sind — nur in der klassischen Mechanik, (...) der Elektrodynamik, der vergleichenden Anatomie, der Genetik usw. — Das Wirkliche in seiner Gesamthet hingegen besitzt keine systematische sondern nur eine historisch-dialektische Struktur. Metaphysisch bedeutet das, dass das Wesen der Wirklichkeit in schöpferischer Freiheit im Sinne etwaGoethes, aber nicht in sturer Notwendigkeit besteht.Se demuestra que — como en laFisica — tambien en la Biologia existen complementarios sistemas de conocimiento. Como onda y corpúsculo dentro de la Fisica, asi son dentro de la Biologia entre otros forma y función, mundo internoy ambientey en primer lugar también herencia y adaptación principios complementarios. Esto será discutido y demonstrado en sus particularidades.Para el conocimiento de la realidad como totalidad sigue de tales consideraciones la conclusión que conocimientos sistematicamente construidos son posibles solo en esferas particulares de la realidad — como p.e. en la mecánica racional, en la electrodinámica, en la anatomia comparada, en la genética etc. —. Lo real en su totalidad posee al contrario ninguna estructura sistemática sino solo un históricadialectica. Metafisicamente hablado significa esto que la esencia de la realidad consiste en una libertad creativa en el sentido deGoethe, pero de ninguna manera en una necesidad absoluta en el sentido deSpinoza. (shrink)

A wide range of problems of the relationship between consciousness and matter are discussed. Particular attention is paid to the analysis of the structure and properties of consciousness in the framework of information evolution. The role of specific (non-computational) properties of consciousness in the procedure of classical and quantum measurements is analyzed. In particular, the issue of "cloning" of consciousness (the possibility of copying its properties onto a new material carrier) is discussed in detail. We hope that the generalized (...) class='Hi'>principle of complementarity formulated by us will open up new ways for studying the problems of consciousness within the framework of the fundamental physical picture of the world. (shrink)

We presented a contextual statistical model of the probabilistic description of physical reality. Here contexts (complexes of physical conditions) are considered as basic elements of reality. There is discussed the relation with QM. We propose a realistic analogue of Bohr’s principle of complementarity. In the opposite to the Bohr’s principle, our principle has no direct relation with mutual exclusivity for observables. To distinguish our principle from the Bohr’s principle and to give better characterization, we (...) change the terminology and speak about supplementarity, instead of complementarity. Supplementarity is based on the interference of probabilities. It has quantitative expression trough a coefficient which can be easily calculated from experimental statistical data. We need not appeal to the Hilbert space formalism and noncommutativity of operators representing observables. Moreover, in our model there exists pairs of supplementary observables which cannot be represented in the complex Hilbert space. There are discussed applications of the principle of supplementarity outside quantum physics. (shrink)

I argue that quantum optical experiments that purport to refute Bohr’s principle of complementarity fail in their aim. Some of these experiments try to refute complementarity by refuting the so called particle–wave duality relations, which evolved from the Wootters–Zurek reformulation of BPC. I therefore consider it important for my forgoing arguments to first recall the essential tenets of BPC, and to clearly separate BPC from WZPC, which I will argue is a direct contradiction of BPC. This leads (...) to a need to consider the meaning of particle–wave duality relations and to question their fundamental status. I further argue that particle and wave complementary concepts are on a different footing than other pairs of complementary concepts. (shrink)

The epistemology of dialectical materialism emphasizes two characteristic features of the picture of the world existing in our minds. First, it presents itself as reflection, i.e., as an image of an objective reality that exists independent of our consciousness. Secondly, this picture provides a reflection of the real world and the regularities of its development that is only approximately complete. The following comment by Lenin is of fundamental significance in this connection: "Cognition is man's reflection of nature, but it is (...) not a simple, not a direct, not a complete reflection, but a process involving a series of abstractions, the shaping and formation of concepts, laws, and the like, various concepts, laws, etc. and embraces, conditionally and approximately, the universal regularity of nature which is eternally moving and developing". (shrink)

The epistemology of dialectical materialism emphasizes two characteristic features of the picture of the world existing in our minds. First, it presents itself as reflection, i.e., as an image of an objective reality that exists independent of our consciousness. Secondly, this picture provides a reflection of the real world and the regularities of its development that is only approximately complete. The following comment by Lenin is of fundamental significance in this connection: "Cognition is man's reflection of nature, but it is (...) not a simple, not a direct, not a complete reflection, but a process involving a series of abstractions, the shaping and formation of concepts, laws, and the like, various concepts, laws, etc. and embraces, conditionally and approximately, the universal regularity of nature which is eternally moving and developing". (shrink)

The mental system of an individual usually generates a reality-model that includes a self-model and a world-model as fundamental components. Exceptional experiences (ExE) can be classified as subjectively experienced anomalies in the self-model or the world-model or in the relation of both. Empirical studies show significant correlations between specific patterns of ExE and socially and clinically relevant variables. In order to examine the ontological status of anomalous phenomena a psychophysical approach is presented in which the principle of complementarity (...) is of fundamental importance. Applying a generalized quantum theory to psychosocial and psychophysical systems, complementary aspects such as autonomy versus reliability or novelty versus confirmation are identified as possible local and global variables. The findings indicate that entanglement correlations could play a role in the occurrence of ExE and that specific psychological interventions can dissolve them. (shrink)

A growing number of commentators have, in recent years, noted the important affinities in the views of Immanuel Kant and Niels Bohr. While these commentators are correct, the picture they present of the connections between Bohr and Kant is painted in broad strokes; it is open to the criticism that these affinities are merely superficial. In this essay, I provide a closer, structural, analysis of both Bohr's and Kant's views that makes these connections more explicit. In particular, I demonstrate the (...) similarities between Bohr's argument, on the one hand, that neither the wave nor the particle description of atomic phenomena pick out an object in the ordinary sense of the word, and Kant's requirement, on the other hand, that both ‘mathematical’ (having to do with magnitude) and ‘dynamical’ (having to do with an object's interaction with other objects) principles must be applicable to appearances in order for us to determine them as objects of experience. I argue that Bohr's ‘complementarity interpretation’ of quantum mechanics, which views atomic objects as idealizations, and which licenses the repeal of the principle of causality for the domain of atomic physics, is perfectly compatible with, and indeed follows naturally from a broadly Kantian epistemological framework. (shrink)

This paper is the sequel of a previous one where we have introduced a paraconsistent logic termed paraclassical logic to deal with 'complementary propositions'. Here, we enlarge upon the discussion by considering certain 'meaning principles', which sanction either some restrictions of 'classical' procedures or the utilization of certain 'classical' incompatible schemes in the domain of the physical theories. Here, the term 'classical' refers to classical physics. Some general comments on the logical basis of a scientific theory are also put in (...) between the text, motivated by the discussion of complementarity. (shrink)

We tentatively propose two guiding principles for the construction of theories of physics, which should be satisfied by a possible future theory of quantum gravity. These principles are inspired by those that led Einstein to his theory of general relativity, viz. his principle of general covariance and his equivalence principle, as well as by the two mysterious dogmas of Bohr's interpretation of quantum mechanics, i.e. his doctrine of classical concepts and his principle of complementarity. An appropriate (...) mathematical language for combining these ideas is topos theory, a framework earlier proposed for physics by Isham and collaborators. Our "Principle of general tovariance" states that any mathematical structure appearing in the laws of physics must be definable in an arbitrary topos (with natural numbers object) and must be preserved under so-called geometric morphisms. This principle identifies geometric logic as the mathematical language of physics and restricts the constructions and theorems to those valid in intuitionism: neither Aristotle's principle of the excluded third nor Zermelo's Axiom of Choice may be invoked. Subsequently, our "Equivalence principle" states that any algebra of observables (initially defined in the topos Sets) is empirically equivalent to a commutative one in some other topos. (shrink)

In this paper, the main outlines of the discussions between Niels Bohr with Albert Einstein, Werner Heisenberg, and Erwin Schrödinger during 1920–1927 are treated. From the formulation of quantum mechanics in 1925–1926 and wave mechanics in 1926, there emerged Born's statistical interpretation of the wave function in summer 1926, and on the basis of the quantum mechanical transformation theory—formulated in fall 1926 by Dirac, London, and Jordan—Heisenberg formulated the uncertainty principle in early 1927. At the Volta Conference in Como (...) in September 1927 and at the fifth Solvay Conference in Brussels the following month, Bohr publicly enunciated his complementarity principle, which had been developing in his mind for several years. The Bohr-Einstein discussions about the consistency and completeness of qnautum mechanics and of physical theory as such—formally begun in October 1927 at the fifth Solvay Conference and carried on at the sixth Solvay Conference in October 1930—were continued during the next decades. All these aspects are briefly summarized. (shrink)

O experimento de Afshar foi proposto recentemente como sendo uma violação do princípio de complementaridade. Reconhecendo a novidade trazida pelo experimento, argumentamos que ele permite um refinamento de tal princípio, a partir do estabelecimento de dois pontos: (1) a possibilidade de modificar o "tipo" de fenômeno (onda ou partícula) sem alterar o estado quântico, e (2) a constatação de que o tipo de fenômeno, associado a um quantum detectado, refere-se a um trecho determinado percorrido pelo objeto quântico. O primeiro ponto (...) é explorado em interferômetros de Mach-Zehnder, com dispositivos de polarização e na montagem dupla de Unruh. O segundo ponto salienta que um fenômeno pode ser corpuscular com respeito a uma região e ondulatório com respeito a outra, estando a novidade de Afshar na proposta de uma maneira de constatar ambos simultaneamente. A restrição (1) acaba tendo um efeito desprezível no experimento de Afshar. Afshar's experiment was recently proposed as a violation of the principle of complementarity. Acknowledging the novelty brought by the experiment, we argue that it allows a refinement of this principle, with the establishment of two points: (1) the possibility of modifying the "type" of phenomenon (wave or particle) without changing the quantum-mechanical state, and (2) the recognition that the type of phenomenon, associated to a detected quantum, refers to a specific region traversed by the quantum object. The first point is explored in Mach-Zehnder interferometers, with polarization devices and in Unruh's double setup. The second point emphasizes that a phenomenon can be corpuscular with respect one region and undulatory with respect to another. Afshar's originality lies in his proposal of a way of ascertaining both simultaneously. Restriction (1) turns out having a negligible effect in Afshar's experiment. (shrink)

Hofstede’s cultural values framework has been applied in a study looking at possible relations between migration streams and their country of destinations. The study is based on a model which consists of three factors: Human Resources Management, Culture Dimensions and Migration and it points out their non-linear relationship. Migration outflows from Poland in 2002 are measured against culture dimensions (both in Poland and destinations countries) and power distance emerges as the most influential possible “pull” factor. A list of positive and (...) negative implications of the Human Resources Management, Migration and Culture Dimensions relationship on a personal, corporate and national level is presented. (shrink)

The term complementarity plays a central role in quantum physics, not least in various approaches to defining entanglement and the conditions for its occurrence. It has, however, been used in a variety of ways by different authors, denoting different concepts and relationships. Here we describe and clarify some of them and analyze the role they play with respect to the phenomenon of entanglement. Based on these considerations we discuss the recently proposed system-theoretical generalization of the concepts entanglement and (...) class='Hi'>complementarity (Atmanspacher et al. in Found Phys 32(3):379–406, 2002; von Lucadou et al. in J Conscious Stud 14(4):50–74, 2007; Filk and Römer in Axiomathes 21(2):211–220, 2011; Walach and Von Stillfried in Axiomathes 21(2): 185–209, 2011). We hope that a clarification regarding the specific meaning of these terms can be useful to the growing engagement with this interesting hypothesis and its critical investigation. (shrink)

The term complementarity plays a central role in quantum physics, not least in various approaches to defining entanglement and the conditions for its occurrence. It has, however, been used in a variety of ways by different authors, denoting different concepts and relationships. Here we describe and clarify some of them and analyze the role they play with respect to the phenomenon of entanglement. Based on these considerations we discuss the recently proposed system-theoretical generalization of the concepts entanglement and (...) class='Hi'>complementarity (Atmanspacher et al. in Found Phys 32(3):379–406, 2002; von Lucadou et al. in J Conscious Stud 14(4):50–74, 2007; Filk and Römer in Axiomathes 21(2):211–220, 2011; Walach and Von Stillfried in Axiomathes 21(2): 185–209, 2011). We hope that a clarification regarding the specific meaning of these terms can be useful to the growing engagement with this interesting hypothesis and its critical investigation. (shrink)

A recent experiment performed by S. Afshar [first reported by M. Chown, New Sci. 183:30, 2004] is analyzed. It was claimed that this experiment could be interpreted as a demonstration of a violation of the principle of complementarity in quantum mechanics. Instead, it is shown here that it can be understood in terms of classical wave optics and the standard interpretation of quantum mechanics. Its performance is quantified and it is concluded that the experiment is suboptimal in the (...) sense that it does not fully exhaust the limits imposed by quantum mechanics. (shrink)

In this paper we adopt a category-theoretic viewpoint in order to analyze the semantics of complementarity for quantum systems. Based on the existence of a pair of adjoint functors between the topos of presheaves of the Boolean kind of structure and the category of the quantum kind of structure, we establish a twofold complementarity scheme which constitutes an instance of the concept of adjunction. It is further argued that the established scheme is inextricably connected with a realistic philosophical (...) attitude, although substantially different from the classical one. (shrink)

Hofstede’s cultural values framework has been applied in a study looking at possible relations between migration streams and their country of destinations. The study is based on a model which consists of three factors: Human Resources Management, Culture Dimensions and Migration and it points out their non-linear relationship. Migration outflows from Poland in 2002 are measured against culture dimensions (both in Poland and destinations countries) and power distance emerges as the most influential possible “pull” factor. A list of positive and (...) negative implications of the Human Resources Management, Migration and Culture Dimensions relationship on a personal, corporate and national level is presented. (shrink)

“Bohr was primarily a philosopher, not a physicist, but he understood that natural philosophy... carries weight only if its every detail can be subjected to the... test of experiment”. As a result his approach differed from that of the school-philosophers whom he regarded with a somewhat “sceptical attitude, to say the least” and whose lack of interest in “the important viewpoint which had emerged during the development of atomic physics” he noticed with regret. But it also differed, and to a (...) considerable degree, from the spirit of what Professor T. S. Kuhn has called a “normal science.” Looking at Bohr's method of research we see that technical problems, however remote, are always related to a philosophical point of view; they are never treated as “tiny puzzles” whose solution is valuable in itself, even if one has not the faintest idea what it means, and where it leads: “For me” Bohr writes to Sommerfeld in 1922 “[the quantum theory] is not a matter for petty didactic details, but a serious attempt to reach... an inner coherence.” Emphasis is put on matters of principle and minor discrepancies, or “puzzles” in the sense of Kuhn, instead of being deemphasized, and assimilated to the older paradigm, are turned into fundamental difficulties by looking at them from a new direction, and by testing their background “in its furthest consequences by exaggeration”. A noteworthy example of Bohr's “non-normal” and rather metaphysical approach to physics is his scepticism in the face of the success of his own atomic model. (shrink)

The ArgumentThe 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. (shrink)

The principle of complementarity in physics can be generalized and extended to information studies. It helps explain the dilemma faced by information studies today. The prevailing endeavor that going beyond the limitation of formal theories and to develop a unified theory of information falls in the dilemma which is structurally homologous to the dilemmas in quantum physics. The dilemma is caused by an epistemological paradox called assignment paradox. The paradox can be removed through generalized complementarity. It means (...) that the concept of information embodying in different theoretical contexts are different phenomenon. They are complementary to each other. The analysis brings bad news to methodologically reductionism and fundamentalism but good news to transdisciplinary approach. (shrink)

We show that Bohr's principle of complementarity between position and momentum descriptions can be formulated rigorously as a claim about the existence of representations of the canonical commutation relations. In particular, in any representation where the position operator has eigenstates, there is no momentum operator, and vice versa. Equivalently, if there are nonzero projections corresponding to sharp position values, all spectral projections of the momentum operator map onto the zero element.

Bohr’s interpretation of quantum mechanics has been criticized as incoherent and opportunistic, and based on doubtful philosophical premises. If so Bohr’s influence, in the pre-war period of 1927–1939, is the harder to explain, and the acceptance of his approach to quantum mechanics over de Broglie’s had no reasonable foundation. But Bohr’s interpretation changed little from the time of its first appearance, and stood independent of any philosophical presuppositions. The principle of complementarity is itself best read as a conjecture (...) of unusually wide scope, on the nature and future course of explanations in the sciences (and not only the physical sciences). If it must be judged a failure today, it is not because of any internal inconsistency. (shrink)

A coherent account of the connections and contrasts between the principles of complementarity and uncertainty is developed starting from a survey of the various formalizations of these principles. The conceptual analysis is illustrated by means of a set of experimental schemes based on Mach-Zehnder interferometry. In particular, path detection via entanglement with a probe system and (quantitative) quantum erasure are exhibited to constitute instances of joint unsharp measurements of complementary pairs of physical quantities, path and interference observables. The analysis (...) uses the representation of observables as positive-operator-valued measures (POVMs). The reconciliation of complementary experimental options in the sense of simultaneous unsharp preparations and measurements is expressed in terms of uncertainty relations of different kinds. The feature of complementarity, manifest in the present examples in the mutual exclusivity of path detection and interference observation, is recovered as a limit case from the appropriate uncertainty relation. It is noted that the complementarity and uncertainty principles are neither completely logically independent nor logical consequences of one another. Since entanglement is an instance of the uncertainty of quantum properties (of compound systems), it is moot to play out uncertainty and entanglement against each other as possible mechanisms enforcing complementarity. (shrink)

The discovery of a letter in the Niels Bohr archives written by Bohr to a Danish schoolteacher in which he reveals his early knowledge of the Daodejing led the present author on a search to unveil the influence of the philosophy of Yin-Yang on Bohr's famed complementarity principle in Western physics. This paper recounts interviews with his son, Hans, who recalls Bohr reading a translated copy of Laozi, as well as Hanna Rosental, close friend and associate who also (...) confirms the influence of ancient Chinese philosophy on this major figure in Western physics. As with Bohr’s dual perspective approach to the wave-particle, in which describing matter as either wave or particle is not considered inherently contradictory, this article likewise argues that Eastern and Western perspectives about philosophy, reality and life in general need not antagonize one another as is the case in Hegelian dialecticism. Through developing a globally accessible, harmonized system of Eastern and Western thought, this article suggests that individuals can more easily overcome limitations arising from cultural singularity in conventional philosophical approaches and, in turn, achieve a greater degree of social harmony and depth of philosophical understanding, all in the same stroke. (shrink)

In this study Arun Bala examines the implications that Niels Bohr's principle of complementarity holds for fields beyond physics. Bohr, one of the founding figures of modern quantum physics, argued that the principle of complementarity he proposed for understanding atomic processes has parallels in psychology, biology, and social science, as well as in Buddhist and Taoist thought. But Bohr failed to offer any explanation for why complementarity might extend beyond physics, and his claims have been (...) widely rejected by scientists as empty speculation. Scientific scepticism has only been reinforced by the naïve enthusiasm of postmodern relativists and New Age intuitionists, who seize upon Bohr's ideas to justify anti-realist and mystical positions. Arun Bala offers a detailed defence of Bohr's claim that complementarity has far-reaching implications for the biological and social sciences, as well as for comparative philosophies of science, by explaining Bohr's parallels as responses to the omnipresence of grown properties in nature. (shrink)

Philosophers have discussed the relationship of cause and effect from ancient times through our own.Prior to the work of Niels Bohr, these discussions presupposed that successful causal attribution implies explanation.The success of quantum theory challenged this presupposition.Bohr introduced a principle of complementarity that provides a new way of looking at causality and explanation. In this succinct review of the history of these discussions, John Losee presents the philosophical background of debates over the cause-effect relation.He reviews the positions of (...) Aristotle, Rene Descartes, Isaac Newton, David Hume, Immanuel Kant, and John Stuart Mill.He shows how nineteenth-century theories in physics and chemistry were informed by a dominant theory of causality and how specific developments in physics provided the background for the emergence of quantum theory. Problems created for the "causality implies explanation" thesis by the emergence of quantum theory are reviewed in detail.Losee evaluates Bohr's proposals to apply a principle of complementarity within physics, biology, and psychology.He also discusses the feasibility of using complementarity as a principle of interpretation within Christian theology.This volume, which includes an in-depth index, is an essential addition to the libraries of advanced undergraduate and graduate students, philosophers, and those interested in causality and explanation. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:Buddhist-Christian Studies 22 (2002) 149-162 [Access article in PDF] Buddhist-Christian Complementarity in the Perspective of Quantum Physics Lai Pan-chiu Chinese University of Hong Kong Introduction The idea of Buddhist-Christian complementarity is by no means new. 1 But what is meant by "complementarity"? In quantum physics, the concept of "complementarity" has been extensively discussed due to the principle of complementarity introduced by Niels Bohr (...) (1885-1962). This principle is also one of the hotly debated issues in the areas of religion and natural science. Many scholars attempt to show that there are cases in Christian theology comparable to the complementarity in quantum physics. The most discussed case is perhaps the Christological doctrine of two natures in Jesus Christ. 2 Some scholars even attempt to interpret the relationship between theology and science in terms of complementarity. 3 This kind of discussion is not merely fanciful imagination originated by Christian theologians, since even Niels Bohr himself did advise Christian theologians to apply the complementary way of thinking in theology. 4 An interesting question may then be whether the principle of complementarity in quantum physics may cast light on the problem concerning Buddhist-Christian complementarity. This is the issue this essay attempts to address. Complementarity in Quantum Physics Modern physics, especially the theory of relativity and quantum physics, as Werner Heisenberg pointed out, brings forth to us an important philosophical issue—the relationship between language and reality. Some modern physicists find that they have to make use of ordinary language to establish a visual understanding or presentation of some events, which can hitherto only be expressed by a bundle of mathematical formulae. However, the ordinary language, together with its derived concepts, used in classical physics cannot adequately interpret some of the discoveries of modern physics. For example, conventional concepts of time and space can no longer apply directly in the general theory of relativity. The inadequacy of the classical concepts of "wave" and "particle" in quantum physics is another illustrative case. According to Bohr's theory, physicists can make use of these classical concepts in a [End Page 149] loose way, even though these concepts may seem to contradict each other when applied together. 5The principle of complementarity proposed by Niels Bohr refers specifically to the use of the two seemingly contradictory concepts in classical physics—"particle" and "wave"—to explain the behavior of a particular entity, light. Wave and particle are mutually exclusive concepts in classical physics. According to the classical understanding, wave possesses some characteristics that particle does not have, such as reflection, refraction, diffusion and interference. In reverse, particle also possesses some characteristics that wave does not have, such as occupying certain space. However, quantum physicists have discovered that in some experiments, light "behaves" as wave, whereas in others it behaves as particle. The results of experiments seem to suggest that neither "wave" nor "particle" can adequately explain the quantum phenomena. For this reason, some physicists, including Albert Einstein, suggest abandoning the use of the concepts of wave and particle in the subatomic realm. Contrary to this view, Bohr insists that the concepts of "wave" and "particle" remain usable and useful in quantum physics because "however far the phenomena transcend the scope of classical physical explanation, the account of all evidence must be expressed in classical terms." 6 As Bohr puts it, "the fundamental postulate of the indivisibility of the quantum of action is itself, from the classical point of view, an irrational element which inevitably requires us to forego a causal mode of description and which, because of the coupling between phenomena and their observation, forces us to adopt a new mode of description designated as complementary in the sense that any given application of classical concepts precludes the simultaneous use of other classical concepts which in a different connection are equally necessary for the elucidation of the phenomena." 7The principle of complementarity can thus be understood as a method or "mode of description" using two or more mutually exclusive concepts of a specific realm (classical physics) to explain a phenomenon of another realm (quantum physics) that... (shrink)

SummaryA short exposition is given of the foundation of the causal description in classical physics and the failure of the principle of causality in coping with atomic phenomena. It is emphasized that the individuality of the quantum processes excludes a separation between a behaviour of the atomic objects and their interaction with the measuring instruments denning the conditions under which the phenomena appear. This circumstance forces us to recognize a novel relationship, conveniently termed complementarity, between empirical evidence obtained (...) under different experimental conditions. An appropriate tool for a complementary mode of description is provided by the quantum‐mechanical formalism which allows us to account for regularities of definite or statistical character beyond the grasp of classical physical explanation. – N. B. (shrink)

The idea of complementarity already appears in William James’ (1890a, p. 206) Principles of Psychology in the chapter on “the relations of minds to other things”. Later, in 1927, Niels Bohr introduced complementarity as a fundamental concept in quantum mechanics. It refers to properties (observables) that a system cannot have simultaneously, and which cannot be simultaneously measured with arbitrarily high accuracy. Yet, in the context of classical physics they would both be needed for an exhaustive description of the (...) system. (shrink)

We report on the simultaneous determination of complementary wave and particle aspects of light in a double-slit type “welcher-weg” experiment beyond the limitations set by Bohr’s Principle of Complementarity. Applying classical logic, we verify the presence of sharp interference in the single photon regime, while reliably maintaining the information about the particular pinhole through which each individual photon had passed. This experiment poses interesting questions on the validity of Complementarity in cases where measurements techniques that avoid Heisenberg’s (...) uncertainty principle and quantum entanglement are employed. We further argue that the application of classical concepts of waves and particles as embodied in Complementarity leads to a logical inconsistency in the interpretation of this experiment. (shrink)

This paper reconstructs the history of the introduction and use of iterative algorithms in conservation biology in the 1980s and early 1990s in order to prioritize areas for protection as nature reserves. The importance of these algorithms was that they led to greater economy in spatial extent (“efficiency”) in the selection of areas to represent biological features adequately (that is, to a specified level) compared to older methods of scoring and ranking areas using criteria such as biotic “richness” (the number (...) of features of interest). The development of these algorithms was critical to producing a research program for conservation biology that was distinct from ecology and eventually led to what came to be called systematic conservation planning. Very similar algorithmic approaches were introduced independently in the 1980–1990 period in Australia, South Africa, and (arguably) the United Kingdom. The key rules in these algorithms were the use of rarity and what came to be called complementarity (the number of new or under-represented features in an area relative to those that had already been selected). Because these algorithms were heuristic, they were not guaranteed to produce optimal (most “efficient”) solutions. However, complementarity came to be seen as a principle rather than a rule in an algorithm and its use was also advocated for the former reason. Optimal solutions could be produced by reformulating the reserve selection problem in a mathematical programming formalism and using exact algorithms developed in that context. A dispute over the relevance of full optimality arose and was never resolved. Moreover, exact algorithms could not easily incorporate criteria determining the spatial configuration of networks of selected areas, in contrast to heuristic algorithms. Meanwhile metaheuristic algorithms emerged in the 1990s and came to be seen as a credible more effective alternative to the heuristic algorithms. Ultimately what was important about these developments was that the reserve selection problem came to be viewed a complex optimal decision problem under uncertainty, resource, and other constraints. It was a type of problem that had no antecedent in traditional ecology. (shrink)

In this study we present some contributions of the logician and philosopher Petre Botezatu (27.02.1911-01.12.1981), who turned the idea of complementarity,formulated by Niels Bohr for the interpretation of the wave-particle structure of the quantum world, into an ordering principle of his work. Thus, he understood general logic as a synthesis in which the style of classical logic is complementary to the style of the 20th century logic. He didn’t give up either the mathematical modelling of logical language or (...) the conceptual description through natural language. Thus, natural operational logic was created. Then Petre Botezatu assessed the achievements and failures of deduction in order to build the notion of methodological antinomy, and formulated five antinomies of axiomatization and five antinomies of formalization. The main purpose of this study is to present and interpret them. (shrink)

The noetic model is the first theory of any kind to explain qualia in physical terms. The formal delineation of the life principle or élan vital explains not only the origin of self-organisation in living systems, providing the basis for the first comprehensive dualist theory, but also is what makes the model empirically testable allowing this volume to make history. The floodgates are about to open to almost unimaginable advances in the field of consciousness studies. This book introduces a (...) comprehensive empirically testable model of dualism-interactionism to legitimise the interactionist model at a level tantamount to any other avenue of epistemological investigation. (shrink)

A modified version of Young's experiment by Shahriar Afshar demonstrates that, prior to a ``which-way'' measurement indicating which slit a particle goes through, an interference pattern exists. It has been claimed that this result constitutes a violation of the Principle of Complementarity. This paper discusses the implications of this experiment and considers how Cramer's Transactional Interpretation accomodates the result. It is shown that the Afshar experiment is isomorphic in key respects to a a spin one-half particle prepared as (...) ``spin up along x'' and post-selected in a specific state of spin along z. It is concluded that Bohr would have had no more problem accounting for the Afshar result than he would in accounting for the aforementioned pre- and post-selection spin experiment, in which the particle's preparation state is confirmed by a nondestructive measurement prior to post-selection. (shrink)

In part-1, I shall outline the principle details of Bohr’s interpretation. Bohr’s basic interpretive insight is ‘ quantum inseparability’ . Complementarity of phenomena and a “revision to our attitude towards physical explanation” then follow. Together , these can be said to constitute Bohr’s general viewpoint of ‘complementarity’. Bohr does not quite clearly spell out the content of these three ideas; I do.

A modified version of Young's experiment by Shahriar Afshar demonstrates that, prior to what appears to be a ``which-way'' measurement, an interference pattern exists. Afshar has claimed that this result constitutes a violation of the Principle of Complementarity. This paper discusses the implications of this experiment and considers how Cramer's Transactional Interpretation easily accomodates the result. It is also shown that the Afshar experiment is isomorphic in key respects to a spin one-half particle prepared as ``spin up along (...) x'' and post-selected in a specific state of spin along z. The terminology ``which way'' or ``which-slit'' is critiqued; it is argued that this usage by both Afshar and his critics is misleading and has contributed to confusion surrounding the interpretation of the experiment. Nevertheless, it is concluded that Bohr would have had no more problem accounting for the Afshar result than he would in accounting for the aforementioned pre- and post-selection spin experiment, in which the particle's preparation state is confirmed by a nondestructive measurement prior to post-selection. In addition, some new inferences about the interpretation of delayed choice experiments are drawn from the analysis. (shrink)

To what extent does the black hole information paradox lead to violations of quantum mechanics? I explain how black hole complementarity provides a framework to articulate how quantum characterizations of black holes can remain consistent despite the information paradox. I point out that there are two ways to cash out the notion of consistency in play here: an operational notion and a descriptive notion. These two ways of thinking about consistency lead to (at least) two principles of black hole (...) complementarity: an operational principle and a descriptive principle. Our background philosophy of science regarding realism/instrumentalism might initially lead us to prefer one principle over the other. However, the recent physics literature, which applies tools from quantum information theory and quantum computational complexity theory to various thought experiments involving quantum systems in or around black holes, implies that the operational principle is successful where the descriptive principle is not. This then lets us see that for operationalists the black hole information paradox might no longer be pressing. (shrink)

This article argues that a manuscript dated to the summer of 1927 by the editors of Bohr’s Collected Works was written a year earlier. The re-dating allows the conclusion that Bohr was well on his way to complementarity before his famous fight with Heisenberg over the uncertainty principle early in 1927. The literature that assumes that complementarity was Bohr’s response to Heisenberg is therefore in error. The editors of the Collected Works assigned the document the date of (...) 1927 because it refers to electron-diffraction experiments by Davisson and Germer, which were published in 1927. But as the article points out, Bohr and other leading physicists such as Max Born met Davisson in Britain in 1926 and discussed the experiments with him then. That demolished the basis of the earlier dating. Finally, the article argues that when the document takes its place between the Bohr–Kramers–Slater theory (1924) and the 1927 drafts of complementarity, everything falls neatly into place. (shrink)

A modified version of Young's experiment by Shahriar Afshar demonstrates that, prior to what appears to be a ``which-way'' measurement, an interference pattern exists. Afshar has claimed that this result constitutes a violation of the Principle of Complementarity. This paper discusses the implications of this experiment and considers how Cramer's Transactional Interpretation easily accomodates the result. It is also shown that the Afshar experiment is isomorphic in key respects to a spin one-half particle prepared as ``spin up along (...) x'' and post-selected in a specific state of spin along z. The terminology ``which way'' or ``which-slit'' is critiqued; it is argued that this usage by both Afshar and his critics is misleading and has contributed to confusion surrounding the interpretation of the experiment. Nevertheless, it is concluded that Bohr would have had no more problem accounting for the Afshar result than he would in accounting for the aforementioned pre- and post-selection spin experiment, in which the particle's preparation state is confirmed by a nondestructive measurement prior to post-selection. In addition, some new inferences about the interpretation of delayed choice experiments are drawn from the analysis. (shrink)

Niels Bohr’s complementarity principle is a tenuous synthesis of seemingly discrepant theoretical approaches based on a comprehensive analysis of relevant experimental results. Yet the role of complementarity, and the experimentalist-minded approach behind it, were not confined to a provisional best-available synthesis of well-established experimental results alone. They were also pivotal in discovering and explaining the phenomenon of quantum tunneling in its various forms. The core principles of Bohr’s method and the ensuing complementarity account of quantum phenomena (...) remain highly relevant guidelines in the current controversial debate and in experimental work on quantum tunneling times. (shrink)

Some contemporary theorists such as Mazzocchi, Theise and Kafatos are convinced that the reformed complementarity may redefine how we might exploit the complexity theory in 21st-century life sciences research. However, the motives behind the profound re-invention of “biological complementarity” need to be substantiated with concrete shreds of evidence about this principle’s applicability in real-life science experimentation, which we found missing in the literature. This paper discusses such pieces of evidence by confronting Bohr’s complementarity and ion channel (...) modeling practice. We examine whether and to what extent this principle might assist in developing ion channel models incorporating both deterministic and stochastic solutions. According to the “mutual exclusiveness of experimental setups” version of Bohr’s complementarity, this principle is needed when two mutually exclusive perspectives or approaches are right, necessary in a particular context, and are not contradictory as they arise in mutually exclusive conditions (mutually exclusive experimental or modeling setups). A detailed examination of the modeling practice reveals that both solutions are often used simultaneously in a single ion channel model, suggesting that the opposite conceptual frameworks can coexist in the same modeling setup. We concluded that Bohr’s complementarity might find applications in these complex modeling setups but only through its realistic phenomenological interpretation that allows applying different modes of description regardless of the nature of the underlying ion channel opening process. Also, we propose the combined use of complementarity and Complex thinking in building the multifaceted ion channel models. Overall, this paper’s results support the efforts to establish a more general form of complementarity to meet today’s complexity theory-inspired life sciences modeling demands. (shrink)

In the XXth century, the development of science has posed new challenges to the physicists. Waves have exhibited a corpuscular behavior while particles have exhibited undulatory behavior, but never simultaneously. This difficulty led Bohr to adopt the principle of complementarity, the figure by which the contradiction between wave and corpuscle is fixed. Thus the opposition between wave and corpuscle is absolutized. I think it was the non-consideration of dialectics that prevented Bohr from advancing towards the resolution of that (...) objective contradiction, that was about to be reflected on the theory.Consequently, it is the objective reality, in its unity and as a contradictory totality, that is removed from the theory. The scientific theory gives up the search for the internal connection of phenomena and its task becomes the mere ordination of such phenomena.The repression of the internal contradiction of reality has a second consequence in Bohr’s thought: objectivity becomes internal to language and it is considered under the figure of intersubjectivity. In fact, Bohr, by puting the correlation between object and measuring instrument as the instance in which knowledge is founded, is denying the possibility that there is a content of human representations that does not depend on the subject, i.e. is denying the possibility of objectivity.These are the general guidelines on which I will argue. (shrink)

In this essay, I want to argue that the existence of gender most times translated as gender binary, is a biological fact. What is at stake is a framework for transcending unequal gender binary to gender complementarity. Here, I propose to use Chimakonam’s Ezumezu logic as a mechanism for disclosing gender complementarity. The illogical, irrational and subjective perspectives on lopsided gender differences between men and women will be challenged in this essay. I will analyze the thrust of Ezumezu (...) logic, its major principles, structures, and pillars of thought. I will also demonstrate its global and contextual relevance. I will submit that Ezumezu logic can ground gender complementarity across global cultures. I argue that regardless of the physical differences between males and females, it is illogical to exploit such differences to promote gender stereotype. Keywords: Gender equality, Ezumezu Logic, Gender Complementarity, Jonathan Chimakonam. (shrink)

The article deals with the problem of the convergence between social and humanities knowledge and synergetics as a set of methodological principles. N.S. Rozov’s Theoretical History as a Scientific Research Program is taken as a separate field of social and humanities knowledge. It is proposed to consider the correlation of methodological principles of synergetics and theoretical and methodological provisions of Theoretical History by means of the methodological Principle of Complementarity. The heuristics of this correlation and possible forms of (...) its implementation are exemplified by the study of separatism. (shrink)

Like science, engineering engages in analysis and synthesis. But whereas scientists tend to break matter down to its most basic building blocks, engineers ultimately aim to assemble myriad components into a complex system. Because the components are heterogeneous, engineers must integrate knowledge in many areas, and multidisciplinary teamwork is common practice. Like science, engineering covers both the general and the particular. But whereas scientists tend to design particular experiments for discovering general laws of nature, engineers tend to formulate general principles (...) for designing particular artifacts. Modern engineering has developed general theories about large types of artificial systems, notably information, control, and computation theories. These engineering theories are most effective for designing concrete artifacts, yet their abstract theorem-proof format is closer to pure mathematics than the format of physical theories, which are closer to applied mathematics. The apparent paradox accentuates the engineering emphasis on creating things rather than discovering phenomena already existent. (shrink)

The article provides a reply to critical remarks made during the discussion about creativity and scientific knowledge. The authors propose to consider their concept of creativity not as antagonistic or incommensurable with the alternative, but rather co-existing through the complementarity principle. Responding to a comment about the socio-cultural conditionality of a particular cognitive situation, the authors question whether globalization seriously influence this matter in science. They support the statement about the importance of the interaction between science and art, (...) science and philosophy as an opportunity to consider scientific problems from the outside, in an unusual way. Regarding the comment about serendipity, the authors note that in certain cases we need exactly epistemological randomization, since we cannot consciously induce serendipity. In conclusion, thanks are expressed to all participants in the discussion. (shrink)