Л Г Антипенко, Alexander Belyakov, Годарев-Лозовский Максим Григорьевич, Kirill Kopeikin, Аркадий Исаакович Липкин, А. В. Никулов, Alexander Panov, Andrey Yu. Sevalnikov, Galina Sergievskaja, Alexandr Spaskov, Vladislav Terekhovich, Yuri Vladimirov
This publication represents the materials of the discussion that took place in a form of a “round table” during the conference “Quantum Mechanics and Philosophical Discourse” (April 14–15, 2016, RAS Institute of Philosophy, Moscow, Russia). This discussion gives information, how the outcome of quantum experiments can chance the notion of reality. Experimental checks of Bell's theorem, Legett inequality, Leggett–Garg inequality and experimental delayed choice confirm, that for quantum objects it is necessary to revise classical realism very seriously. Different approaches to interpretation of observed phenomena also discussed. Within a framework of approach of modal metaphysics is shown how to resolve traditional paradoxes of quantum theory in particular it is shown for the first time what the “secret of quantum theory”, formulated by Richard Feynman, is related to.
This publication represents the materials of the discussion that took place in a form of a “round table” during the conference “Quantum Mechanics and Philosophical Discourse” (April 14–15, 2016, RAS Institute of Philosophy, Moscow, Russia). This discussion gives information, how the outcome of quantum experiments can chance the notion of reality. Experimental checks of Bell's theorem, Legett inequality, Leggett–Garg inequality and experimental delayed choice confirm, that for quantum objects it is necessary to revise classical realism very seriously. Different approaches to interpretation of observed phenomena also discussed. Within a framework of approach of modal metaphysics is shown how to resolve traditional paradoxes of quantum theory in particular it is shown for the first time what the “secret of quantum theory”, formulated by Richard Feynman, is related to.
The present study is concerned with the problem of realism in quantum mechanics. Contrary to the prevailing view that quantum mechanics forces us to abandon the concept of realism and reality, the author attempts to substantiate another standpoint. Quantum objects indeed exist in a different way from classical bodies. Before the act of measurement begins, one cannot attribute any specific properties to the quantum object observed, as they only occur in the course observation. The concept of observation, however, should not be interpreted as the inclusion of subjective traits in the description of nature. Observation records processes in space and time and establishes the fact of transition from the potential to the reality. The potential is described by a wave function, which in its meaning does not fall in the habitual space and time, whereas the actual is described in terms of a reduction of the wave function, i.e. the transition from a range of possible states to the single one, the observed. Whatever has been observed, in contrast, already belongs to ordinary space and time and can be detected. What follows is that, in quantum mechanics, it is the notion of reality which needs to be reconsidered, not the realism as such rejected. A reconsideration of this sort is conducted here within the framework of a double-modus picture of reality including both potential and actual being, where the quantum level of existence is distinguished from the observed modi of being as described by means of classical concepts. Such a scheme can be described in terms of Aristotelian metaphysics (the fact first pointed out by Heisenberg). The act of transition from potential to actual can be accounted for both in the language of Aristotle’s metaphysics and the language of modern science. In traditional metaphysics it is called the 'principle of individuation', while in modern science it is known as the extended Mach principle. It is argued that the development of these ideas leads to the rejection of Cartesian paradigm in which the existence of a material object always means an existence in space and time.
ABSTRACT The paper aims to bridge the history of quantum theory with its philosophical implications. The focus is not only on the scientific underpinnings of quantum mechanics (these theories emerged as ‘ad hoc’ responses to experimental anomalies) but also on the philosophical ramifications of its probabilistic nature and indeterminacy, which differ from classical realism. The paper examines Dirac's, Bell's, and modern views, focusing on how quantum mechanics (QM) challenges traditional notions of causality, objectivity, and truth while embracing epistemological and metaphysical perspectives. Debates over collapse theories and hidden variables are discussed, as well as Putnam's philosophical outlook, which includes his trenchant involvement with realism, logic, and the measurement problem. Finally, the paper proposes that QM represents a philosophical revolution that renews our understanding of reality, knowledge, and scientific explanation, rather than simply serving as a physical theory for assessing the prospects of quantum philosophy by connecting it to broader aspects such as relativity, causality, and scientific realism.
The framework of a simple opposition realism – anti-realism is not enough to analyze the views on the reality of unobservable objects of quantum theory. First, it is necessary to distinguish between realism in relation to the theory and realism in relation to the theory’s objects. Secondly, realism in relation to classical objects can be combined, both with realism and with anti-realism in relation to quantum objects. Third, the concept of “existence” and “to exist objectively” can have different meanings. To take into account these factors, the article describes three approaches: classical realism, quantum anti-realism, and quantum realism. I show that the debate around quantum reality has intensified in recent decades due to a series of new quantum experiments. The current stage of the debate is caused by the second quantum revolution relating to the transfer and processing of quantum information. Classical realism and old versions of quantum anti-realism have become insufficiently effective to explain the results of a series of experiments. Proponents of quantum realism, in turn, refer to the possibility of using the wave function to manipulate quantum objects before their measurement. In conclusion, I assume that not only theoretical discussions but also experiments and new technologies can have a major impact on the seemingly purely philosophical debate about reality.
Quantum mechanics marks a radical departure from the classical understanding of Nature, fostering an inherent randomness which forbids a deterministic description; yet the most fundamental departure arises from something different. As shown by Bell [1] and Kochen-Specker [2], quantum mechanics portrays a picture of the world in which reality loses its objectivity and is in fact created by observation. Quantum mechanics predicts phenomena which cannot be explained by any theory with objective realism, although our everyday experience supports the hypothesis that macroscopic objects, despite being made of quantum particles, exist independently of the act of observation; in this paper we identify this behavior as classical. Here we show that this seemingly obvious classical behavior of the macroscopic world cannot be experimentally tested and belongs to the realm of ontology similar to the dispute on the interpretations of quantum mechanics [3,4]. For small systems such as a single photon [5] or a pair [6], it has been experimentally proven that a classical description cannot be sustained. Recently, there have also been experiments that claim to have demonstrated quantum behavior of relatively large objects such as interference of fullerenes [7], the violation of Leggett-Garg inequality in Josephson junction [8], and interference between two condensed clouds of atoms [9], which suggest that there is no limit to the size of the system on which the quantum-versus-classical question can be tested. These behaviors, however, are not sufficient to refute classical description in the sense of objective reality. Our findings show that once we reach the regime where an Avogadro number of particles is present, the quantum-versus-classical question cannot be answered experimentally.
The problem of reality discussed in the present paper is evoked by debate on philosophical foundations of quantum mechanics. The author underlined the phase of discussions which may be called post-Einsteinian and post-Bohrian. Much consideration is given to problem of non-locality in quantum world, to famous Bell’s inequalities and Aspect’s experiments, which played an important role in proving superiority of Copenhagen interpretation for quantum theory, which is opposed to theories requiring the use of hidden parameters. It is shown that phenomena of quantum entanglement and non-locality gradually blur the classical concept of reality. Still the problem turns out to be much more complicated, because numerous studies question the rigid distinction between spirit and matter, and in this case the largest share is given to the creative ability of consciousness. It is stated that modal, possibilistic thinking approach opposed to anti-realism gains yet more significance and gives rise to “superrealism” requiring realization into actuality for everything thought of as possible. As the result, the famous philosophical proposition by René Descartes takes the following form: “I exist, ergo I am thinking the possible”. (“To exist means to think the possible”).
The article examines the controversial relation of scientific realism with quantum mechanics. To this end, two distinct discussions are invoked: the discussion about ‘realism’ in the context of quantum mechanics and the discussion about ‘scientific realism’ in the context of the general philosophy of science. The aim is to distinguish them in order, first, to argue that the former—revolving around ‘local realism’ and the theorems of Bell and Kochen–Specker—unjustifiably identifies realism with features of a particular worldview, and thereby fosters the impression that the failure of ‘local realism’ in quantum experiments constitutes a failure of scientific realism too; and, second, in light of the latter discussion, to claim that scientific realism and quantum mechanics can be compatible—there is ground for dealing with quantum measurement simply as a physical mind-independent interaction. Therefore, a realist approach to the theory is possible despite its notorious measurement problem, even if the issue of its interpretation is still disputed.