The centenary of quantum mechanics brings into focus the question of the accuracy of established terminology for describing the radical transformations that occurred. Critical analysis reveals that the term “quantum revolution” fosters a simplified perception of a single, pivotal turn in physics during the 1920s and 1930s and provides a superficial account of the actual changes over the past 100 years. This article critically re-examines the established term “quantum revolution” from the perspective of its conceptual limitations in describing the real changes of the last century. Arguments are presented for its partial replacement with the more flexible concept of “revolutionary transformations in quantum theory and its interpretations”, which emphasises the processual and multifaceted nature of these changes. The methodological foundation of this research is the distinction between two types of interpretations of quantum theory: “pragmatic” interpretations, which focus on connecting the formalism with experiment, and “explanatory” interpretations, which aim to form conceptions of quantum reality. The application of the concept of a quantum revolution is justified for the pragmatic interpretation, which was formed in 1925–1927 and later became established as the orthodox view, but not for interpretations of the explanatory type. Three initial strategies for preserving classical language in the description of quantum phenomena are identified: classical realism, quantum dualism, and instrumentalism. The analysis addresses persistent historiographical myths surrounding the Copenhagen interpretation – namely, that it is inherent in the postulates of quantum theory, and that it is inherently instrumentalist and subjectivist. A distinction is shown between the orthodox (pragmatic) and the Copenhagen (explanatory) interpretations. Particular attention is paid to the realistic turn in explanatory interpretations (1952–1958), largely associated with the later works of Heisenberg. It is concluded that the development of quantum theory is characterised not by a single revolution, but by a series of transformations of varying revolutionary intensity, many of which occurred in parallel and are still far from complete.
The centenary of quantum mechanics brings into focus the question of the accuracy of established terminology for describing the radical transformations that occurred. Critical analysis reveals that the term “quantum revolution” fosters a simplified perception of a single, pivotal turn in physics during the 1920s and 1930s and provides a superficial account of the actual changes over the past 100 years. This article critically re-examines the established term “quantum revolution” from the perspective of its conceptual limitations in describing the real changes of the last century. Arguments are presented for its partial replacement with the more flexible concept of “revolutionary transformations in quantum theory and its interpretations”, which emphasises the processual and multifaceted nature of these changes. The methodological foundation of this research is the distinction between two types of interpretations of quantum theory: “pragmatic” interpretations, which focus on connecting the formalism with experiment, and “explanatory” interpretations, which aim to form conceptions of quantum reality. The application of the concept of a quantum revolution is justified for the pragmatic interpretation, which was formed in 1925–1927 and later became established as the orthodox view, but not for interpretations of the explanatory type. Three initial strategies for preserving classical language in the description of quantum phenomena are identified: classical realism, quantum dualism, and instrumentalism. The analysis addresses persistent historiographical myths surrounding the Copenhagen interpretation – namely, that it is inherent in the postulates of quantum theory, and that it is inherently instrumentalist and subjectivist. A distinction is shown between the orthodox (pragmatic) and the Copenhagen (explanatory) interpretations. Particular attention is paid to the realistic turn in explanatory interpretations (1952–1958), largely associated with the later works of Heisenberg. It is concluded that the development of quantum theory is characterised not by a single revolution, but by a series of transformations of varying revolutionary intensity, many of which occurred in parallel and are still far from complete.
Quantum physics, emerging from the intellectual crisis of classical mechanics at the dawn of the twentieth century, has over the course of twelve decades established itself as the most foundationally disruptive, experimentally verified, and technologically generative scientific framework in the history of human inquiry. This article presents a synthetic, balanced account of quantum physics across three temporal dimensions — its historical origins and theoretical maturation, its present theoretical frontiers and technological applications, and its future prospects across computing, communication, sensing, and the search for a unified theory of physical reality. Drawing upon foundational primary literature, historiographical scholarship, experimental physics, and contemporary quantum technology research, the article traces the discipline's evolution from Planck's quantum hypothesis of 1900 through the quantum mechanical revolution of the 1920s, the development of quantum field theory and the Standard Model, and the emergence of a second quantum revolution deliberately harnessing entanglement and superposition as technological resources. The analysis identifies three domains of outstanding significance for quantum physics in the present century: the unresolved interpretational and foundational questions surrounding the measurement problem and the nature of quantum reality; the technological race toward fault-tolerant quantum computing and global quantum communication networks; and the deep theoretical challenge of reconciling quantum mechanics with general relativity in a unified framework capable of describing physical reality at all scales. The article concludes that quantum physics remains an unfinished revolution whose most consequential theoretical discoveries and technological applications may lie not behind but ahead of us, and that understanding its past, present, and future is essential for any serious engagement with the scientific and technological landscape of the twenty-first century.
The ideas in Heisenberg's paper on quantum mechanics in 1925 mark the beginning not only of a new phase in modern physics, but also of Heisenberg's own philosophical journey. This thesis examines that journey between 1925 and the late 1950s by situating Heisenberg's philosophy of quantum mechanics in the context of his encounters with his contemporaries as well as the context of various strands of thought in the German-speaking world at the time. Heisenberg's early philosophical critique of the 'classical' viewpoint between 1925 and 1927 bears the decisive influence of Einstein's theory of relativity, more specifically, the positivism he saw as underpinning Einstein's emancipation from Newtonian physics. The positivist influence on Heisenberg's early attitude to quantum mechanics is evident in three ways: (a) his invocation of an observability principle in 1925 to justify the renunciation of the concept of the electron orbit, (b) an instrumentalist conception of understanding, which characterised Heisenberg's response to Schrodinger's demand for classical visualisation in space and time in 1926-7, and (c) the introduction of an operational definition of concepts such as position and velocity in 1927, in an attempt to replace the concepts of classical physics. But after discussions with Bohr and Einstein in 1926-7, Heisenberg soon recognised what we might term his `empiricist' viewpoint was problematic. In 1927 Heisenberg's thought undergoes a shift away from the `empiricist' viewpoint that had underpinned his early philosophy of quantum mechanics. The nature and scope of this transformation, which forms the central theme in this thesis, has, up until now, been poorly understood and often completely neglected. Through his discussions with Bohr, Heisenberg came to the realisation that despite their limitations, classical concepts were conditions for the possibility of the description of all experience. This marked the abandonment of his earlier attempt to replace classical concepts with quantum concepts. The recognition of the primacy of classical language forms the point of departure for much of Heisenberg's later thought, which brought him into contact with the attempts in the German-speaking world in the 1920s to reconstruct Kantian epistemology. By the mid-1930s, Heisenberg advocated a 'pragmatic transformation' of Kantian philosophy, in which classical concepts were held to be a priori in the sense that they remained the conditions for the possibility of experience, but were no longer held to be necessary or universal in a strict Kantian sense. After 1940 Heisenberg saw the paradoxes of quantum mechanics under the aegis of what can be termed a 'transcendental conception of language', according to which language is not a mere tool, but actively shapes, gives form, and objectifies, our 'reality'. The limits of a classical 'description' in quantum mechanics therefore came to signify for Heisenberg, the limits of 'objective reality'. While Bohr exerted perhaps the most important philosophical influence on Heisenberg, their intellectual relationship was characterised by disagreement and misunderstanding. This is most strikingly displayed in their respective views on wave-particle duality and complementarily. While after 1927 Heisenberg accepted Bohr's basic insight that our knowledge of the quantum world is mediated through classical language, he did not share Rohr's interpretation of complementarity. While Heisenberg certainly used terms such as 'complementarity' and wave-particle duality' in his writings, a close reading reveals that these terms had very different meanings for the two physicists. This is particularly evident in the contrast between Heisenberg's notion of wave-particle equivalence and Bohr's idea of complementarity. In bringing to light these divergences between Bohr and Heisenberg, this thesis lends further weight to the view - already advocated by scholars such as John Hendry and Mara Beller - that the so-called Copenhagen interpretation of quantum mechanics should not be thought of as a unified philosophical position, but actually comprises a number of different strands.
The article is devoted to the analysis of the origins of the second quantum technological revolution associated with the transmission and processing of quantum information. The objective of the study is to describe how radical restructuring of the foundations of quantum physics in the first quarter of the XX century led to the creation of technological innovations in the early XXI century. The first part of the paper clarifies the notions of scientific innovations and revolutionary transformations in science, and characterizes the main differences between quantum mechanics and classical physics. The second part argues that the second quantum revolution was prepared in the process of experimental verification of different views on the reality of the objects of quantum theory and the ways of their cognition.
A hundred years ago, physics underwent one of its most dramatic transformations - a paradigm shift that fundamentally changed our understanding of nature. Over the course of several revolutionary months in 1925 and early 1926, quantum mechanics emerged as a new, foundational theory of the microscopic world. With the publication of key papers by Werner Heisenberg and Erwin Schrödinger, the theoretical framework was established that radically redefined our perception of physical reality. These works demonstrated that atoms and subatomic particles do not obey the laws of classical mechanics, but instead follow entirely new, quantum laws. Born in those intense months, quantum mechanics became one of the cornerstones of modern physics and a lasting source of inspiration in both theoretical and applied sciences. This paradigmatic shift opened new avenues of research and laid the groundwork for scientific discoveries that continue to shape our understanding of nature today. This paper is dedicated to those pivotal historical moments - the months in which science made one of its deepest leaps and most consequential strides in comprehending the world.
Quantum mechanics emerged in the first decades of the 20th century as a powerful mathematical framework for describing microscopic phenomena. While its predictive success in specific domains is widely acknowledged, its ontological foundations remain deeply problematic nearly a century after its formulation. This paper examines the historical development of quantum mechanics, focusing on the introduction of key concepts such as the collapse of the wave function and quantum entanglement. It argues that these notions did not arise as direct consequences of experimental findings, but were introduced as additional postulates to resolve internal inconsistencies within the theory. The analysis highlights the circular nature of experimental confirmation in quantum mechanics and demonstrates that even the most rigorous tests, including loophole-free Bell inequality experiments, primarily validate mathematical predictions rather than resolve fundamental ontological questions. Multiple alternative interpretations proposed over the decades have failed to achieve consensus, indicating persistent conceptual difficulties. The paper concludes that quantum mechanics, particularly in its standard interpretation, functions more as a speculative mathematical construction than as a coherent and ontologically consistent theory of physical reality. «Keywords:» quantum mechanics, wave function collapse, quantum entanglement, measurement problem, ontology, Copenhagen interpretation, Bell inequalities, alternative interpretations, philosophy of physics
The foundations and meaning of quantum theory became a central issue to Albert Einstein and Niels Bohr since the onset of their impassioned debate in the 1920s, enriched by the contributions of many other distinguished scientists and philosophers.The questions are not settled down at all, despite the great achievements of the theory, its impressive accordance with experiment and predictive power.The fundamental and technological applications range from cosmology to biology, with the development of invaluable instruments and the design of new materials.Is quantum mechanics a complete or an incomplete theory?Is there an objective reality independent of the observer or is the reality created by the measurements?Are hidden-variable theories justifiable?Is there a quantum theory founded in a local-causal and non-linear approach that formally contains the orthodox linear theory as a special case?Can such a formulation unify classical and quantum physics?Are Heisenberg's uncertainty relations valid in all cases?Here, the subject is addressed as an adaptation of our contribution to the Colloquium "Quantal aspects in Chemistry and Physics.