This article was found by Majorana’s brother among Ettore Majorana’s files and was published in 1942 after Majorana’s disappearance in the international Italian journal Scientia. It is a rather special article in several respects. It was intended to present the point of view of a physicist about the value of statistical laws in physics and social sciences to scholars of a broad spectrum of different disciplines such as sociology and economics. It also considers philosophical aspects related to the nature and value of deterministic and statistical laws in science. In his article, Majorana considers quantum mechanics as an irreducible statistical theory because the theory is not able to describe the time evolution of a single particle or atom in a controlled environment at a deterministic level. He concludes that quantum mechanics suggests that there is an “essential analogy between physics and the social sciences, between which an identity of value and method has turned out”. By analyzing the messages of this paper we conclude that Majorana deserves a great tribute not only for his exceptional achievements in theoretical physics but also for his fresh and original views on the importance and role of statistical laws in physics and in other disciplines such as the social sciences.
This article was found by Majorana’s brother among Ettore Majorana’s files and was published in 1942 after Majorana’s disappearance in the international Italian journal Scientia. It is a rather special article in several respects. It was intended to present the point of view of a physicist about the value of statistical laws in physics and social sciences to scholars of a broad spectrum of different disciplines such as sociology and economics. It also considers philosophical aspects related to the nature and value of deterministic and statistical laws in science. In his article, Majorana considers quantum mechanics as an irreducible statistical theory because the theory is not able to describe the time evolution of a single particle or atom in a controlled environment at a deterministic level. He concludes that quantum mechanics suggests that there is an “essential analogy between physics and the social sciences, between which an identity of value and method has turned out”. By analyzing the messages of this paper we conclude that Majorana deserves a great tribute not only for his exceptional achievements in theoretical physics but also for his fresh and original views on the importance and role of statistical laws in physics and in other disciplines such as the social sciences.
This article was found by Majorana's brother among Ettore Majorana's files and was published in 1942 after Majorana's disappearance in the international Italian journal Scientia.It is a rather special article in several respects.It was intended to present the point of view of a physicist about the value of statistical laws in physics and social sciences to scholars of a broad spectrum of different disciplines such as sociology and economics.It also considers philosophical aspects related to the nature and value of deterministic and statistical laws in science.In his article, Majorana considers quantum mechanics as an irreducible statistical theory because the theory is not able to describe the time evolution of a single particle or atom in a controlled environment at a deterministic level.He concludes that quantum mechanics suggests that there is an "essential analogy between physics and the social sciences, between which an identity of value and method has turned out".By analyzing the messages of this paper we conclude that Majorana deserves a great tribute not only for his exceptional achievements in theoretical physics but also for his fresh and original views on the importance and role of statistical laws in physics and in other disciplines such as the social sciences.
This year is the centenary of the birth of Ettore Majorana, one of the major Italian physicists of all times. In this note we briefly sketch a few biographical details about Ettore Majorana and introduce and discuss the main points of Majorana's 10th article. In his article Majorana explicitly considers quantum mechanics as an irreducible statistical theory because the theory is not able to describe the time evolution of a single particle or atom in a precise environment at a deterministic level. This lack of determinism at the level of an elementary physical system motivated him to suggest a formal analogy between statistical laws observed in physics and in the social sciences. We hope the occasion of the centenary of the birth of Ettore Majorana will be useful to remember and to reconsider not only his exceptional achievements in theoretical physics but also his fresh and original views on the role of statistical laws in physics and in other disciplines such as the social sciences.
The physicists working in several areas of research know quite well the name of Ettore Majorana, since it is currently associated to fundamental concepts like {\it Majorana neutrinos} in particle physics and cosmology or {\it Majorana fermions} in condensed matter physics. But, probably, very few is known about other substantial contributions of that ingenious scholar, and even less about his personal background. For non specialists, instead, the name of Ettore Majorana is usually intimately related to the fact that he disappeared rather mysteriously on March 26, 1938, just seventy years ago, and was never seen again. The life and the work of this Italian scientist is the object of the present review, which will also offer a summary of the main results achieved in recent times by the historical and scientific researches on his work.
My thesis investigates a debate between Vienna and Berlin about the view that the basic laws of nature are genuinely indeterministic that started long before the advent of quantum mechanics. It involved two different readings of Ludwig Boltzmann's legacy statistical mechanics and two different answers to how causality and ontology ought to be combined. Having adopted Ernst Mach's weak notion of causality, the local Viennese tradition could more easily contemplate ontologies for irreducibly statistical laws that were different from classical physics, while the Berlin tradition departed from Planck's reading of the Kantian tradition, according to which strictly deterministic laws represented an indispensable basis even for probabilistic theories.\nVienna Indeterminism, as I shall call the first reading, became characteristic for a series of physicist-philosophers connected to the Institute of Physics at the University of Vienna, among them Franz Serafin Exner, Erwin Schrödinger, Philipp Frank and Richard von Mises. It involved the acceptance of the highly improbable events admitted by the second law of thermodynamics, an assent to Mach's definition of causality in terms of functional dependencies, an empiricist shift of the burden of proof on the determinist's shoulders, and the adoption of the relative frequency interpretation of probability. Planck and his student Moritz Schlick initially rejected all of these creeds.\nWhile the Viennese reading of Boltzmann's legacy made it possible to accept probabilistic laws as genuine laws years before the advent of quantum mechanics, Schlick had to take a strictly verificationist tack to reconcile his views on probability with the failure of a Kant-inspired notion of causality enforced by the changes in physics. Until his death however, Schlick remained committed to the Spielraum interpretation of Johannes von Kries, compensating his qualified acceptance of indeterminism with an emphasis on the limits of language that were enforced by Heisenberg's uncertainty relations.\nIn view of claims that scientists' abandonment of determinism and causality was triggered, or at least enhanced, by external factors, among them the anti-scientific Weimar milieu and Bohr's power politics, the reconstruction of the philosophical debates between Vienna and Berlin requires historical contextualization. To this end, I initially recapitulate the Forman thesis and the discussions ensuing from it. Most important among them are the recent books of Cushing and Beller that, rejecting Forman's strong claims, nevertheless deny any constructive influence of the scientific aspirations of German physicists on the philosophical debates about causality and indeterminism in the 1920s.\nAgainst this picture, I argue that the philosophical aspirations of physicist-philosophers were rather genuine and followed influential role models, among them Helmholtz and Mach. They represent a characteristic trait of the German-speaking scientific world and were expressed in academic addresses and in the publication of popular writings. After 1913, this philosophical discourse was conducted, to an increasing extent, on the pages of Die Naturwissenschaften. In a separate chapter, I study the role of philosophical and cultural matters in this journal, which can hardly be separated from the personality of its founding editor Arnold Berliner. At about 1930, this discourse among physicist-philosophers partly merged into scientific philosophy, as conducted by Logical Empiricists, and the newly founded Erkenntnis.\nOne of the characteristic features of the discourse among physicist-philosophers was that they were not strictly indebted to philosophical schools but rather willing to form strategic alliances. Such alliances emphasized one philosophical aspect that was considered pivotal at the time which other features, often expressing severe disagreements of content, were played down. This process can be witnessed at the end of the discussion between the Viennese and the Berliners in the 1930s, at a time when Schlick had already become the center of the Vienna Circle. Being confronted with a plethora of "metaphysical" misinterpretations and having taken the linguistic turn, Frank and Schlick formed a strategic alliance on the 1936 Copenhagen Congress for the Unity of Science. It brought them into opposition with Schrödinger's quest for a modification of quantum mechanics, although Schrödinger continued to be a staunch advocate of indeterminism. This year thus signifies the end of the coherence of Vienna Indeterminism, a tradition that reaches back to the publication of Boltzmann's Lectures of Gas Theory.
Philosophical reflections on physics and its theories have been shaping the agenda of general philosophy of science, including issues such as the nature of scientific theories, the meaning of scientific terms, and scientific modeling. But physics is also well worth being considered a special science of its own, whose methods and tools raised specific questions for philosophers of science: this is the approach followed in this chapter, which has as its main thread the role of mathematics in physical theories. It tackles classical issues concerning measurement and determinism and long-standing controversies in the philosophy of statistical mechanics (how may the reversible laws of mechanics account for the irreversible principles of thermodynamics?) and in the philosophy of quantum physics (does quantum mechanics provide us a with a complete description of quantum phenomena?). It also addresses emerging issues in the field, such as computer simulations and their role between theory and observation.
Quantum mechanics based on the probabilistic approach provides a powerful tool for accurate prediction and interpretation of quantum phenomena, allowing statistically sound predictions about the behavior of microparticles and quantum systems. This statement emphasizes the probabilistic nature of quantum mechanics, its applicability to quantum phenomena and microparticles, as well as the statistical nature of its predictions when applied to the macro effects of classical physics. In addition, the role of statistics and probability in various fields of science, such as particle physics, thermodynamics, biology, sociology, psychology, economics and finance, is discussed. The philosophical implications of the probabilistic approach and the associated limitations and challenges are also considered.