Operationalism as the philosophy of Soviet physics: The philosophical backgrounds of L. I. Mandelstam and his school (Q1595325)

This paper surveys \textit{L. I. Mandel'stam}'s contributions to the philosophy of physics, also considering their historical and philosophical background. Mandelstam (1879-1944), influential Soviet physicist, best known for his contributions to radio-physics, optics, and statistical physics, founder of the Mandelstam school in Moscow being still alive today, formulated the principles of his operationalism in lecture courses and seminars in the context of considerations on the nature of physical objects and the structure of physical theories. Examples are given from lectures on the Theory of Relativity and on Quantum Theory, published in his ``Complete Works'' [5 vols., Izd. AN SSSR, Moscow (1948-1950, vol. 4, 1955, Zbl 0065.17006)]. ``According to Mandelstam, any question about the reality of an object should be posed with respect to an apparatus or instrument by means of which the object in question is assigned a given physical value'' (p.\ 417). This is exemplified by two examples concerned with the reality of components resulting from the Fourier analysis of physical phenomena. In a further section Mandelstam's operationalism is compared with that of \textit{P. Bridgman} as presented in ``Logic of Modern Physics'' [Macmillan, New York (1927)], thereby showing its originality. The main influence on the emergence of Mandelstam's philosophical position is seen in his contacts to the Neo-positivist \textit{R. v. Mises} in Berlin and to his teacher and mentor \textit{F. Braun} in Strasbourg. Finally the method of expedient idealization is presented as an example for the further development of Mandelstam's operationalism in his scientific community.