The blossoming of quantum mechanics in Italy. The roots, the context and the first spreading in Italian universities (1900-1947)

The widespread positivist approach of physics research in Italy at the turn of the XIX and XX centuries did not provide a fertile ground for the scientific debate on the atomic structure of matter, which instead raged beyond the Alps in those same years and which gave birth, during the 1920s, to the quantum revolution. Experimental investigations in spectroscopy and radioactivity were carried out with discrete success in the 1910s and early 1920s by Italian physicists such as Antonino Lo Surdo and Rita Brunetti in Florence, stimulating an empirical knowledge of early quantum theory and the acquisition of the related laboratory skills. However, the theoretical framework necessary for the reception and development of the postulates and formalisms of quantum mechanics started to be cultivated in Italy with a delay of a few decades compared to Central European countries. The diffusion of quantum studies - with their unprecedented drive toward an integration of experiment and theory - took hold in Italy beginning from the establishment of the first theoretical physics chairs (1926) at the Universities of Rome, Florence and Milan, whose origins are here described in detail. Furthermore, the present paper presents a systematic analysis of the appearance of the quantum mechanical concepts in Italian university courses between 1927 and 1947.