A detailed analysis of the five Einstein's contributions on the photons, the phonons, the Brownian motion, the interaction radiation-matter, and the statistics of undistinguishable particles shows that even without special and general relativity, Einstein's ideas have already brought a revolution in our conception of nature
Annali dell'Istituto e Museo di storia della scienza di Firenze A. 4, fasc. 2 (1979), p. 49-70