‎"HEISENBERG, WERNER.‎
‎Zur Theorie der ""Schauer"" in der Höhenstrahlung (+) Zur Theorie der explosionsartigen Schauer in der kosmischen Strahlung. II. - [HEISENBERG'S ""EXPLOSION SHOWERS"" OF COSMIC RAYS]‎

‎Berling, Springer, 1936 & 1939. 8vo. In two contemporary halv cloth bindings. In ""Zeitschrift für Physik"", Bd. 101, 1936 & 113, 1939. Entire volumes offered. Stamp to front free end-paper and titlepage, otherwise fine and clean. Pp. 513-538"" Pp. 673-702. [Entire volume: VII, (1), 790 pp.].‎

Reference : 49169

‎First printing of Heisenberg's two famous papers on ""explosion showers"" of cosmic rays"" a subject he himself considered ""the frontier of a wholly new and revolutionary physics."" (DSB). ""It appears to me that Heisenberg's experiences with the Fermi theory made a deep and lasting impact on him, which changed the course of his thinking. The strong increase of cross sections with energy he had found led him to surmise that physics may have to be revised at short distances. Already in his 1936 paper [the present] we find references to 'the introduction of a universal length which perhaps must be connected with a new change a principle in the formalism, just as for example the introduction of the constant c led to a modification of prerelativistic physics"". Note also that 1936 was the last year Heisenberg worked on quantum electrodynamics."" (Pais, Inward Bound).""While engaged in this political fight, Heisenberg vigorously pursued his search for a consistent quantum field theory. His tenacious adherence to what he believed to be the beginning of a new quantum revolution is in part attributable to his concern for the vitality of German research. In 1935 Heisenberg's research began to focus on high-energy collisions of elementary particles in cosmic rays, the highest energy phenomena then known. Examining the Fermi (weak) interaction in early 1936, Heisenberg discovered a mathematical minimum length, about the size of elementary particles, that appeared to trigger the onset of ""explosion showers"" of cosmic rays. The minimum length, a notion that he had earlier considered in the context of quantum eletrodynamics, marked, he belived, the boundary of quantum mechanics and the frontier of a wholly new and revolutionary physics.Heisenberg's revolutionary notions were challenged soon afterward by the alternative quantum electrodynamics of ""cascade showers."" generated by Bremsstrahlung and pair production. A controversy ensued, mainly between Heisenberg and several American physicists, over the existence of explosion showers and over allegiances to the two types of theories and their implications for the future course of physics. Fermi's weak-field theory soon proved inapplicable to the problem, but in 1939 Heisenberg extended his notions to Yukawa's (strong) meson theory of nuclear forces, revitalizing the controversy into the war years. A universal minimum length remained a permanent feature of Heisenberg's physics. Although explosion showers later called ""multiple processes,"" were discovered after the war in cosmic-ray events, the invention of renormalization techniques and the experimental confirmation of quantum electrodynamics to the highest energies left Heisenberg's physics with only minority support."" (DSB)Cassidy 1936b, 1939a.‎