Note 14 — Chapter IV · THE THEORY OF QUANTA
Reading edition
This, however, is probably a temporary state of affairs. Certain Pasons for quantum transitions are already known. See J. Franck and P. Jordan, Anregung von Quaniensprüngen durch Stösse, Berlin, 1926; also P. Jordan, Kausalität und Statistik in der modernen Physik, Naturwissenschaften, Feb. 4, 1927.