1911. 1st Edition. FIRST EDITION, PRESENTATION COPY, OF BOHR’S DOCTORAL THESIS. “Fra Forfatteren,” “From the Author,” appears in Bohr’s hand on the upper right corner of the front wrap. Bohr’s dissertation includes the first appearance of what is now known as the Bohr-van Leeuwen theorem stating that, in short, quantum physics is required to explain magnetic events. In other words, in a classical system, there is no thermal equilibrium magnetization – meaning, then, that classical physics cannot account for diamagnetism, paramagnetism, and ferromagnetism. This conclusion “was to prove determinative for the further development of modern physics” (van Vleck, JH, 1992). While the theorem was Bohr’s and appeared in his dissertation offered here, eight years after its publication, Hendrika Johanna van Leeuwen rediscovered it when doing her doctoral thesis – hence the theorem’s name.
“Bohr's doctoral dissertation was a purely theoretical work that… exhibited a mastery of the vast subject he had chosen, the electron theory of metals. This theory, which pictures the metallic state as a gas of electrons moving more or less freely in the potential created by the positively charged atoms disposed in a regular lattice, accounted qualitatively for the most varied properties of metals; but it ran into many difficulties as soon as a quantitative treatment was attempted on the basis of then accepted principles of classical electrodynamics” (Dictionary of Scientific Biography II, pp. 239). Bohr, however, recognized this. While he “made no use of the quantum hypothesis in his dissertation,” he clearly stated: "It does not seem possible, at the present stage of the development of the electron theory, to explain the magnetic properties of bodies from this theory" – a conclusion reflective of his evolving perception of classical physics” (Murdoch, Niels Bohr's Philosophy of Physics, p.4; Pais, Niels Bohr's Times, p. 111).
“In order to shed light on the nature of these difficulties, Bohr developed general methods allowing him to derive the main features of the phenomena from the fundamental assumptions in a very direct way. He could thus clearly exhibit the fundamental nature of the failures of the theory, which were in fact attributed to an insufficiency of the classical principles themselves. Thus, he showed that the magnetic properties of the metals could in no way be derived from a consistent application of these principles. The rigor of his analysis gave him, at this early stage, the firm conviction of the necessity of a radical departure from classical electrodynamics for the description of atomic phenomena” (DSB).
"Bohr’s doctor's thesis had pushed him to the outer frontier of classical physics…It could just be that [it was] this experience that “encouraged him to push into areas beyond, into the mysteries of quantum physics, as he was soon to do” (Pais). Bohr’s work on his 1911 doctoral thesis would lead, eleven years later, to the Nobel Prize. His research led him to encounter Planck's early quantum theory describing energy as tiny particles, or quanta. By 1912, Bohr was working with Thompson, exploring Rutherford’s discovery of the nucleus and development of an atomic model, and studying the properties of atoms himself. Gradually, Bohr combined Rutherford’s description of the nucleus and Planck's theory about quanta. He then used them to elucidate what happens inside an atom and from there, developed a model of atomic structure. Eleven years after publication of his thesis, Bohr was awarded the Nobel Prize "for his services in the investigation of the structure of atoms and of the radiation emanating from them." Item #1412
CONDITION: Copenhagen, Thaning & Appel, 1911. Royal 8vo. , 120 pp. Original printed wrappers, firmly and solidly attached. Slight professional repair to the top inch of paper on the spine. No fading; clean and bright inside and out. Near fine condition.