Niels Bohr eBooks
eBooks di Niels Bohr di Formato Pdf
Niels Bohr (1885-1962) svolse le sue prime ricerche al Cavendish Laboratory di Cambridge. Nel 1913, in una comunicazione divenuta famosa, espose la sua «teoria dell'atomo», destinata a diventare la base di tutta l'odierna fisica atomica. Premio Nobel per la fisica nel 1922 e animatore della scuola di Copenaghen, nel 1943 dovette fuggire dalla Danimarca invasa dai nazisti. Negli Stati Uniti prese parte alle ricerche per la costruzione della bomba atomica, pur caldeggiando un controllo internazionale sugli armamenti nucleari.
On the Quantum Theory of Line-Spectra: On the Hydrogen Spectrum. E-book. Formato PDF Niels Bohr - Forgotten Books, 2017 -
In Part III the problem of the series spectra of other elements will be treated from a similar point of view. As pointed out by the writer in an earlier paper, a simple explanation of the pronounced analogy between these spectra and the hy drogen spectrum is offered by the fact, that the atomic systems, involved in the emission of the spectra under consideration, in a certain sense may be regarded as a perturbed hydrogen atom. On the other hand, a clue to the interpretation of the characteristic difference between the hydrogen spectrum and the spectra of other elements was first obtained by sommerfeld's theory of the stationary states of cen tral systems referred to above. As shown by sommerfeld, it is possible on this theory to account in general outlines for the well known laws governing the fre quencies of the series spectra of the elements; and, as it will be shown in Part III, it is also possible, on the basis of the formal relation between the quantum theory and the ordinary theory of radiation, in this way to obtain a simple interpretation of the laws governing the remarkable differences in the intensities with which the various series of lines appear, which on the combination principle would constitute the complete spectra under consideration. As regards the detailed discussion of these spectra, however, it is necessary to bear in mind that the part played by the inner electrons in the atoms of the elements in question forms a far more intricate pro blem than the perturbing effect of a fixed external field on the hydrogen atom. For the treatment of this problem the theory of conditionally periodic systems based on the conditions (22) does not seem to suffice, while, as it will be shown in Part III, it appears that the method of perturbations exposed in the following lends itself naturally also to this case.
The Theory of Spectra and Atomic Constitution: Three Essays. E-book. Formato PDF Niels Bohr - Forgotten Books, 2017 -
The three essays which here appear in English all deal with the application of the quantum theory to problems of atomic structure, and refer to the different stages in the development of this theory.