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Intrinsic Properties of Light and Corpuscles from Distant Sources

Zwicky, F. (1937) Intrinsic Properties of Light and Corpuscles from Distant Sources. Proceedings of the National Academy of Sciences of the United States of America, 23 (2). pp. 106-110. ISSN 0027-8424.

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Spectra of distant nebulae, compared with those of neighboring nebulae, are shifted toward the red by amounts which increase with the distance which the light has traveled. This fact indicates that we are confronted with a phenomenon which involves history on a large scale, history either of the universe as a whole, or history of some of its individual parts. Scientifically speaking, history means the change in time of dimensionless ratios of significant physical quantities. Thus, on the relativistic interpretation of the redshift of light from nebulae the dimensionless ratio D/d between two lengths changes (increases) in time. Appropriate choices for these two lengths are Bohr's characteristic length d = h^2/4π^2me^2 as a supposedly fixed terrestrial measuring stick, and D = V^1/3 where V is the volume which on the average contains one extragalactic nebula. However, many other interpretations of the redshift are possible. The assumption that history must be operative clearly suggests the necessity of an investigation of all dimensionless ratios between significant physical quantities. Only after this investigation has been completed will a final understanding of the redshift and other cosmic phenomena be possible. The following discussion will be concerned with the behavior of the most trivial dimensionless ratios only. A more general program may be outlined, but so far essential data for its realization are lacking.

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Additional Information:Copyright © 1937 by the National Academy of Sciences Communicated December 31, 1936 The program submitted in this paper was outlined several years ago and was discussed on various occasions with those astronomers at the Mt. Wilson Observatory who have made the investigation of distant nebulae their specialty. I am particularly indebted to Drs. W. Baade, E. Hubble and M. L. Humason for coöperating in the attempt to test some of the points of this program.
Issue or Number:2
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:5682
Deposited By: Archive Administrator
Deposited On:27 Oct 2006
Last Modified:02 Oct 2019 23:25

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