The expanding universe / by Sir Arthur Eddington.

  • Eddington, Arthur Stanley, Sir, 1882-1944.
Date:
1940
Catalogue details

Licence: In copyright

Credit: The expanding universe / by Sir Arthur Eddington. Source: Wellcome Collection.

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    CHAPTER I THE RECESSION OF THE GALAXIES Pricked out with less and greater lights, between the poles of the universe, the Milky Way so gleameth white as to set very sages questioning.—Dante, Paradiso. I The, first hint of an “ expanding universe ” is con¬ tained in a paper published up November 1917 by Prof. W. de Sitter. Einstein’s general theory of relativity had been published two years before, but it had not yet attained notoriety; it was not until the eclipse expedi¬ tions of 1919 obtained confirmation of its prediction of the bending of light that public interest was aroused. Meanwhile many investigators had been examining the various consequences of the new theory. Prominent among them was de Sitter who was interested especi¬ ally in the astronomical consequences. In the course of a highly technical discussion he found that the rela¬ tivity theory led to an expectation that the most remote celestial objects would be moving away from us, or at least that they would deceive the observer into thinking that they were moving away. De Sitter was perhaps a tipster rather than a prophet. He would not promise anything definitely; but he sug¬ gested that we ought to keep a look out for the reces¬ sion as a rather likely phenomenon. Theory was at the cross-roads, and desired guidance from observation as to which of two possible courses should be pursued. If astronomers were to find a general motion of reces¬ sion of the most distant objects visible, it would be a strong indication that the road rather fancied by de Sitter was the one to follow. If not, the inference