The limitations of science / by J. W. N. Sullivan.

  • Sullivan, J. W. N. (John William Navin), 1886-1937.
Date:
[1938]
Catalogue details

Licence: In copyright

Credit: The limitations of science / by J. W. N. Sullivan. Source: Wellcome Collection.

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    light years. But the state of equilibrium was unstable. The universe had an inherent tendency to expand which was only approximately counteracted by the gravitational at¬ traction of the matter in the universe. Once the expansion began, however slowly, it was bound to go on, for as the matter of the universe became more scattered its gravita¬ tional attraction became less effective. The radius of space to-day, Professor Eddington estimates, is not less than ten times its original radius. And the actual rate of expansion is itself continually increasing. It is probable that the radius of space is already increasing faster than the velocity of light, and this rate of expansion will grow greater. Already it would be impossible for a ray of light to go all round the world, for the circumference of the world is growing faster than light could overtake it. In the original state of equilibrium light travelled round and round the world until it was absorbed. Then the universe began to expand, and there came a period when the rate of expansion made it impossible for light to complete its journey. At this period ‘the bubble burst.’ It has been suggested that some of the nebulae we see in the heavens are seen from the back, by light which has travelled all round the universe. If this is so, then we are seeing these nebulae by light which started on its journey before the rate of expansion of the universe reached the critical value—before the bubble burst, in fact. This theory was introduced into science by the mathe¬ maticians, but there is good observational evidence for it. The vast majority of the nebulae whose motions have been measured are moving away from us with very great speeds. And these speeds are greater the farther the nebulae are from us, which is just what we should expect on the mathematical theory. The spiral nebulae, whose rate of scattering enables us to determine the rate of expansion of the universe, are the