The “Steady-State” Universe

The “Steady-State” Universe

But acceptance of this obvious conclusion was not forthcoming. It would require much more
evidence to convince the scientists that the universe had a beginning. Although the universal
expansion was accepted, cosmology was considered by most to be a non-testable area that was
borderline science, mostly metaphysics. Certainly no one could reproduce the events of the early
universe in the laboratory. Failing that, what evidences could be found to support any theory of
cosmology? Little did anyone realize just how much evidence would be discovered. Prior to
World War II, the observed universal expansion and the successful theory of general relativity
stood alone as the basis for a scientific view of cosmology. And these alone did not convince
everyone that the universe even had a beginning.
Following World War II, scientists began to turn back to basic science research again, since the
war effort had diverted the brightest minds to weapons research. Some astrophysicists sought to
construct cosmological models, which agreed with the observed expansion of the universe, but
did not have a beginning. The “Steady-State” cosmology of Fred Hoyle is the best-known one,
recognized largely because of its philosophical appeal to many scientists. To its credit, it also
made some clear predictions that allowed it to be tested experimentally. Its premise is that new
matter is continually being created as the universe expands so that voids are filled in with the
new matter, thereby eventually forming new galaxies. Thus the universe always looks the same,
even though it is expanding. It would later become clear that the “Steady-State” model failed to
agree with several basic observations. One simple prediction, that there should be many galaxies
with vastly older stars than those of our Milky Way galaxy, is clearly wrong. All nearby
galaxies appear comparable in age to the Milky Way. However, as we look far out into the
distant regions of the universe we see evidence for much younger galaxies. This is exactly what
is expected in a universe in which nearly all the galaxies formed at the same time, since looking
at distant galaxies is effectively looking backwards in time due to the travel time of light. But
there are no hints of any galaxies much older than our own, as is expected from the Steady-State
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model. However, scientists remained reluctant to accept that the universe had a definite
beginning. That would require much more convincing evidence.