The Evidence Continues to Grow

The Evidence Continues to Grow

When I was recently asked, “What is the greatest scientific discovery of the 20th century?” I
didn’t need any time at all to reflect. Without hesitation I replied that the discovery of the
Cosmic Microwave Background Radiation, made in 1965, showed us clearly that the universe
had a beginning. One of the most fundamental questions of science was settled by one very clear
observation made by accident. Two Bell lab scientists, Robert Wilson and Arno Penzias, were
testing out a new microwave receiver, when they noted a low temperature background “noise”
that persisted despite all efforts to remove possible causes, including the radioactivity in pigeon
dung! Not knowing any plausible reasons for the microwave radiation, they began calling
scientists who might be able to help. When they relayed their findings to Jim Peebles, an
astrophysicist at Princeton University, they finally received their stunning answer. It turned out
to be the predicted radiation left over by the initial explosion that began the expansion of the
universe itself. The Bell lab microwave receiver was the first telescope capable of analyzing
such light waves, allowing an accidental discovery. This fascinating story is told in more detail
by Robert Jastrow’s book God and the Astronomers [12].
What was it about this discovery that convinced scientists that the universe had a very hot,
explosive beginning? Did this simply fit a growing paradigm that had already gained a foothold
in the scientific community? Hardly! As a mocking gesture, the name “Big Bang” had been
given to the theory that predicted such a hot, explosive beginning by astrophysicist Fred Hoyle,
who held firmly to his favored “Steady State” theory, in which the universe has no beginning. In
fact, a number of scientists had earlier considered the Big Bang model to be philosophically
undesirable, since it reveals a beginning which science itself cannot fully explain. Indeed, the
Big Bang theory demands a cause from beyond the universe itself, since all matter, space, and
even time were created in one spectacular event. As Jastrow writes,
At this moment it seems as though science will never be able to raise the curtain
on the mystery of creation. For the scientist who has lived by his faith in the
power of reason, the story ends like a bad dream. He has scaled the mountains of
ignorance; he is about to conquer the highest peak; as he pulls himself over the
final rock, he is greeted by a band of theologians who have been sitting there for
centuries [12].
No, the entire scientific community was not overwhelmingly eager to receive supporting
evidence for such a theory. For it demands answers from outside the realm of science. But by
1965, for most scientists the evidence was too glaringly obvious to ignore. It is noteworthy that
the scientific community chose to accept what the evidence was clearly revealing, in spite of
personal bias against it. Perhaps we can all learn something important from this. But at the start
of the 20th century, the view many scientists held concerning cosmology had no basis in
scientific evidence. Let us briefly review how these changes came about.