Updated: Nov 21, 2021
Many elements of the universe whirl around us whose presence we neither see nor feel. Radio waves or Wi-Fi signals are good examples. One other source of great significance is the Cosmic Microwave Background Radiation. The CMBR is the brightest object in the universe responsible for more than 99% of all photons — the particles of light. As the wavelength of this radiation occurs in the electromagnetic microwave range it remains invisible to the human eye.
It was discovered in 1964 by Arno Penzias and Robert Wilson as a mysterious yet persistent hum in the data they were collecting (they were honored for their discovery with the Nobel Prize in 1978). Our question is “what is it?”
When the universe was born, it was very different from what it is today. Too hot and turbulent for the formation of stable atoms, the entire universe consisted of plasma or high temperature and high energy radiation.
After about 300,000 years, the universe had sufficiently cooled for the emergence of the first atoms, helium and hydrogen. As this differentiation progressed, it turned the entire cosmos into a hot gas cloud and a residue of white-hot radiation, the CMBR. Today, 13.8 billion years later, we can look at the baby picture of the universe in “all-sky-maps,” produced by the Planck telescope.
These pictures reveal what the universe was like billions of years ago; also, that the embryonic universe was not perfectly uniform. This unevenness consisted of miniscule temperature and density differences, not more than one part per million. Yet as tiny as these differences were, they were the forerunners or “seeds” from which even the largest structures of the universe emerged, galaxies, galactic clusters, and solar systems like ours. Even we ourselves were once hidden in that first flaring forth of a yet to be finished creation of indescribable beauty and mysterious complexity.
If this post awakens your interest in the relation of science and Christian faith, you can purchase my book Cosmos and Revelation: Reimagining God's Creation in the Age of Science here.