In 1965 Arno A. Penzias and Robert W. Wilson of Bell Laboratories worked at a new horn antenna designed for detecting low levels of microwave radiation. They had a problem, they found a low microwave background “noise”, nothing different from the electrical noise which produce “snow” on your television screen. They tried all they could to eliminate it, they pointed the antenna to different points to see whether there was a directional dependency, then to different areas of the sky to check whether the “noise” came from up there, and got the same kind of noise, frustrating in the highly sensitive antenna they were testing and inventing. What a bummer.
Being persuaded that the noise was in their instrument, they took other, more sophisticated steps to eliminate the problem, such as cooling their detector to extremely low temperatures. The noise was still there, like a stubborn pest.
They found no explanations for the origin of the noise, in the end they concluded that it was indeed coming from space, but there was a problem: it was the same from all directions. They had found a distribution of microwave radiation which matched a blackbody curve for a radiator at about 2.7 Kelvins.
After all their efforts to eliminate the “noise”, they found that a group at Princeton had predicted with their studies the existence of a residual microwave background radiation left over from the Big Bang. Scientists were planning to conceive an experiment to try to detect the “noise”.
It is so that Penzias and Wilson were awarded the Nobel Prize in 1978 for the discovery of their “noise”.
This uniform radiation in the microwave region is observed in all directions in the sky. It shows the wavelength dependence of a “blackbody” radiator at about 3 Kelvins temperature. Scientists considered it to be the remnant of the radiation emitted at the time the expanding universe became transparent at about 3000 K temperature: the “Fiat Lux” moment.
The recent experimental discovery of the 3K microwave background radiation is crucial to the calculation of the standard “Big Bang” model of cosmology, and provides an estimates of relative populations of particles and photons. The most precise measurement of the temperature is 2.725 +/- 0.002 Kelvin.
Previous experiments had shown some anisotropy (non uniformity and directional dependency) of the background radiation due to the motion of the solar system, but data show also fluctuations. These fluctuations are necessary in Big Bang cosmology to give enough non-uniformity for galaxies to form. In contrast, the apparent uniformity of the radiation was at the basis for the “galaxy formation problem” after the Big Bang cosmology. In a sense, if everything is uniform, how comes the soup coalesced?
We have now a much higher resolution picture of the anisotropies in the cosmic background radiation. The data show a round figure of 109 photons per nuclear particle and this allows for the conditions of the “Fiat Lux” moment, when galaxies and stars formed. The Universe had to cool down until its temperature dropped below 3000K. Atoms formed and removed the opacity of the expanding universe soup; light got out and relieved the radiation pressure. Star and galaxy formation started when the gravitational attraction overcame the outward radiation pressure.
With atom formation and a transparent universe, the gravitational clumping began, and our Universe heard the words: “Fiat Lux”.
Massimo Marino has a scientific background: He spent years at CERN and The Lawrence Berkeley Lab followed by lead positions with Apple, Inc. and the World Economic Forum. He is also co-founder of “Squares on Blue”, a Big Data Analytics service company.
Massimo currently lives in France and crosses the border with Switzerland multiple times daily, although he is no smuggler.
As a Scientist, he envisions Science Fiction and went from smashing particles at accelerators at SLAC and CERN to smashing words on a computer screen.
He’s the author of multi-awarded Daimones Trilogy.
• 2013 Hall of Fame – Best in Science Fiction, Quality Reads UK Book Club