Serendipitous discoveries often propel man’s understanding of the world around him. It is curious that the universe has extraordinary and miraculous ways of revealing its secrets in the most unexpected ways, at the least expected times. Today, I shall narrate one such discovery..a discovery that ended one of the hottest debates in the scientific community, a debate that lasted for almost a century.
It was year 1964. Two young American astronomers, Robert Woodrow Wilson and Arno Allan Penzias were appointed as radio astronomers in the famous Bell Labs in Holmdel, New Jersey. The Labs had special, ultra-sensitive, ‘horn-shaped’ cryogenic microwave receivers intended to ‘listen’ to outer space. As soon as the pair took charge of the horn- reflectors, they found something unusual, to their utter dismay.
The horn-reflectors were giving more ‘noise’ than expected. Forget about the noise due to earth’s atmosphere, this noise was much different..much more feeble to be given off by the milky way. It was from the microwave region of the Electromagnetic spectrum. The noise must not have been from outer space, they concluded. Thus, they went searching for its terrestrial source..and seemingly found it .
An examination of the horn antennae revealed an interesting finding. There was a couple of pigeons living in it, and had happily made it their ‘comfort station’. The pigeon droppings , or the ‘white dielectric material’ as Penzias described, could very well interfere with the signals, and could cause a similar noise. Hence, the pair and their team of highly qualified, talented radio astronomers spent the following two weeks cleaning pigeon droppings. The birds were trapped and sent by company mail to miles away.
But the pigeons returned. So did the noise. Finally, the team decided to shoot the culprits.
Yet, the noise persisted for another year. Having ruled out any other possible interference, and desperate to figure out its source, Bob Wilson and Arno Penzias decided to contact Robert Dicke of Princeton University for help. As soon as he heard the details over the phone, Robert Dicke was convinced. What the team at Bell Labs discovered was not a mere troublesome ‘noise’. It was the relic, the ‘holy remnant’ of the birth of the universe – The Cosmic Microwave Background Radiation (CMBR), that the ‘big bang’ cosmologists had been anticipating. The whole sky had been glowing at about a temperature of 2.7 degrees above absolute zero, and this manifested as the feeble radio voice from ‘out there’. Yes, the noise was ‘the voice’, the first cry of the newborn universe.
Thus was the discovery that sounded the death-knell for the ‘steady state’ universe that never had a beginning. Thus was the discovery that legitimized the birth of this grand cosmos from a primeval singularity. Thus was the beginning of a new era of our cosmic understanding.
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