Echoes from big bang causes white noise..?

Question

..the ever present noise in electronic systems.. what's this all about..? it was mentioned today to me when talking about Bell Labs and research work done there by a scientist long ago and i was wondering more about it (the echoes as white noise).

Answer 1

Its called cosmic microwave background radiation (CMB). It was discovered in 1965 by Arno Penzias and Robert Woodrow Wilson. They were working for Bell Telephone Laboratories near Holmdel Township, New Jersey.

CMB is a "black body" radio static, that comes from all directions in the sky. It's the same as if it was coming from something with a temperature of 2.725 kelvin (-454.765 degrees F). The frequency is spread all over, with a peak at about 160.4 GHz. That means you can't get it on you average radio.

CMB is not really an "echo" -- it's the original signal of the early universe. When the universe was about 380,000 years old, it had a temperature of about 3000 kelvins. Before that time, it was too full of gas for light to shine through it. But when it cooled down to 3000 K, the light could get through. That's exactly the same light we see today, but cooled down (and frequency shifted) because it's spread out so much.

Answer 2

After about 300,000 years of expansion, the universe became transparent to light. The cosmic background radiation is those same photons, very tired by now.

I did read somewhere that if you tune your tv in-between stations, a very small percentage of the 'snow' that you see is due to cosmic background radiation. I'll try to find a source and put the link here. It was not much - a lot less than 1%, from memory.

Hmm ok it was Bill Bryson. So I wouldn't take it as gospel.

Excerpt from 'A Short History of Everything'

"Incidentally, disturbance from cosmic background radiation is something we have all experienced. Tune your television to any channel it doesn't receive, and about 1 percent of the dancing static you see is accounted for by this ancient remnant of the Big Bang. The next time you complain that there is nothing on, remember that you can always watch the birth of the universe."

Answer 3

There is a thing called the cosmic microwave background which is the remnant radiation of the Big Bang. It is very low level - about 3 degrees Kelvin. It is pretty much omnidirectional (except for some lumps). It was discovered accidentally by a couple of guy using a sensitive horn aerial at Bell Labs - they could not get rid of this low level interference after they tried everything they could think of (including cleaning pigeon poo up). Eventually they decided they had picked up the residual radiation, the existence of which had been predicted theoretically.