The Light from the Big-Bang

#008

As you all might know, the universe came into existence following the auspicious event, termed as the Big-Bang. Scientists hypothesize that this was the moment which landmarks the beginning of time itself.

When you look into the night sky, we see thousands of twinkling objects. Almost all of them belong to our galaxy, the Milky Way.

With some exceptions like the Andromeda galaxy. However, we fail to see, what our telescopes can see. They can see a little farther, but what they actually see happened millions of years ago as the light which we see now, for extremely distant objects like Quasars comes from millions of light years away. So we can always say that watching the sky like that is similar to watching our own past. So, in that gaze, you always expect to see the objects which were formed first, during the Big Bang.

What were the first objects..?

Scientifically the first "thing" formed was an extremely hot plasma of gluons and quarks. After some cooling however they formed electrons, and finally the first atoms of deuterium, tritium and hydrogen. The scattered non-uniform matter slowly accumulated into clouds of gases, the first stars and galaxies.

Our ancestral stars must have been very bright and must have released tremendous amount of energy. Those stars might have turned into black holes and would be billions of light years away. But, their light must be just reaching us now. So, why can't we see their "Light". Why cant we observe the lights of the stars formed after Big Bang? Why is it that we cannot see the "Light from the Big-Bang".



To understand this, we need to know about a few things. 

Doppler Effect and Microwave noise observed in Bell Labs

Let's have a real life experiment. Go to nearest city road possible. And stand in front of a fast approaching ambulance with sirens on. You observe that the pitch of the siren is higher than normal. (Well, you cannot make any conclusion if you keep standing in front of such vehicle for long.) When the ambulance is moving away, from you, it is observed that the pitch is less than the actual pitch of the siren. This effect was explained by Austrian physicist, Christian Doppler, and is thus named as Doppler effect. It is the change in frequency of a wave in relative motion to the observer. During an approach, each successive crest is formed at a position relatively closer to the observer as it would have been in normal case. Thus, the resulting frequency increases. The reverse occurs while the source is moving away. While dealing with electromagnetic waves, when their is a decrease in frequency, it is called Red-shift, and in case of increase in frequency, a Blue-shift. 

While being engaged in astronomy, a red-shift shows that the star or galaxy is moving away from us. In the 1920's, Edwin Hubble showed that almost all the galaxies are red shifted, and that everything in the universe was moving away from each other. In 1929, he published a paper explaining that galaxies that were farther were more red-shifted than those close to us. The rate at which an object is moving away from us is directly proportional to it's distance from us.

In the year 1965, two american physicists Arno Penzias and Robert Wilson working in Bell Labs found more noise in a very sensitive microwave detector than it was ought to. The noise came in from all directions equally whether it was day or night, or any season. If there was any source of the noise, this unwanted signal must have been partial to one direction, but it was equally distributed, as if released from very far sources keeping us at their center. In fact, the sources should be far enough to be inside the observable universe.

Around the same time,Bob Dicke and Jim Peebles at princeton university were discussing about microwaves. As mentioned earlier, the light from the farthest parts of universe, the early universe, would be just reaching us now. However, accounting the expansion of the universe, this glow must be so red-shifted that it would be in microwave frequency. 

The Light from the Big-Bang is around us all the time, it is just invisible to our eyes. I would call it, the essence of Singularity, the presence of the creator. Well, if the light was so much red shifted to become a microwave noise, the further signals from the much earlier universe, must come to us in radio wave in a few centuries. Or, may finally become, the orchestra, the last man on earth would hear...

Thanks for reading,

And of course,

Good Day.