In The Beginning

Source: TV Fanatic 

How everything started is a giant unknown, one of the real mysteries left in science for our generation or the next to try and solve. 

However there are a few things we do know.

We know the Universe had a beginning. 

This seems self-evident? Everything has to have a start, a creation? Well not necessarily.

Steady State Theory held the attention of many cosmologists through the 40s, 50s and 60s. Steady State was the idea that the Universe has always looked the way it does and always will. 

It had been known since the 1920s that the Universe was expanding. It was found from observations that all distant stars were moving away from us and the further away they were, the faster they appeared to be moving. 

This is easier to conceptualise if you picture a balloon covered in dots. 

Source: hk-physics

As you blow up the balloon all of the dots move away from each other. The further apart two dots were to begin with, the further they end up when your balloon is blown up.

That the Universe is expanding we would expect it to becoming less and less dense over time. There would be more and more space between things.

Steady state accounts for this expansion by postulating the existence of a field, which they named the C-field. This would create matter at a continuous rate to just balance everything out. The rate needed was tiny only one atom of hydrogen per the age of the Universe. So it wasn't an idea that was easy to rule out.

The clincher in the battle between Steady State Theory and The Big Bang Theory came down to one defining observation.

If The Big Bang Theory was correct, all of the stuff in the Universe must have formed some time after the beginning. For this to happen we know it would need a whole lot of heat. Similar to how stars form the heavier elements, something must have started all of this off and that something must have been hot.
In the Steady State Theory, everything just always existed. So if we could find evidence that the Universe was really hot one time in it's past that would rule out Steady State Theory. 

This evidence was found in the early 1960s by accident. Two physicists were looking at the sky looking for sources of radiation that might effect the data received from satellites. Everywhere they looked they found this faint unexplained radiation.  

After re-checking all of their equipment and even shooing away pigeons they resided that the source of this radiation was an unknown. 

Coincidentally, just down the road (in Princeton, New Jersey) a group of physics were calculating what they expected the residual heat left over from The Big Bang would look like now. 

The expected radiation matched the un-explained radiation found. 

This lead the The Big Bang Theory to become the leading theory in our descriptions of our Universe.  


- Sinead