Expert: Jayendra Upadhye - 4/30/2008

Question
gud after noon,sir.
sir, i wat to know wat xactly is d big bank theory????
i know dis frm other guys. bt i wat to know from a genius like u.
hope u will anwser my ques.
thanks.

Answer
Hi,
Dear Anand,
You appear to be not serious at all!
your english is terrible and you are calling big bang as big bank!!

As an indian myself, i expected much more precision from you.

Also the answer is too long for such a question.

In simple terms the big bang theory says ...
1 - The universe started from a very small point.
2 - It started 15 to 18 billion years ago.
3 - It is expanding even now.
4 - It was very hot when it started
5 - it is very cold now. (270 degrees centigrade below zero approx).
7 - It may stop expanding and start collapsing if there is sufficient
   matter in the universe.
   (problem is there is not sufficient visible matter to do that.
    So people are looking for Cold Dark Matter).
8 - It was extremely isotropic (having same properties in all
   directions at the time of the bang)
9 - It inflated (expanded faster than light) in the initial moments
   of the bang.
10 - For some time after the bang it was too hot for matter to
    coexist separately from energy.
11 - After a time that separation happened and the separating
    radiation now appears as the Cosmic Microwave Background
    radiation (CMB). It corresponds to radio emission of gaseous
    hydrogen at approx. 3 deg kelvin.

Hope that suffices.

regards
Jayen