*bites*
Jack:
I'm going to be slightly rude. Can I apologise in advance?
Your 'scientific method' is a litle too naive for my liking.
The important steps are that to stand up a theory must make predictions of the universe that can be tested and checked by others. How you a arrive at a theory is not really important - some theories are created in a moment of inspiration, others after years of careful observation.
It doesn't require that you perform an experiment that repeats the big bang to theorise that it took place, only that you explain what observations you would expect to be able to make in a universe created by a big bang.
Friedmann used Einstein's general relativity to argue the universe must be expanding to avoid gravity condensing it into a point. Einstein thought this was a complete fallacy, and thought his cosmological constant (a property of space that causes it to repel - i.e. a sort of anti-gravity) was right. Then Hubble made observations that showed the universe was expanding...
...the natural extrapolation is that if the universe is expanding it must be smaller the further you go back in the past.
Many scientists have tried to come up with alternatives to the big bang - for example, some have postulated a fractal universe. None have had any success so far.
I recommend Joao Magueijo's Faster Than The Speed Of Light for anyone who wants to read up on some modern big-bang physics.
I'm not going to touch evolution again with a 60ft barge-pole
Addendum: give me a powerful enough telescope and I can look at parts of the universe as they were several billion years ago. Why experiment when you can observe the real thing?
[ March 12, 2003, 23:55: Message edited by: Wanderer ]