Has the big bang theory been proven

what i mean is, do we know for sure that the big bang occurred? Is there definite, concrete evidence that it occurred, or is it just what it is named- a theory?

Scientists believe that the Big Bang really happened, so it is no longer a theory. Now if people would only acknowledge that God caused it, the world will be a happier place.

There is plenty of evidence that the Big Bang really did happen, the Cosmic Microwave Background Radiation and the accelerating red shifts and higher z numbers of galaxies the further away they are from us. When a theory has enough confiming evidence for long enough, a theory becomes a scientific law. Even after more than 151 years and lots of evidence confirming it, the theory of evolution is STILL a theory.

http://en.wikipedia.org/wiki/Redshift

Yes, it has.

The big bang is the process of expansion and is still visibly in progress. Since the universe is seen to be expanding today, theoretical cosmologists can make detailed predictions of the universe's denser and hotter past. The results of Big Bang predictions have been found to conform accurately and precisely to a variety of astronomical observations.
(From science, the origin of the universe is unknown. The big bang may or may not be related to the origin of the components of the universe.)
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There are no other theories that fit what data we know nearly as well.

The "Cosmic Background Radiation" is a really good piece of evidence that is best explained by the big bang. Another is the red-shift expansion of the universe (which needs a big bang to get it started, and dark energy to keep it going).

No one has seen it actually occurring, but the Cosmic Background Radiation seems to be the electromagnetic radiation, actually light, x-rays, gamma rays very red-shifted as the universe has expanded, that was emitted during the first very short period after the big bang.