Gravitational waves have been detected from the very "first sliver of cosmic time," and are being hailed as the "signature of a universe being wrenched violently apart when it was roughly a trillionth of a trillionth of a trillionth of a second old." This is the "long sought proof" of the Theory of Inflation, or the Big Bang, and Dennis Overbye of the New York Times does a fine job of explaining it all (March 17, 2014). Take a look!
We have dozens of books on the big bang, great reading for a bit of background knowledge. You might like to start with The Big Bang: theory, assumptions and problems / Jason R. O'Connell and Alice L. Hale, editors. Nova Science Publishers, 2012.