The Big Bounce theory says that before the Big Bang there were other Big Bangs over and over. For example, the universe would have a Big Bang within it and then this new mini-universe would expand, then start collapsing, and as it finishes collapsing, it would "bounce" back into a Big Bang, while the greater universe stays constant.
Since this is a big explosion, nothing resists it, so we can't find any trace of the other universe ours started in, but would we be able to find evidence for this in the small dimensions that exist in string theory? They're so small they would resist the Big Bang. If the LHC found these dimensions, would it confirm the theory?