|image by Fred Fokkelman via sxc,hu|
When people talk about the Big Bang Theory they often say things like, “Well what went bang?” or “You can’t get something out of nothing.”
To begin, nothing exploded.
The Big Bang was the point at which the universe expanded from a tiny region of super dense and hot energy. And at which point time as we know it began.
The term was coined by physicist William Hoyle as an insult. He favored the steady state theory, which held the universe always existed in its current state.
Since Hoyle’s day our understanding of universe has increased several folds, but we still don’t have all the answers. As to where the mass/energy came from there are a few competing theories.
Theoretical physicist Lawrence Krauss posits that the energy making up the quantum singularity popped into existence the same way virtual particles have been observed to spontaneously form and decay in the lab. For a more in depth explanation check out his book The Universe From Nothing. He also has a lecture of the same name on you tube.
The oscillating universe model posits that our universe is the current one in a long series of big bangs and big crunches(when the universe reaches it expansion limits and implodes).
There is also the theory that our universe is one of a countless number connected by membranes, (like soap bubbles). The energy/mass from one can be transferred to another via nexuses(points in space and time shared by universes)or black holes.
Modern steady state theory says the universe has always existed in some form. Be it purely energy, matter, or some combination of the two.
The take home here is that while scientists don’t have all the answers, they’re
working to find new and better explanations for why there’s something instead of nothing.