In a blog post at the Foundational Questions Institute, William Orem is peeved by the idea that "nothingness" is an operable term when it comes to cosmological beginnings:
It’s at least worth noting that the word 'nothingness' itself containsa postulate that is by no means self-evident: namely, that '-ness' can meaningfully be attached to the term 'no-thing' in the way it might be attached to 'red' or 'happy.' When we agree to the attachment we are ceding the strange point that there is a state or condition of being in no state or condition, something very much like 'being not being.' Viewed this way, 'nothingness' appears to be a round square.
In a similar vein I would submit that the phrase 'emerged out of nothing' is grammatically sound but has no meaning, just as we can speak with perfect clarity but no content about a room full of married bachelors. The point is that the only quantum fluctuations with which we are familiar are embedded in spacetime, or are themselves expressions of spacetime, which we offhandedly refer to as 'nothingness' or 'emptiness' at our peril.
I'm certainly guilty of this, as astronomer Pamela Gay, a.k.a. "Star Stryder," has pointed out to me.
Thanks to some interesting new work that Orem points out, "what came before the Big Bang?" might someday be addressed. By clearing up a little semantic confusion, we are expanding not only what we know, but adding to what we know how to know.
I just picked up Brian Greene's Fabric of the Cosmos, which I'm enjoying immensely.