If the universe is expanding/stretching, what is it expanding/stretching into? Is it nothingness? Or rather is it is 'nothingness' only in the sense that we cannot give it a word or a definition? Where did all the mass-energy in the universe came from? Did it came from nothing? Of course, the last question is absurd. Since we define the universe as being everything( EX: energy-mass,all the temporal and spatial concepts), then it makes little sense to imagine something 'outside' the universe, or 'before' the big bang. To make such inquiry, to me, is merely a limitation on language itself. There in fact a deeper level of human consciousness or intuition; A feelings/sense/mind s-eye that give us the conviction that there is 'something' out there. Something that our langauge cannot take us.