The debate on how the universe came to be rages on. Perhaps, however, we are a little closer to understanding why there is “something”, including us, rather than “nothing”.

[div class=attrib]From Scientific American:[end-div]

Why is there something rather than nothing? This is one of those profound questions that is easy to ask but difficult to answer. For millennia humans simply said, “God did it”: a creator existed before the universe and brought it into existence out of nothing. But this just begs the question of what created God—and if God does not need a creator, logic dictates that neither does the universe. Science deals with natural (not supernatural) causes and, as such, has several ways of exploring where the “something” came from.

Multiple universes. There are many multiverse hypotheses predicted from mathematics and physics that show how our universe may have been born from another universe. For example, our universe may be just one of many bubble universes with varying laws of nature. Those universes with laws similar to ours will produce stars, some of which collapse into black holes and singularities that give birth to new universes—in a manner similar to the singularity that physicists believe gave rise to the big bang.

M-theory. In his and Leonard Mlodinow’s 2010 book, The Grand Design, Stephen Hawking embraces “M-theory” (an extension of string theory that includes 11 dimensions) as “the only candidate for a complete theory of the universe. If it is finite—and this has yet to be proved—it will be a model of a universe that creates itself.”

Quantum foam creation. The “nothing” of the vacuum of space actually consists of subatomic spacetime turbulence at extremely small distances measurable at the Planck scale—the length at which the structure of spacetime is dominated by quantum gravity. At this scale, the Heisenberg uncertainty principle allows energy to briefly decay into particles and antiparticles, thereby producing “something” from “nothing.”

Nothing is unstable. In his new book, A Universe from Nothing, cosmologist Lawrence M. Krauss attempts to link quantum physics to Einstein’s general theory of relativity to explain the origin of a universe from nothing: “In quantum gravity, universes can, and indeed always will, spontaneously appear from nothing. Such universes need not be empty, but can have matter and radiation in them, as long as the total energy, including the negative energy associated with gravity [balancing the positive energy of matter], is zero.” Furthermore, “for the closed universes that might be created through such mechanisms to last for longer than infinitesimal times, something like inflation is necessary.” Observations show that the universe is in fact flat (there is just enough matter to slow its expansion but not to halt it), has zero total energy and underwent rapid inflation, or expansion, soon after the big bang, as described by inflationary cosmology. Krauss concludes: “Quantum gravity not only appears to allow universes to be created from noth ing—meaning … absence of space and time—it may require them. ‘Nothing’—in this case no space, no time, no anything!—is unstable.”

[div class=attrib]Read the entire article after the jump.[end-div]

[div class=attrib]Image: There’s Nothing Out There. Courtesy of Rolfe Kanefsky / Image Entertainment.[end-div]