How to get 'a cosmos' from nothing

Carl Sagan once said “If you want to make an apple pie from scratch, you must first create the universe”. Theoretical physicist Lawrence Krauss has explained how to do that.

Why is there something rather than nothing? Krauss said that question implies a search for purpose that really doesn’t mesh with scientific inquiry. “The ‘why’ question is never really a ‘why’ question … really, when we say ‘why,’ we mean ‘how,’” he told me.

OK, so how can you get a cosmos from nothing? Krauss traces a series of discoveries building up from Einstein’s general theory of relativity to the latest studies of dark energy, explaining how scientists have determined that empty space is seething with energy in the form of virtual particles. From the perspective of quantum physics, particles are popping into and out of existence all the time. The way Krauss and many other theorists see it, nothingness is so unstable that it has to give rise to something … in our case, the universe as we know it.

What’s more, Krauss and his colleagues are coming around to the view that there could be a countless succession of big bangs, creating many universes with different parameters and laws of physics. Some of the universes in this multiverse fizzle back into nothingness immediately, while others — such as ours — hang around long enough to spawn galaxies and stars, planets and life. Scientists haven’t yet figured out a way to test this hypothesis, but it would explain how we’re lucky enough to live in a long-lasting universe: We just happened to win the prize of existence in a cosmic lottery.

“Some people say, ‘Well, that’s just a cop-out,’” Krauss acknowledged. “But it’s actually less of a cop-out than God.”

What appears to be confusing is the idea that “particles are popping into and out of existence all the time”. Doesn’t this violate the conservation of mass and energy?

Nope, it does not. 

Relatively recent experiments in quantum electrodynamics, notably the casimir effect, have shown that the classical interpretation of the conservation of mass and energy are bogus. Quantum physics is the new frontier.