WHY was the big bang so very big? It has been a struggle to explain why the infant universe expanded so rapidly. But now Stephen Hawking at the University of Cambridge, and colleagues, think they are close to perfecting an answer - by treating the early cosmos as a quantum object with a multitude of alternative universes that gradually blend into ours.

The idea that the universe expanded at a blistering rate in the first 10^-34 seconds after the big bang was proposed to explain why regions of the universe separated by vast distances have such a similar background temperature: before inflation occurred, these regions would have been close together with similar properties. But just why the universe inflated in the first place remains a mystery.

"There's no fundamental theory that can explain why inflation happened in our universe - it's just proposed as an ad hoc solution that explains ...  Read More...