Quote:
Steinhardt and Turok’s model is motivated by string theory, an approach to unify relativity and quantum mechanics in which there are extra dimensions of space beyond the three we can see. In their model, our visible universe is a 3D sheet called a membrane, or brane, floating in our four-dimensional space. Another 3D brane, with possibly very different physics, hovers nearby. The branes collide so often, making our heat up to an astronomical 10^23 Kelvin and expand, with some energy eventually condensing into matter. From our point of view, confined to our brane, it would look like a big bang- even though the universe was already there.
- New Scientist - 23 April 2007