[john in missouri]

The brane theory is testable, but the equipment is very expensive and not yet available.

How might the brane theory be tested? When would such equipment be available?

The theologically interesting thing of all this, of course, is that it seems to form a plausible many-worlds scenario -- since presumably there would be a relatively infinite variety (perhaps within certain bounds) in the kinds of physical universes that could be produced by colliding branes. Thus, if verified experimentally, it could produce evidence that the universe could have originated without requiring it to be created by an intelligent creator(s). So it joins the Everett version of quantum mechanics in the limited range of plausible many-worlds theories.

[RightWhale]

Steinhardt included a testing mechanism in his theory. It has to do with measuring gravitational blue-shift. With new techniques of data mining being used, such as cointegration, computational subtraction, crystallographic analysis, meta-analysis, it could be just a matter of time until someone gets the right combination. Or perhaps the right data doesn't exist yet and can't exist until we have an interstellar interferometric baseline.