Reply #34: That's an excellent question

[derby378]

Have you heard of the concept known as M-theory? In a way, M-theorists have proposed some fascinating ideas for what our space is expanding "into" - if it is proper to speak of "a space beyond space."

A very simplified way of explaining one of these ideas in M-theory is that there are various multi-dimensional realities known as "branes" that coexist with each other. Each brane is potentially larger than our universe, and they are separated from each other by some indeterminate boundary. Every once in a while, however, two branes can "touch," or interact with each other.

The theory is that the Big Bang, as we perceive it, is actually the point at which two of these branes collided with each other, forming a new entity with at least three spatial dimensions and one time dimension that started expanding with an energy and life all its own.

Resident astrophysicists, feel free to jump in any time and set me straight... :hi: