Hidden dimensions may be all around us but they are too small for us to notice—for now. On paper the math behind string theory is making a strong case for these extra dimension. The next step is to find some experimental evidence to support the claims and predictions made by string theory.
The Large Hadron Collider is right now the best chance for testing these predictions about extra dimensions. What is also fascinating is when Brian Greene talks (5:45) about the possibility that the big bang was not the beginning or rather only the beginning for our little speck somewhere within a much larger universe where our big bang is one of many. Unfortunately he isn’t very optimistic about us ever being able to explore them but that is really getting ahead of ourselves.