“Unlike mathematicians, who are at liberty to play in the field of ideas, physics is bound to nature, and at least in principle, is allied with material things. Yet all this raises a liberating possibility, for if mathematics allows for more than three dimensions, and we think mathematics is useful for describing the world, how do we know that physical space is limited to three? Although Galileo, Newton and Kant had taken length, breadth and height to be axiomatic, might there not be more dimensions to our world?”