Is it possible that our 3D universe is just a shadow in 3D space of 4D or higher dimensional reality? And we are limited in our perception of it by our 3-dimensionality. In other words like Flatlanders would just see s square of a cube sitting on the plane or passing through the plane. Actually they would see a line, but they could deduce that this line represents a square by the number and type of corners (angles) they could feel by going around the line? Similarly we deduce a lot of things by studying nature. But all of the results are limited by our 3-dimensionality?