where M P l 3 + 1 + δ δ is the 3+1+ δ δ dimensional Planck mass. However, we are assuming that these extra dimensions are the same size as the normal 3+1 dimensions. Let us say that the extra dimensions are of size n ≪ than normal dimensions. If we let r ≪ n, then we get (2). However, if we let r ≫ n, then we get our usual Newton's law. However, when r ≫ n, the flux in the extra dimensions becomes a constant, because there is no extra room for gravitational flux to flow through. Thus the flux will be proportional to n δ δ because this is the flux in the extra dimensions. The formula is: