Interpretation of gravity and others. Aids for explaining the phenomena of the universe. Take the mental image of Hawking's universe, I mean, surface of a sphere where latitude (vertical axis) is the time and longitude (horizontal axis) is the space. If we imagine that the sphere has a rotating movement (as Earth does), it is produced a centrifugal force that is perpendicular to the surface of the sphere (the universe) and therefore unperceptible for him. If we also collect the Einstein’s idea that mass curves space-time, we could visualize the universe as the surface of a sphere filled with "mountains" produced by the masses it contains. When the surface of the sphere is curved by the effect of a mass, it loses the perpendicularity with respect to the centrifugal force, and therefore this force starts to work on those objects near the surface curvature. This effect would be seen as gravity. This mental image might also be useful to show the rapid remoteness of distant galaxies (and therfore, very old) since it occurs in latitudes near the pole, where the rotation (gravity) has less effect. The mental image could also give an interpretation to the inflation of the universe in its primitive states if in that state is deducted the influence of gravity, very weak in regions near the pole. You can correct the mental model assuming a sphere flattened at the poles, if necessary. These images do not pretend that be real, they are just one way to explicate the phenomena observed. Thank you. Javier G.