21. What is the extent of the gravitational field?

            The hydrogen atom produces a gravitational field. The far-field produced by the "almost-balanced" flow of an electron orbiting a proton is the gravitational field. For each orbital diameter of distance traversed from the center of the atom the field is more nearly balanced. Finally, at the distance called the "radius of the observable universe" the flow is completely balanced. That distance then is the extent of the gravitational field.