Two uncharged particles are placed in an empty universe one light year apart. In one year, they will feel each other's presence and begin attraction. We are ignoring the uncertainty principle in this scenario.
Does this attraction begin in exactly one year? Or instead, does each particle spew out gravity attraction particles in all directions at a rate which is not exactly continuous in all directions and which requires an element of chance to strike upon its destination?
Same question for the other elementary forces.