Why do we not see the light travelling from the sun at night until it is reflected by the moon? That is, light travelling away from us does not appear, unless it is reflected as off smoke or dusty air. Ok, to simplify the sphere of the sun, consider a circle and the rays coming off the circle. There is no empty space at the perimeter, though the rays must necessarily become further away from one another the further they travel from the source- yet they do not! This is a form of Zeno’s paradox, where an arrow must travel half the distance in x time, and so can never arrive at its target- yet the arrow does arrive! The fact, shown by experiment, disproves mathematics and logic, and sends us back to our deductions, where a premise must be in error. There is no empty space between points on the perimeter, and each point is traced back to its source, apparently on the surface of the sphere that is the sun. This is because our assumption about rays, lines and points is an abstraction. Light “waves” are themselves circular or spherical, expanding as they proceed from the source to fill up all the space equally, and one can tell this because the light becomes weaker the further it proceeds. And hence, in this way, light does not behave at all like a particle but like a wave, as from a stone dropped into a pool, only in three dimensions, as with sound waves.
I you like this musing, check out the third blog from the beginning in the archives, about seeing into the past, literally.