Thus we can get the correct answer for the probability of partial reflection by imagining (falsely) that all reflection comes from only the front and back surfaces. In this intuitively easy analysis, the 'front surface' and 'back surface' arrows are mathematical constructions that give us the right answer, whereas .... a more accurate representation of what is really going on: partial reflection is the scattering of light by electrons inside the glass.
Richard P. FeynmanIn a way, the Nobel Prize has been something of a pain in the neck, though there was at least one time that I got some fun out of it, Shortly after I won the Prize, Gweneth and I received an invitation from the Brazilian government to be the guests of honor at the Carnaval celebrations in Rio.
Richard P. FeynmanThere is enough energy in a single cubic meter of space to boil all the oceans in the world.
Richard P. Feynman