The box you are talking about refers in the form to caustics which designates in optics and mathematics the envelope of light rays undergoing reflection or refraction on a surface or a curve. it is clearly visible above swimming pools in particular. In substance while touching the light it figuratively refers to a kind of ether. Aether, in physics, was a hypothesis that space was filled with an invisible, immaterial substance called "luminiferous aether". Before the 20th century, scientists believed that light, like sound, had a kissin' of an environment to propagate. They propagate through the air, where the expected light is thought to propagate through the ether. The only conceptual link is the central vertical part, it represents Feynman's double slit experiment which illustrates the wave and particle nature of light and subatomic particles. Everything does not necessarily have a link, it is above all a graphic composition although it is partly composed of scientific elements.