Einstein said there is no usch thing as dark. Only absence of light. For example, there is no such thing as cold other than a linguistic characteristic we subjectively use to describe relatively less motion. He said that dark is the same thing. Dark is nothing more than a linguistic way of describing lesser light. Visible light is a portion of a wave. Yes? So even though we visibly see darkness, the wave is still there but only out of our range of visibility? Not so sure.