ABSTRACT
The properties and nature of light intriguing the mankind since the beginning of human civilization. Today, passing more than 25 centuries from the first known philosophical treatment of the optical phenomena, which the early Greek philosopher Pythagoras have been made, the scientist are still astonished by the dual nature of light. Maxwell’s classical electromagnetic theory perfectly describes the propagation of light, whereas the quantum theory treats the interaction between light and matter or the absorption and emission of light. So, if someone ask “What is light?,” there is no a simple answer to this simple questions.
