Playing with Light

The eye is the jewel of the body

                          H.D. Thoreau

Over the years several theories have been formulated to explain the light and its behavior. It is quite amusing that our current understanding is a remarkable synthesis of previous and apparently contradictory theories.

The corpuscular theory, developed by Newton, is based on the assumption that light consists of extremely small particles, emitted by luminous bodies, subject to laws of mechanics. The wave theory, due to Huygens, explains the phenomena of light interpreting it as a wave object: light, according to Huygens, is a wave that propagates in space, or better, in a hypothetical medium identified as '"ether". The electromagnetic theory, formulated by Maxwell, says that the light is an electromagnetic wave: visible light and its beautiful colors are part of the electromagnetic spectrum. Quantum theory, due to Planck and Einstein, assumed that the emission and the absorption of light takes place by means of "wave packets" with well-defined energy and momentum, called light quanta or photons.

However, our main concern here is not about physics, rather about the pleasure of playing with light, thanks to photography, which literally means “writing with light”.