The Electromagnetic Spectrum

Abstract

I here have been few areas in physics which have caused as much interest as the nature of light. One early idea about vision said that ‘seeing’ an object involved something leaving your eye and travelling to the object. What about light itself? What exactly is light? Isaac Newton thought that light consisted of a stream of particles. This ‘corpuscular’ theory was first proposed by Pythagoras, the ancient Greek. Alongside this was the alternative view of Christiaan Huygens that light was a continuous wave. Another idea was that the darkness at night-time was caused by a dark gas which descended on the Earth each evening and which, if breathed in, gave you a weary tired feeling!