Light behaves
as a particle
would behave
Light
behaves
as a wave
would behave
By 1703, Isaac Newton (1642-1727) was firmly established as the preeminent natural philosopher (scientist) in England because of his work in mechanics. It was in that year that Newton, now in his sixtieth year, wrote a new book entitled Optics in which he espouses his belief that the nature of light is a collection of particles called corpuscles. These particles, traveling at sufficiently high speed, could: 1) travel in straight lines; and 2) reflect off flat surfaces in ways consistent with the laws of reflection. Refraction could be explained if the speed of light increased as it traveled into a denser transparent medium.
Consider a corpuscular model as described by Prof. Rubin
In 1678, a Dutch scientist, Christiaan Huygens (1629-1695) suggested that light was a wave phenomenon. He believed that the phenomena exhibited by light at the time (rectilinear propagation, reflection, refraction) could be explained if light were a wave. He fashioned a model, known as Huygens’ Principle, which could explain how light could travel through space. Every point on a wave front can be considered a source-point for the next wave front. While Huygens ideas drew some interest in the eighteenth century, Newton’s corpuscles were generally accepted over Huygens’ wavelets.
Consider a wave model as described by Prof. Rubin.
See also Mr. Hwang's view of Huygens' principle
