Ligth: Wave or particle?

In the late 1600s, English physicist, sir Isaac Newton, reasoned that because light travels in straight lines and casts sharp shadows, it must behave like a tiny stream of particles. Other scientists disagreed. They argued that light traveled in waves. because it bends slightly around objects and two light beams can pass through one another. This could only happen if light traveled in waves.

The controversy ended when it was demonstrated that light displayed an interference pattern. Since only waves exhibit interference patterns, light must be waves. A hundred years later, Albert Einstein challenged this theory after studying the behavior of light striking metal objects. Einstein stated that light was tiny energy packages, or photons.

Is light composed of waves or particles? Scientists have concluded that light has the properties of both waves and particles. When it travels, light acts like a wave. When it is given off or absorbed by objects, light acts like a particle.