许多世纪以来，自然哲学家们面临两种相互矛盾的理论：一种认为光是一种波，

For many centuries, natural philosophers faced with two conflicting theories: one believe that light is a wave, and another that light is made of particles stream composed. In 1900, Max Planck energy of quantum of light has determined that this is the prototype of duality theory of light. It means that light can sometimes behave as particles behavior, sometimes showing a wave of behavior. Then light having a photoelectric effect was confirmed particle properties. The Compton effect has proved photon particles of another nature, that momentum. In this experiment, the photon collision of the electrons, photons and electrons moving in two different directions and angles. We can use conservation of energy and momentum conservation laws to calculate the angle and energy of both movements. But the scattering of photons scattering billiards and there is a very interesting difference. Photon will not slow down, it is always the speed of light. Because with it the loss of energy and momentum, and its frequency is reduced correspondingly increasing wavelength, so that the speed remains unchanged.

For centuries, natural philosophers have faced two contradictory theories: one that holds that light is a wave and the other that light is made up of a stream of particles. In 1900, Max Planck proposed that light has a definite quantum energy, which is the prototype of the duality theory of light. It means that light can sometimes bemanifested as particle behavior, and sometimes it can bethedof the behavior of waves. The photoelectric effect then confirms the particle properties of light. The Compton effect proves that photons have another nature of particles, momentum. In this experiment, photons collide with electrons, and then photons and electrons move in two directions at different angles. We can calculate the angle and energy of the two motion seusing by means of the law of energy conservation and momentum conservation. But there is an interesting difference between the scattering of photons and the scattering of billiards. Photons do not decelerate, they always move at the speed of light. Because as its energy and momentum lose, its frequency decreases and its wavelength increases accordingly, its speed remains the same.

For many centuries, natural philosophers have faced two contradictory theories: one is that light is a wave, the other is that light is composed of particle flow. In 1900, Max Planck proposed that light has a certain quantized energy, which is the rudiment of the theory of duality of light. It means that light sometimes behaves as a particle, sometimes as a wave. Then the photoelectric effect confirmed that the light has particle properties. The Compton effect proves that photons have another property of particles, namely momentum. In this experiment, photons collide with electrons, and then photons and electrons move in two directions with different angles. We can use the law of conservation of energy and conservation of momentum to calculate the angle and energy of the two motions. But there is an interesting difference between photon scattering and billiard ball scattering. Photons do not slow down, they always move at the speed of light. Because with the loss of its energy and momentum, its frequency decreases and its wave length phase should increase, so its speed remains unchanged.<br>