[Edit this paragraph] The dispute between the wave theory of light and the particle theory
In the study of physical optics, the nature of light and the color of light become the focus. Regarding the nature of light, Descartes put forward two hypotheses in refractive optics, one of the three appendices of his methodology. One hypothesis holds that light is a particle-like substance; Another hypothesis holds that light is a kind of pressure mediated by "ether". Although Descartes emphasized the influence and function of medium on light, his two hypotheses have laid the groundwork for the debate between particle theory and wave theory later. /kloc-in the middle of 0/7th century, physical optics developed further. 1655, grimma Di, a professor of mathematics at the University of Bologna, first discovered the phenomenon of light diffraction while observing the shadow of a small stick placed in a light beam. Based on this, he speculated that light may be a fluid similar to water waves. Grimma designed an experiment: let a beam of light pass through a small hole, and in a dark room, let this beam of light pass through the small hole and shine on a screen. He found that after the light passed through the small hole, the light and shadow obviously widened. Grimma did further experiments. He let a beam of light shine on the screen of the darkroom through two small holes, and then he got an image with light and dark stripes. He thinks this phenomenon is very similar to water waves, and concludes that light is a fluid that can move in waves, and the different colors of light are the result of different fluctuation frequencies. Grimma was the first person to put forward the concept of "diffraction of light" and the earliest advocate of the wave theory of light. 1663, British scientist Boyle proposed that the color of an object is not the nature of the object itself, but the effect of light shining on it. He recorded the colored stripes in soap bubbles and glass balls for the first time. This discovery coincides with grimma's statement and lays the foundation for later research. Soon after, the British physicist Hooke repeated Grimm's experiment and put forward the hypothesis that "light is the longitudinal wave of ether" by observing the color of soap bubble film. According to this assumption, Hooke also thinks that the color of light is determined by its frequency. However, in 1672, the great Newton talked about his optical dispersion experiment in his paper "New Theory of Light and Color": let the sunlight pass through a small hole and shine on the prism of a darkroom, and a chromatogram will be obtained on the opposite wall. He thinks that the recombination and decomposition of light are like particles of different colors mixed together and separated. In this paper, he expounded the color theory of light with particle theory. The first debate between wave theory and particle theory was ignited by the fuse of "the color of light". Since then, there has been a long and fierce debate between Hooke and Newton. 1On February 6th, 672, the jury of the Royal Society, chaired by Hooke and composed of Hooke and Boyle, basically held a negative attitude towards Newton's paper The New Theory of Light and Color. Newton did not completely deny the wave theory at first, nor was he a supporter of the particle theory. But after the argument, Newton refuted Hooke's wave theory in many papers. Because Newton and Hooke did not form a complete theory at this time, the debate between wave theory and particle theory did not fully unfold. But that's the scientific argument. Once they appear, we should get to the bottom of it. Huygens is a famous astronomer, physicist and mathematician in the Netherlands. He supports wave theory and inherits and perfects Hooke's viewpoint. Huygens made important contributions to astronomy, physics and technical science in his early years, and systematically studied geometric optics. 1666, huygens was invited to the Paris academy of sciences and began to study physical optics. As an academician, Huygens went to England and met Newton in Cambridge. They appreciated each other very much and exchanged views on the nature of light, but at this time Huygens' view was more inclined to wave theory, so he and Newton had differences. It is this difference that inspires Huygens' strong enthusiasm for physical optics. After returning to Paris, Huygens repeated Newton's optical experiment. He carefully studied Newton's optical experiment and Grimma's first experiment, and thought that there were many phenomena that could not be explained by particle theory. Therefore, he put forward a relatively complete wave theory. Huygens believes that light is a mechanical wave; Light wave is a kind of longitudinal wave that propagates through the material carrier, and the material carrier that propagates it is "ether"; Every point on the wave surface itself is the wave source that causes the vibration of the medium. According to this theory, Huygens proved the laws of light reflection and refraction, and also explained the phenomena of light diffraction and birefringence and the famous "Newton's Ring" experiment. If these theories are not easy to understand, Huygens quoted an example from life to refute the particle theory. If light is composed of particles, then in the process of light propagation, particles will inevitably collide, which will inevitably lead to the change of light propagation direction. But this is not the case. While Huygens actively promoted the wave theory, Newton's particle theory was gradually established. Newton revised and perfected his optical work Optics. Based on various experiments, in the book Optics, Newton put forward two reasons to refute Huygens: first, if light is a wave, it should be able to bypass obstacles like sound waves without generating shadows; Secondly, the birefringence of Iceland spar shows that light has different properties on different surfaces, and the wave theory can't explain the reason. On the other hand, Newton extended his view of matter particles to the whole nature and integrated it with his particle mechanics system, which found a strong backing for particle theory. In order not to argue with Hooke again, optics was officially released in the second year after Hooke's death (1704). But by this time Huygens and Hooke had died one after another, and Bo said that no one was fighting. Newton became an unparalleled generation of scientific masters at that time because of his great contribution to the scientific community. With the improvement of Newton's reputation, people worship his theory, repeat his experiments and firmly believe in the same conclusion as him. Throughout the eighteenth century, almost no one challenged particles, and few people made further research on the nature of light. /kloc-At the end of 0/8th century, under the influence of German natural philosophy, people's thoughts were gradually liberated. Thomas Young, a famous British physicist, began to doubt Newton's optical theory. According to some experimental facts, Yang wrote a paper "Experiments and Problems of Light and Harmony" at 1800. In this paper, the harmonic series is lighter, because both of them are strengthened or weakened after overlapping. He thinks that light is an elastic vibration propagating in the etheric flow, and points out that light propagates in the form of longitudinal waves. He also pointed out that different colors of light and different frequencies of sound are similar. 180 1 year, Yang's famous double-slit interference experiment was carried out. The black and white stripes on the white screen used in the experiment prove the interference phenomenon of light, thus proving that light is a wave. In the same year, Yang published a paper in the Journal of Philosophy of the Royal Society, explaining Newton's ring experiment and his own experiment respectively, and put forward the concept and law of light interference for the first time. In 1803, Yang wrote a paper "Experiment and Calculation of Physical Optics". He further explained the diffraction phenomenon of light according to the interference law of light, and thought that diffraction was formed by the interference of direct beam and reflected beam. But because he thinks that light is a kind of longitudinal wave, he has encountered many troubles in theory. His theory was sharply criticized by British politician Brougham, calling it illogical, absurd and worthless. Although Yang's theory and later refutation have not been paid enough attention to or even vilified, his theory has aroused the interest of Newton School in optical research. 1808, Laplace analyzed the birefringence of light with particle theory and refuted Young's wave theory. 1809, Marius discovered the polarization of light in the experiment. When further studying the polarization in simple refraction of light, he found that light is partially polarized when refracted. Huygens once suggested that light is a kind of longitudinal wave, and longitudinal wave cannot be polarized in this way. This discovery becomes favorable evidence against wave theory. 18 1 1 year, when Luest studied the polarization of light, he discovered the empirical law of polarized light. The discovery of polarization and polarization law of light made the wave theory at that time fall into a dilemma and made the research of physical optics develop towards particle theory. Faced with this situation, Yang made an in-depth study of optics. 18 17, he gave up Huygens' theory that light is longitudinal wave and put forward the hypothesis that light is transverse wave, which successfully explained the polarization of light. After absorbing some Newton's ideas, he established a new wave theory. Yang wrote his new ideas to Arago of Newton School. The Paris Academy of Sciences awarded the best paper on optical interference. Fresnel, a civil engineer, is also involved in the dispute between wave theory and particle theory. 18 15, Fresnel tried to revive Huygens' wave theory, but it had nothing to do with Yang's paper on diffraction at that time. In his own paper, he proposed that the interference of various waves makes the synthetic wave have significant intensity. In fact, his theory is just the opposite of Yang's. Later, arago told him Young's new theory that light is a kind of shear wave, and Fresnel started his research based on Young's theory. 18 19, Fresnel successfully completed the interference experiment of two plane mirrors to produce coherent light source, and proved the fluctuation theory of light again after Young's interference experiment. After studying with Fresnel for some time, arago turned to wave theory. At the end of 18 19, after Fresnel's qualitative experiment on the propagation direction of light, he and arago established the transverse propagation theory of light waves. 1882, the German astronomer Fraunhofer first studied the diffraction phenomenon of light with grating. After him, another German physicist, Schveld, successfully explained the diffraction phenomenon of light through grating according to the new light wave theory. At this point, the new wave theory has been firmly established. Particle theory began to turn to the bad side. With the establishment of the wave theory of light, people began to look for the carrier of light waves, and the ether theory became active again. Some famous scientists have become representatives of ether theory. However, people encountered many difficulties in the search for ether, so they put forward various hypotheses, and ether became one of the focuses in the 19th century. When Fresnel studied ether, he found that the medium of shear wave should be a solid, and if ether is a solid, how can it not interfere with the free operation of celestial bodies? Not long after, Poisson also found a problem: if the ether is solid, there must be longitudinal vibration in the transverse vibration of light, which contradicts the new light wave theory. In order to solve all kinds of problems, Cauchy put forward the third theory of ether in 1839, which holds that ether is a negative compressible medium. He tried to solve the difficulties posed by Poisson. In 1845, Stokes made an analogy with paraffin, asphalt and gum, trying to show that some substances are hard enough to spread lateral vibration and compress and expand-so they will not affect the motion of celestial bodies. 1887, British physicist Michelson and chemist Morey denied the existence of ether through the "ether drift" experiment. But since then, there are still many scientists who insist on the study of ether. Even after Faraday's electromagnetic theory of light and Maxwell's electromagnetic theory of light were put forward, many scientists devoted themselves to the study of ether. /kloc-In the middle and late 20th century, wave theory won a decisive victory in the debate between wave theory and particle theory of light. However, the difficulties people encounter when looking for optical carriers indicate the crisis that wave theory is facing. 1887, German scientist Hertz discovered the photoelectric effect, and the particle nature of light was once again proved! At the beginning of the twentieth century, Planck and Einstein put forward the quantum theory of light. 1905 In March, Einstein published a paper entitled "Speculative Views on the Generation and Transformation of Light" in the German Yearbook of Physics. He thinks that for the average value of time, light shows fluctuation; For the instantaneous value of time, light appears as particles. This is the first time in history to reveal the unity of micro-object fluctuation and particles, that is, wave-particle duality. This scientific theory has finally been widely accepted by academic circles. 192 1 year, Einstein won the nobel prize in physics for his achievement of "wave-particle duality of light". 192 1 year, Compton proved the particle nature of X-rays in experiments. 1927, Gemel and later george thomson proved that the electron beam has the property of wave. At the same time, people have also proved that helium atomic rays, hydrogen atomic rays and hydrogen molecular rays all have the nature of waves. In the face of new facts and theories, the debate between wave theory and particle theory of light ended with "light has wave-particle duality" The dispute between wave theory and particle theory of light began with the two-point hypothesis put forward by Descartes in the early17th century and ended with the wave-particle duality of light in the early 20th century, which lasted for more than 300 years. Many famous scientists, such as Newton, Huygens, Thomas Young and Fresnel, became the main debaters on both sides of this debate. It is their efforts that have unveiled the confusing veil of "the essence of light".