I am very grateful to the President Kong and Dongrun Foundation to give me such an opportunity. I want to talk about the relationship between cognition and innovation about "Light". This topic is "Light".
As an important window of human’s perception in the world, people’s understanding of the nature to light is an endless and tortuous process. In fact, there were many ideas for quite a long time. What is the light on earth? As an important scientific knowledge, the French Scientist Pierre Gassendi and British Scientist Newton viewed that light is the grain of linear propagation. Therefore, we have the so-called Newtonian optics and geometrical optics. We view light as a particle, which has lasted for a very long time.
After 150 years, Thomas Young did an experiment and he made the light pass through a parallel double slits. If it is transmitted in straight lines, it would be impossible to pass as said by Newton. If the light is a wave, you can make out the stripes and you can see it. At this time, we can say that light is wave.Look forward in half a century, British Scientist Maxwell established a Maxwell equation, in which the transmission speed of electromagnetics and the speed of light measured at that time was basically the same, so that light is actually one of the electromagnetic waves.
However, a hundred years later, at the beginning of the last century, Phillip Lenard did an experiment called the photoelectric effect. The experiment tested the relationship between the light intensity andelectron energy. He found that the light intensity and electron energy were independent and not correlated. There was no relationship between the electronic energy and the intensity of light. There is no way to explain the characteristics of light wave, so that we have new understanding of light.
In 1905, Einstein published the famous Restricted Theory of Relativity, and he also published an article "Photoelectric Effect of Light" in the same year. Einstein pointed out that "light is actually a particle, with the attributes of particles". This work was very controversial among Einstein's work. This was 1913, eight years after the Photoelectric Effect of Light by Einstein. Planck (Who is generally considered as young Einstein's excavator and benefactor) worried that the Particle Theory of Light would affect the reputation of Einstein. Einstein may not be elected as the Academician of Prussian Academy of Sciences. He said: "In short, Einstein has made the outstanding achievements in almost all the important questions of modern physics, and he is forgivable in some occasional mistakes, such as the quantum theory of light. Even in the most rigorous subject, it is also risky to put forward a new concept." The final experiment proved that Einstein was right, and in fact we now know that there is the diphase of wave and particle in light. In fact, Einstein has improved our awareness of light to a higher level. In 1921, the Royal Swedish Academy of Sciences awarded Einstein a prize. He won this award by virtue of the principle of photoelectric effect, which is the basis of the quantum concept of light.
Similarly, after almost a decade, Einstein published the General Relativity in 1915. He also put forward the interpretation of the principles of the laser, and proposed such a so-called concept of stimulated radiation in 1917. The two cognitive corpuscular properties and quantum characteristics of light have laid the foundation for light stimulated radiation effect later.
Innovation is the source of cognition, which is very important. In science education, the basic science and fundamental research are very important. We know that the human beings have made great progress on the basis of photoelectric cognition of Einstein, which could do the innovation on cognition. We know that the quantum of light has changed the life of human beings, from the light communication. Today we are in the era of the network, if there is no light modernization in an information age, it is difficult to imagine the difference in our life. I think that one day, light is also likely to become a carrier for the quantum communication and quantum information.
Light quantum cognition also changes our considerations of energy and clean energy. If there is no light quantum theory, there will be no such concept of solar energy. In the future, the laser is also very important if we can achieve fusion one day. Of course, the laser manufacturing is also a very important field in modern industry. There is also a laser medical treatment and we have a lot of things to do, which are based on the recognition of light.
Here is the laser medical treatment; the laser has also changed the quality of our lives, including lighting and entertainment. It is difficult to imagine modern life without light and with no modern optical scene. It has just been mentioned that the virtual reality created by light technology in the future, which may have a very wide range of applications. In this century, it is very likely that there are human beings who can board the Mars for the first time. To that day, there may be many people in the world who can experience the universe through virtual approaches, which can change our life.
Today, when we come back, it was just about the application of light and light can become a very important scientific method, such as the current photoelectricity may be an indispensable research platform in physics and chemistry. Now the photoelectric bedding is one of the main sources of quantum material cognition. Here are some examples. The cognition of electronic spectrum of light on electronic structure is an important source, so the photoelectric effect has become the source of our cognitive world.
I would like to say that we can really base ourselves on the photoelectric effect and modern laser technology, as well as shoot the atoms and electrons in a microscopic world, to achieve the unprecedented space and time accuracy. In such a way, you can see the interaction between the atoms and electrons, which is the first time to have such a precision to shoot such a movie, because we really meet the requirements of time and space in a microscopic world. Thus, you can also shoot things about some details in a microscopic world, which is helpful to understand it.
We know that the film is very important for displaying the human nature, and we can really start in the microscopic world by using this form to shoot down, so as to understand its details. Furthermore, I think that we will be able to do some applications of the microscopic world in the future, which is also a very great progress in modern science to see such accuracy and the precision of experiment.
Finally, I would like to summarize. We speak a lot of innovation, which actually connects with the cognition. Cognition is the basis of innovation. Hence, a new level of understanding from human to light has been upgraded by the photoelectric effect of Einstein, which has not only offered an important foundation for establishing the quantum theory, but has also laid the theoretical basis for the modern optics, especially the laser invention. It can be said that the information age has close relation to the awareness of quantum. I want to say that the cognition of quantum of light is still the source of innovation in the power generation platform from the basic science to new materials and new energy, from the lighting to entertainment, from the optical communication to quantum communication and the generation of quantum information, from laser manufacturing, light medicine and from imaging to the virtual world. We begin to shoot the real-time film in the macroscopic world, which is a very promising field.What I really want to emphasize is that, it also focuses on the dynamic property of knowledge in an innovative environment, because it is really the main source on the social development.