"Lee, I want you to see my paper."

Arthur Compton opened his briefcase and pulled out a stack of manuscripts.

Li Kangping took the manuscript and read it quickly.

Arthur Compton's paper is titled "The Quantum Theory of X-rays Scattered by Light Elements".

"From the point of view of quantum theory, it can be assumed that any particular X-ray quantum is not scattered by all the electrons in the emitter, but expends all its energy on a particular electron, which in turn scatters the ray in a particular direction, which is at an angle to the incident beam. The bending of the radiant quantum path causes a change in momentum. As a result, the scattered electrons recoil with a momentum equal to the change in X-ray momentum......"

“…… The energy of the scattered ray is equal to the energy of the incident ray minus the kinetic energy of the recoil of the scattered electrons. Since the scattered ray should be a complete quantum, its frequency will decrease in proportion to its energy. Therefore, according to quantum theory, we can expect the wavelength of the scattered rays to be larger than the incident rays. The intensity of the scattered radiation is greater in the direction of the advance of the original X-rays than in the opposite direction, as experimentally measured. The experimental design and experimental results are as follows......"

In the paper, Compton drew a diagram of the experimental design and listed the main experimental data.

Li Kangping said while reading the paper: "Arthur, your experiment looks good. ”

Compton explains, "I built a special X-ray spectrometer, and the X-ray tube was designed and blown myself. The target of the tube is very close to the graphite scatterer, and the tunable quadrant electrometer used for the measurement was modified by Carl and I together, which greatly improved the detection sensitivity of the X-ray scattering experiment, so I got this set of experimental data. ”

The Carl mentioned by Arthur Compton is his older brother Carl Compton, and it looks like his own brothers are in the battle together.

"Wonderful experiment, quite wonderful."

Li Kangping praised and continued to read the paper.

"According to the conservation of energy and momentum, taking into account the relativistic effect, the scattering wavelength is obtained: Δλ = (2h/mc)sin^2(1/2θ). where Δλ is the difference between the incident wavelength λ0 and the scattering wavelength λθ, h is Planck's constant, c is the speed of light, m is the resting mass of the electron, and θ is the scattering angle. ”

"K.P. Lee, published in the Physical Review in February 1921, "Black-body Radiation and Light Quanta", in which he pointed out that, from the point of view of the quantum theory of light, the phenomenon of interference can be related to the collection of light atoms, which are not independent of each other, but coherent."

"I think K.P. Lee's point should be valid. Moreover, I observed that wavelength variations can be explained by the quantum theory of light, and by conservation laws: this close numerical coincidence seems to imply that we should think of the scattering process as a quantum phenomenon rather than a classical law. ”

Arthur Compton writes in a mild tone, frequently using words such as "should", "seem", "maybe", and "perhaps expected".

Li Kangping understands that this "Quantum Theory of X-ray Scattering by Light Elements" is actually the Compton effect.

The Compton effect ---- one of the eternal gods of quantum mechanics.

Matter waves ----- another eternal god of quantum mechanics.

The Compton effect and matter waves are in the same group, so Li Kangping unconditionally supports Compton's "Quantum Theory of X-ray Scattering by Light Elements".

Li Kangping shouted happily: "Arthur, you have done a terrific experiment, you have come up with a great academic point!" That's right, we should think of the scattering process as a quantum phenomenon! The quantum doctrine of light is undoubtedly correct! I'm so happy, Arthur, I'm so proud of you! Hey, is there alcohol in the room, I want to drink! ”

"Li, don't be too happy, I think there are some things in this paper that need to be revised, which is the main reason why I came to New York to meet you this time."

The two had a long talk all night and had an in-depth discussion on academic issues.

The physicists who support the classical wave theory of light, we call it the old school.

The physicists who support the quantum theory of light are what we call the New School.

The quantum theory of light says that light is not only wave-like, but also particle-like, that is, light has wave-particle duality.

Albert Einstein proposed the quantum theory of light as early as 1905, which was supplemented and improved in 1916. Using the quantum theory of light, Einstein perfectly explained the photoelectric effect and gave the photoelectric equation.

Robert Milligan proved the photoelectric effect in 1916 through photoelectric experiments, and it seems that Einstein has triumphed.

Funnily enough, Robert Milligan was a supporter of the classical theory when he did the optoelectronic experiment, and he wanted to prove the correctness of the classical theory by overturning the quantum theory of light through experiments.

Whatever the original intention, Robert Milligan's experimental results are strong evidence for the quantum theory of light.

The main reason why Einstein won the 1921 Nobel Prize was for his research in the field of photoelectric effects.

The quantum theory of light was proved by Milligan's experiments, and Einstein won the Nobel Prize for it, so did Einstein win a big victory?

It doesn't seem to be.

There are still a large number of old-school physicists who firmly support the wave theory of light.

Why is that?

Are they too stupid?

Arthur Compton just said that in this war of fundamental theoretical questions, whoever loses will fall.

You laugh at the old school and laugh at your nonsense.

The succession of academic dynasties inevitably involves fierce struggles, and this struggle is not only purely academic struggle, but also involves other factors.

In his paper, Arthur Compton quoted Li Kangping's paper "Black-body Radiation and Light Quantum", and at the strategic level, Arthur Compton and Li Kangping are strategic allies with a high degree of academic coherence.

In other words, on the fundamental question of the nature of light, Arthur Compton and Li Kangping belong to the new school, they are on the side of Einstein, and they are staunch supporters of the quantum theory of light.

It was dark, and before I knew it, the night had passed.

Li Kangping, who was a little tired, said: "Arthur, your X-ray scattering experiment is a step further than Professor Milligan's photoelectric experiment, you not only take into account the conservation of energy, but also the conservation of momentum. So the question we face is, why did C.G. Darwin write that? ”

C.G. Darwin's attitude is actually more ambiguous, he said that the quantum theory of light and the wave theory of light are like fire and water, and only one of the two can survive. However, C.G. Darwin did not make it clear whether he supported the quantum theory of light or the wave theory of light.

To be sure, C.G. Darwin believed that the law of conservation should be abandoned.

Arthur Compton, on the other hand, based on the law of conservation, wrote the paper "Quantum Theory of X-ray Scattering by Light Elements".

C.G. Darwin's grandfather was arguably one of the most outstanding scientists in human history.

C.G. Darwin, a young British scientist, was a little famous, but nowhere near the level of his grandfather.

Li Kangping and Compton know that C.G. Darwin is just a thug, we can ignore C.G. Darwin, and we must pay attention to the real big man behind C.G. Darwin, Nils Bohr.