"Now, Professor Arthur Compton." Mr. Harris, the moderator of the meeting and a member of the National Academy of Sciences, said.

Arthur Compton straightened his bow tie and then said loudly: "According to the classical theory, when X-rays meet matter, they affect the electrons it illuminates, and the observed scattering is the sum of the effects of all electrons. From the perspective of quantum theory, we can imagine that an X-ray quantum is not scattered by many electrons in the radiator, but acts on a certain electron with all its own energy. This electron causes the ray to shoot in a direction at a definite angle to the incident ray. ”

"This bend in the path of the radiation quantum will cause a change in its momentum. As a result, the electrons that cause scattering will recoil with momentum equal to the value of the X-ray momentum change. The energy of the scattered ray should be equal to the energy of the incident ray minus the repulsive energy of the scattered electrons, and since the scattered ray must be a complete quantum, its frequency also decreases by the same rate as the energy change. In this way, we can be convinced by quantum theory that the scattered X-rays have a wavelength greater than the incident rays. ”

"The momentum of X-ray quanta plays a role in causing scattered electrons to move at an angle of up to 90 degrees with the incident X-rays. The whole system has to maintain a forward momentum value, so the electrons must gain a portion of this forward momentum. It is known that the radiation of a moving object has the highest energy along the direction of motion of the object. So we would expect that the intensity of the scattered radiation in the direction of the primary X-rays should be greater than that in the opposite direction. Our experiments prove this. ”

Arthur Compton frequently uses the sentence formation format of "because-so", his logic is very clear, he first theoretically argues for self-consistency, and after explaining the theoretical problem clearly, Arthur Compton only uses one sentence to summarize his experiment---- our experiment proves this.

Attendees had seen the papers of Arthur Compton and Duane in advance, and Arthur Compton did not need to state the details of his experimental design and operation from beginning to end, he only needed to get to the point.

Li Kangping, Wu Youxun, Carl Compton, Woodgate, Mathis and other participants showed appreciative expressions, and they highly recognized Arthur Compton's academic views and experimental evidence.

Duane, Jefferson, Carter and other participants were half-positive and half-negative, and they recognized Arthur Compton's self-justifying theoretical statements to a certain extent, but questioned Arthur Compton's experiments.

Robert Milligan, Wiesen, and others remained on the sidelines, just listening, and did not express any opinion for the time being.

It was Duane's turn to debate, and he said: "First of all, I think that the quantum theory and the quantum theory of light are valid, which is a prerequisite. There is no doubt that Professor Arthur Compton is a good debater, but the truth is not on your side. ”

"Professor Arthur Compton, your experiments have many flaws--- even errors. First, your experimental data cannot explain the low frequency of fluorescence radiation. Second ......"

"Professor Duane, I can explain!" Arthur Compton interjected impatiently.

"I'm sorry, I'm not done yet." Duane shrugged and said, "Second, you get a scattering curve that only satisfies the formula you unilaterally created, but not the universality formula that people recognize." Third ......"

Duane listed a few irrationalities that he had identified in the Compton paper and refuted them with a clear attitude.

Arthur Compton, who came prepared, explained what Duane thought was unreasonable.

However, no matter how Arthur Compton defended it, scholars such as Duane, Jefferson, and Carter never accepted Arthur Compton's explanation.

"Looks like we can't continue talking!" Arthur Compton said helplessly and annoyed.

30-year-old Arthur Compton is also a young man, a young man with a short temper, but not so grumpy as to not speak of virtue.

The younger Li Kangping did not come to be a tool man, he organized his language and said loudly: "The crystal used by Professor Arthur Compton in his experiments is a transparent calcite, so that even for the first level of the spectrum, it has a fairly high resolution. Please turn to pages 23~24 of Professor Arthur Compton's paper, and we can see that curves B, C, and D are scattered rays of 45 degrees, 90 degrees, and 135 degrees respectively from the primary rays. ”

"From these curves, it is clear that when a single wavelength of X-ray is scattered by graphite, it will be divided into two different parts, one with the same wavelength as the original ray and the other with a larger wavelength. Professor Arthur Compton's experimental error is less than 1 arc minute, i.e. 0.001 angstroms, which is not a problem, and this accuracy fully supports the conclusions of Professor Arthur Compton's experiment. That is, the wavelength of the variable ray lengthens as the scattering angle increases, as predicted by quantum theory. Obviously, Professor Arthur Compton gave sufficiently detailed and convincing experimental evidence, didn't he? Li Kangping supported Arthur Compton with reason.

Arthur Compton gave him a grateful look, and Carl Compton slapped him hard.

"Dr. Li, it seems that you are also a master debater." "We found that Professor Arthur Compton, in his paper, quoted Dr. Lee's book Black-Body Radiation and Quantum of Light, published in February 1921. Let me think, Dr. Lee seemed to be an undergraduate at Columbia College at that time? ”

"Professor Duane, is my thesis directly related to my academic qualifications at that time?" Li Kangping's feelings for Duane are quite complicated.

At the APS annual meeting in the summer of 1921, Duane strongly supported Li Kangping and Woodgate's "Silver Atomic Beam Method to Verify the Theory of Space Quantization".

At the review of The Wave of Matter in early 1922, it was Duane who made the suggestion, saying that since we could not overturn the Wave of Matter, we should allow the publication of The Wave of Matter.

Duane is the chair of the Division of Physics at the National Academy of Sciences, and his words carry weight.

With the support of Duane, "The Theory of Space Quantization Verified by the Silver Atomic Beam Method" and "Matter Wave" were both as Li Kangping wished, and these two papers were published at the right time.

On the matter, in the two academic cases of "Silver Atomic Beam Method Verification of Space Quantization Theory" and "Matter Wave", Li Kangping is grateful to Duane for his active cooperation.

However, in the case of the Compton Effect, Li Kangping and Duane stood on opposite sides.