Great Country Academician

In the office of Professor Deligne at the Institute for Advanced Study in Princeton, Xu Chuan finished his afternoon study.

He put down the ballpoint pen in his hand, moved his head, and stretched his waist. Suddenly, there was a crackling sound from the joints all over his body, which attracted the attention of other people in the office.

This scene has been the norm here for the past month.

Anyone who came to visit Professor Deligne knew that he had a new student and was currently studying with him.

Some people are very curious about the new student admitted by Deligne. It is obvious that the old professor stopped taking students personally a long time ago, so why did he accept another student this year.

Some people who know the inside story are amazed in their hearts. They have already stood at the top of the mathematics world, but they still choose to return to campus to study with concentration. The perseverance and the dream are so far away that people look forward to it.

In the office, Xu Chuan didn't care about other people's eyes, and sorted out the study books, notebooks and manuscript paper on the table.

In the past month, he has gained a lot in mathematics, not only the knowledge of number theory and differential equations, but also some basic knowledge of algebra and geometry.

Not only that, but he also saw some of Pope Grothendieck's "posthumous manuscripts" from Deligne, some of which were written in French, including the "Draft Programme" and "Theory of Concepts".

These works are what the Pope has sorted out together with other mathematicians in the mathematical community.

But unfortunately, because his research was used in military warfare, the Pope in his later years almost recalled all the copyrights of his books.

For the mathematics community, the manuscript in Deligne's hands is no different from the manuscript before the "Bible" was formed, and its value is immeasurable, not only for collection value, but also for endless academic value.

Xu Chuan got a manuscript from Deligne, which was given to him by Deligne. It was a manuscript related to correspondence. The paper was not thick, only a dozen pages, but it made him ecstatic.

There is nothing more valuable than this.

It's just a little regretful that he couldn't read the original manuscript immediately. This great work written by Pope Grothendieck himself was written in French.

And he had never studied French, so he could not understand this work.

But it doesn't matter, it's just a language, it's not difficult for him to learn, at most one or two months will be enough.

"Mentor, starting tomorrow, I need to take some time off."

After packing up his things, Xu Chuan walked to the old man at the desk with his backpack on his back, and asked.

"sure."

Deligne nodded, and directly agreed to his request, without even asking how long the leave would be and what the leave would be used for.

If it is another student, he may also ask how long the other party needs the vacation time and what to use it for.

But if it is the student in front of him, there is no need for this at all.

Although the student in front of him has only started studying with him for a month, he has already seen the student's desire and love for knowledge.

Such a person, even if no one supervises, will not lose his direction and goal.

After returning from the tutor's office, Xu Chuan didn't go back to the dormitory immediately, but went to the supermarket to buy some food, canned food, instant food, fruit, etc.

He is going to solve the calculation method of the 'Proton Radius Mystery' directly without going out in the next few days.

Mathematics is endless, but the work of the mystery of the proton radius has been slowly perfected for a month, and now it is almost finished.

In order to ensure that there are no problems, Xu Chuan chose to spend a complete period of time concentrating on making an argument on the previous calculation process and perfecting the final ending.

The time he gave himself was a week, and a week, plus his previous work, should be enough.

After buying food and daily necessities in advance, Xu Chuan locked himself in a small dormitory of less than 20 square meters.

In front of the heavy wooden table, Xu Chuan took out all the papers related to the 'Proton Radius Mystery', and conducted a complete inspection from the beginning.

He checked at a very fast speed, and his eyes were almost on the paper, and he didn't go through the detailed calculations one by one.

Because these things have long been familiar to him, he can know whether there is a problem with right or wrong after a short glance.

But occasionally, Xu Chuan would stop his gaze, pick up the pen and calculate on the manuscript paper.

These are some slightly flawed or cumbersome places left over from the calculations in the past. Now, he has a more streamlined method to replace them, which does not affect the final answer, but can optimize the process and reduce the amount of calculation.

If he can go one step further and strive for excellence, he will naturally not give up.

After spending several hours, Xu Chuan sorted out the manuscript paper recording the calculation method of the "Proton Radius Mystery" in his hand from beginning to end, and then continued to improve along the nodes.

Although it takes time to do so, it also has advantages. On the one hand, it can ensure that there are no problems in the previous process, and on the other hand, it allows his thoughts to perfectly adjust to the calculation method of the "Proton Radius Mystery".

This is just like exercising. Before strenuous exercise, warm-up exercises can effectively increase the body's cell activity.

Time passed little by little like this. For a whole week, except for occasional meals and purchases, Xu Chuan never stepped out of this small room of less than 20 square meters.

Using mathematics to analyze the mystery of the "proton radius" was much more difficult than he imagined, especially at the end, he also encountered a rare problem of atomic elastic scattering interface charge interference.

This is a typical physics problem. If you don't have an understanding of particle physics, you won't know where to start.

But fortunately, physics is his profession. In the end, Xu Chuan successfully solved this problem by using the Fourier transform of the three-dimensional spatial distribution of proton charges.

It took two or three days longer than expected, supplemented by the previous months of work, and he finally completed the work.

The ballpoint pen in my hand drops the last point on the manuscript paper:

[Some new formulas for the properties of electrons and protons and their physical meaning Energy-to-charge ratio formula: mC/q=1/2εEds∫.=1/24πrεEr/4πrεE]

【.】

[This method is calculated on the experimental data measured by the spectroscopy experiment method and the scattering experiment of charged particles and protons.]

[The proton body (with a radius of Rp=7.65×10-19m) performs a circular motion related to de Broglie waves around the range of radius Rp = 0.8414×10-15m±0.0019fm at a quarter of the speed of light (that is, the second Hierarchical spin motion). 】

[The second-level spin motion of the proton body forms a proton spin body (radius Rp, =0.8414×10-15m±0.0019fm), and the circumference of its movement is equal to one when the proton body moves at a quarter of the speed of light. de Broglie wavelength. 】

The ballpoint pen in his hand outlined the final message on the manuscript paper, and Xu Chuan stared at the manuscript paper on the table with shining eyes.

After four or five years, he finally perfected this method, and the physics community also has a new method for calculating the diameter of protons, a method based on first principles and mixed with some experimental data. 'False primary calculation formula'.

As for the purely first-principles accurate calculation of proton radius data, no one in the entire physics world can do it yet.

Xu Chuan has never tried it, and he doesn't want to spend all his time on it. Unless he can make more amazing discoveries in the field of proton radius, it won't be worth it.

Most current discussions of atomic structure in physics rely on the much-maligned Bohr model, in which electrons orbit the nucleus in a circle.

That is to say, in the cognition of ordinary people, the structure of atoms should be like the solar system, and the electrons revolve around the nucleus (the sun) like planets.

But quantum mechanics, the doorstep of physics, gives us a more precise, and weirder, description.

"Electrons don't orbit the nucleus!"

Quantum-mechanically speaking, electrons are waves, and they only take on the properties of particles when we do experiments to determine their position.

And when electrons orbit atoms, they exist as a superposition of particle and wave states, with the wave function simultaneously containing all the probabilities of their position.

The measurement collapses the wave function, which yields the position of the electron. Do a series of these measurements, and map out the different positions, and it will produce a blurry orbital trajectory.

In other words, electrons can appear anywhere in the nucleus, even among protons.

It sounds incredible, but from the perspective of quantum mechanics, this is indeed possible.

And this singularity of quantum physics extends to the proton as well.

A proton is made up of three charged quarks bound together by the strong nuclear force. But its boundary is fuzzy, like a cloud containing three drops of water.

Since the boundary of the 'cloud' is fuzzy, how can the diameter be determined?

Physicists do this by relying on charge density, similar to the density of water molecules in a cloud. Once the density of water molecules is above a certain threshold, the diameter of the 'cloud' can be precisely determined.

And the same goes for protons.

A proton is not a ball, and there is no absolutely precise radius. Its radius is the distance from the boundary to the core when the charge density it carries falls below a certain energy threshold.

To measure such a boundary, the difficulty can be imagined.

However, if there is a demand, someone will definitely solve it. The radius of the proton has been estimated through mathematical methods early in the development of physics. Then, with the passage of time and the development of various high-precision physical equipment, this number has been accurately calculated. The measurement came out and was finally determined to be 0.879±0.011 fm femtometer (1 femtometer=10^-15 meters).

Of course, this is just an "average" taken from many different measurements around the world, and enough error conditions have been taken into account.

Before 2010, this number was adopted by CODATA (International Committee on Data for Science and Technology) and determined as the radius of the proton.

But later, in 2010, muon spectroscopy challenged this value.

In an experiment by physicists at the Max Planck Institute for Quantum Optics, they used meson hydrogen, an experimental material in which an electron orbiting the nucleus is replaced by a meson.

Since it is nearly 200 times heavier than an electron, its orbit is much smaller, so its probability of being inside a proton is much higher (10 million times).

And because it is closer to the proton, this makes the measurement technique 10 million times more sensitive.

The team of physicists had just hoped that the proton radius they measured would be roughly the same as previous experiments, making the 0.8768 femtometer figure more certain.

At that time, no one thought that there would be any surprises in this experiment. After all, in theory, there is no other difference between electrons and muons except mass and lifetime.

However, if there are no accidents, there will definitely be accidents.

In this experiment, the proton radius they measured was significantly lower than the value given by the International Committee on Data Science and Technology (CODATA), and it was even as low as an astonishing 0.833 femtometer at the lowest point.

Even if the effect of energy level changes caused by the electrons and protons outside the nucleus is removed, and then the average number and error are taken, the radius value is still 0.84184±0.00067 fm.

The results of this experiment caught the researchers at the time by surprise. After all, the radius of the proton involved the base of the physics building.

After the results were released, more physicists invested

But since then, more spectroscopy experiments have further confirmed the relatively small proton radius.

Experiments in various countries have shown that the radius of the proton should be smaller than before.

What is puzzling is that the proton radius obtained through scattering experiments always stays at around 0.8768 femtometer.

That is to say, there is a 5% difference between the two different test methods, and this 5% difference is called the "mystery of the proton radius".

And as of today, this mystery has finally been solved.

Of course, the premise is that Xu Chuan's calculation method is correct.

At the desk, Xu Chuan threw away the ballpoint pen in his hand, went to the bathroom to wash his face, and then threw himself on the bed. After a while, there was a slight snoring sound.

In order to perfect the method in his hand, he has not closed his eyes for more than thirty hours. The closer to the end of the mystery, the more excited he is, which is enough to fight against physical exhaustion.

Now the result is finally obtained, and the thread hanging in my mind is finally broken.

This time, Xu Chuan slept from four o'clock in the afternoon until three o'clock in the morning the next day before waking up.

After getting up and taking a shower, Xu Chuan walked to the desk while wiping his wet hair with a towel.

The messy manuscript paper on the desk records what kind of trial the place has experienced before.

Picking up a piece of manuscript paper from the table, Xu Chuan's eyes fell on the final answer.

Judging from the results calculated from the current data, a small proton radius will be the answer to the particle physics community.

People have observed through countless experiments that the charge radius of the proton is not as large as imagined.

And this also means that before 2010, the data observed by the entire physics community were wrong.

In other words, there was a huge error in their experiments, which led to this result.

At present, he still doesn't know where the error comes from, but mathematics can't lie, and the problem does exist.

Thinking of this, Xu Chuan smiled.

If this answer is released, I am afraid that it will cause an uproar in the entire physics world.

After all, nowadays, there are many people who think that the proton charge radius is a large radius, which is 0.8768 femtometer.