Chapter 163 Perfecting the Calculation Method

Start the research from the "asymptotic freedom of quarks" and "quark confinement", this is David Gross's advice to Xu Chuan.

If he was not the chairman of CERN and had some understanding of most collision experiments and analysis data, he would probably not be able to give advice.

After all, this is a field that few physicists have entered.

But he didn't know how much the boy in front of him knew about these two fields.

After all, he was too young.

According to common sense, this age is still in the stage of learning and absorbing knowledge, even if some results can be made in certain fields, it is only relative.

Because his age is destined to lack a lot of basic knowledge in other fields.

But at present, it seems to be inspired?

Perhaps the area where this boy studied in physics has been exposed to these two aspects of knowledge?

In any case, he has great expectations for the boy in front of him.

From the time he learned about him from Witten to the time he stood on the podium to solve the mystery of the proton radius not long ago, Gross saw the talent and talent of this boy.

This is a genius, a real genius.

Whether in mathematics or physics, he has top talent and has made his own way in both.

Many people think that academic or research requires single-mindedness and concentration, but David Gross does not think so.

In his opinion, as long as you like it, you can do it.

Do what you like; dare to ask questions and take risks. Young people should dare to try. You may fail if you try, but you cannot succeed if you don't try.

Moreover, doing what you like is happy even if you fail.

For the young man in front of him, Gross hopes that he can go further.

For someone like him who has devoted his whole life to physics and has half of his body buried in the ground, there is nothing more gratifying than seeing that there are successors in the field of physics.

In the office, Xu Chuan fell into deep thought.

He continued to think along the instructions of Professor David Gross.

He was very clear about the two fields of "asymptotic freedom of quarks" and "quark confinement" mentioned by Professor Gross.

Both of these are knowledge in the field of particle physics.

The former is the result of the old man in front of him winning the Nobel Prize.

It is a magical and counterintuitive physical phenomenon.

In short, its core is that the nuclear force of the nucleus weakens at a very short distance, allowing the quarks in the nucleus to behave like free particles. But when the distance between two quarks in the nucleus increases, the attraction that binds them becomes stronger.

This property can be likened to a rubber band. The longer the rubber band is stretched, the greater the rebound force will be, but when you don't pull it, it will be loose.

This is the "asymptotic freedom of quarks", which can be perturbed by the cross-section DGLAP equation of deep nonlinear scattering in particle physics, thus deriving the discipline of "quantum chromodynamics".

In 2004, three physicists, David Gross, David Politzer and Frank Wilczek, also won the Nobel Prize for this year.

And "quark confinement" is also a physical phenomenon.

It describes that quark particles will not exist alone.

We all know that quarks are the basic units of matter.

Quarks combine with each other to form a composite particle called "hadron".

For example, the most stable particles among hadrons are ‘protons’ and ‘neutrons’, which are the basic units that make up the nucleus of atoms.

Due to the existence of strong interaction, quarks with color charge are confined to other quarks, making the total color charge zero.

The interaction between quarks increases with the distance, so it is impossible to find quarks that exist alone.

Simply put, because of the strong interaction, quarks cannot exist one by one like ‘protons’ or ‘neutrons’.

They always come in pairs, or hug each other for warmth.

For example, protons are composed of two up quarks and one down quark through gluons under strong interaction.

Or the five-quark particles discovered by CERN through LHC last year, etc.

However, what is the relationship between these two theories and the most ideal search decay channel for Yukawa coupling of Higgs and third-generation heavy quarks using mathematics?

Theoretically, these three can be said to be three completely different things.

Even if Xu Chuan stands from the perspective of the physics world twenty years later, these three are not very related.

If we insist on saying that there is a relationship, then it is that the "quantum chromodynamics" derived from the "asymptotic freedom phenomenon of quarks" has a certain relationship in the study of strong interactions.

But things in this area do not seem to be applied to the most ideal search decay channel for the Yukawa coupling between the Higgs and the third generation heavy quarks.

However, a Nobel Prize-level scholar obviously cannot aimless. Since Professor Gross suggested to study from the direction of "asymptotic freedom phenomenon of quarks" and "quark confinement", there must be something hidden in it.

These things can definitely be applied to the most ideal search decay channel for the Yukawa coupling between the Higgs and the third generation heavy quarks.

It's just that he has never seen it.

Physics is so big that even if he is a top physicist who has been reborn after 20 years, it is impossible for him to be familiar with every knowledge point.

Of course, it is more likely that this is just an idea that Professor David Gross has just had in his mind these two days.

This is just like the evolution of organisms. Without external stimulation, organisms cannot mutate and evolve.

Normal physicists will not study this aspect at all.

If he hadn't sent the email to the professor yesterday, the old man probably wouldn't have thought about this problem in his mind.

It is normal that ideas born out of accidents will not be passed down in the future.

Xu Chuan did not struggle with this aspect. He was thinking about how to study the most ideal decay channel from the direction of 'asymptotic freedom of quarks' and 'quark confinement'.

The old man opposite the desk obviously had some ideas in this regard, but he did not say it directly, but gave a hint.

This should be a test for the old man to see his talent or ability in physics.

Even if he couldn't figure out any results in the end, the other party should tell him the complete idea.

But Xu Chuan couldn't just give up his independent thinking. If he couldn't do it when there was already a clue, he didn't deserve to stand at the top of the physics world.

All kinds of knowledge in his mind were quickly turned over, starting from the "asymptotic freedom of quarks" to quantum chromodynamics, from "quark confinement" to the vacuum excitation of the lowest energy state.

A series of knowledge points quickly formed a tortuous but connected clue in Xu Chuan's mind.

Suddenly, he seemed to remember something, raised his head abruptly, and stared at the old man opposite the desk with shining eyes.

"The soft gluon resummation effect of transverse momentum distribution?"

Hearing this, Professor David Gross showed a surprised look and asked in surprise: "How did you think of this?"

He didn't expect that the young man in front of him could find a breakthrough in such a short time.

After receiving the email yesterday afternoon, he thought about it all night, and used the countless collision experiments and analysis data he had encountered at CERN over the years to find a seemingly feasible path, which took no less than five or six hours.

Unexpectedly, Xu Chuan only thought for less than five minutes and found this hidden intersection.

Although there was his hint first, it was too incredible.

The soft gluon resummation effect of transverse momentum distribution can be said to be the most cutting-edge and unpopular field in the current physics community.

This field is used to calculate the color interference effect between the initial and final states of particles.

But in today's physics community, colliders are still looking for new particles and verifying whether the standard model is correct. How can anyone pay attention to the color state interference effect?

There are only a few people in the entire physics community who know something about this.

If it weren't for being the chairman of the CERN Board of Directors, he wouldn't have known about this knowledge.

He was quite surprised that Xu Chuan could find a breakthrough so quickly.

Xu Chuan smiled and replied: "I have learned some calculation methods at the QCD sub-leading level."

Hearing this, Professor David Gross suddenly understood.

The calculation at the QCD sub-leading level is based on the results of the QCD soft-collinear effective theory.

And some of the QCD soft-collinear effective theory involves the knowledge of the soft gluon resummation effect of transverse momentum distribution.

If this is the case, it is indeed possible to find a breakthrough along this clue.

But it must be said that the young man's thinking is really jumping enough to successfully find the breakthrough of the soft gluon resummation effect of transverse momentum distribution along the clue of "the asymptotic freedom phenomenon of quarks".

In other words, his intuition and talent in physics and mathematics are really amazing.

After all, there are many twists and turns in the knowledge points in between. Even if you have learned the calculation at the leading level of QCD, it is not so easy to deduce it smoothly.

It's like playing a game.

Ordinary players only consider the line and opponents in front of them, while high-end players will consider the next move.

And some people have unparalleled talents in the game, and can calculate farther, and even the line can be declared over when the opponent hits the line.

It sounds a bit outrageous, but there are indeed such talented people.

This is the case in the gaming industry, and the academic world is the same.

Some geniuses can return a large number of achievements if you give them a little inspiration.

For example, Newton discovered the law of universal gravitation when he was hit by an apple. And ordinary people will just put the apple into their mouths when they are hit by an apple.

After bidding farewell to his master, Professor David Gross, Xu Chuan went straight back to his hotel room.

With inspiration and enlightenment, the road ahead will be much easier.

Shrinking in the hotel room, he started from the calculation of the soft gluon resummation effect of the transverse momentum distribution, and began to use mathematics to calculate the data of the Daritz diagram in his hand.

I don’t know how long it has been, a cell phone ring suddenly rang in the silent room.

Being interrupted in his calculation, Xu Chuan impatiently picked up the phone from the table, and said "Hello" after answering it.

"Junior brother, the acceptance report meeting for this experiment is about to begin, where are you? You didn’t reply to my message."

The call was from Senior Brother Qi Xishao. Hearing this, Xu Chuan came back to his senses and looked at the time on the lower right corner of the laptop screen. He had been in the hotel room for three whole days without realizing it.

Xu Chuan asked, "Which conference room is it? I'll go there now."

He had to go to this report meeting anyway.

After all, he was a member of the project team. Although he joined in the middle and late stages, he was still a member. It was his duty to attend the report meeting of the scientific research project he participated in.

If someone disagreed with the data analysis part he was responsible for during the report meeting, he had the obligation to explain.

Fortunately, this time, the most ideal search decay channel for using mathematics to find the Higgs and the third-generation heavy quarks has a fixed direction, and the rest of the work can be slowly improved without worrying about the inspiration flying away.

"Report Hall No. 2, it's about to start, hurry up."

Xu Chuan responded, hung up the call, rushed into the bathroom to wash his face, and tidied up his messy hair.

If time permits, it is right to take a shower and tidy up your appearance before going.

But unfortunately, time does not allow it now.

Rushing to the No. 2 lecture hall, the acceptance report meeting had already begun.

As a member of the project team, Xu Chuan had his own fixed position, right next to Qi Xishao.

"Fuck, what have you been doing these two days, little brother? How did you get into this state? Although young people have a lot of energy, they should also pay attention to the frequency and protect their kidneys."

As soon as he sat down, Qi Xishao's voice came over.

He was shocked by Xu Chuan's condition. Although his hair was trimmed, it was shiny and oily, as if he hadn't washed it for several days. His eye circles were dark, as if he had been up for several days and nights. The whole person looked like he had overdrawn more than a dozen times.

Considering that he hadn't seen this little brother in the office for the past few days, he naturally thought that this little brother had gone to play at the Gallic Chicken next door.

Xu Chuan rolled his eyes and said, "What are you thinking about? I've been in the hotel for the past two days. I've got some ideas for my previous ideas, and I've been verifying them these two days."

"The one that searches for the most ideal decay channel for the Yukawa coupling of the Higgs and the third-generation heavy quarks? Haven't you given up yet?" Qi Xishao asked in surprise.

Xu Chuan nodded, and Qi Xishao sighed, "Take care of your health. Scientific research is important, but health is more important. It's not worth it to exhaust yourself."

Although there is no shortage of diligence and hard work in academics, it's rare to see someone as diligent and hardworking as this junior brother.

Qi Xishao thought he was diligent enough, but he also had some other hobbies.

And this junior brother, it seems that he has no other interests besides academic research?

Anyway, in the few months he was in contact with CERN, he didn't see Xu Chuan show other hobbies. Basic activities were related to scientific research, and he was often seen lying in front of the table and calculating for a long time.

It can only be said that there is a reason why he can solve a world-class problem in mathematics and physics at the age of 18.

If such a person doesn't succeed, who will?

Xu Chuan smiled shyly and said, "I'll pay attention."

"Wait, you just said you found a way? Calculated the most ideal search decay channel?"

Qi Xishao sighed, and suddenly, he remembered something, turned his head and asked in surprise.

He just seemed to hear this junior brother say that he had an idea and was calculating it?