walk into unscientific

Chapter 629 Look what we found?

Before half an hour.

Xu Yun is still feeling a little bit emotional about how Zhao Zhongyao and Gell-Mann missed each other, after all, these two are really quite alike.

And although Xu Yun didn't like Gell-Mann as much as he did Weinberg, he couldn't say he disliked him - among the many big guys, Gell-Mann was considered one of the more friendly to China.

For example, he often comes to China to give lectures, and he only talks about academics and not politics, nor does he belittle the Chinese scientific community.

There are other physicists who have been to China more often than him, but firstly, their status is not as good as his, and secondly, these people are basically foreign academicians from China.

And many so-called foreign academicians.
Not to mention they are all about money.

At least except for R. Clough and David Gross, two foreign academicians who hardly ask for anything but have been donating to China, the rest of the foreign academicians basically ask for something.

For example, they are either the link to maintain the relationship between universities, or they have some cooperation with certain institutions, or they are simply mascots.

Only Gell-Mann is neither a foreign academician nor has an industry in China. He often comes to China to give a lecture to give some knowledge and then leaves—and the appearance fee is really not high.

For example, when he came to China in 12, he only charged 5000 US dollars for a lecture, which was cheaper than his lectures at Ivy League schools.

Therefore, Xu Yun's view of Gell-Man has always been neutral and friendly, especially after Gell-Man's death, the aura of the deceased gave Xu Yun a little extra respect.

But what Xu Yun didn't expect was that.

Now it seems that Mr. Gelmangai in this timeline may not be able to reach the heights of the original timeline.

after all
The concept proposed by Zhu Hongyuan is infinitely close to the quark model.

That's right.

The quark model—and it is also some concepts independent of the straton model.

Well known.

The strong force between quarks and gluons gets weaker not only over tiny time and distance intervals, but also because of huge changes in energy and momentum.

These two behaviors are two aspects of asymptotic freedom, and the quantum mechanical equations in later generations of QCD can be used to deduce the other from one of them.

The rare and huge changes in energy and momentum will lead to an astonishing phenomenon, which was even recognized as a main feature of ultra-high energy interactions in Xu Yunlai's later generations.

That is.
Injection phenomenon, the English name is jet.

It is no exaggeration to say.

The jet phenomenon reveals the essence of QCD, showing quarks, gluons and their fundamental interactions in an extremely intuitive and visible form.

Students who have watched "Into Unscience" should know it.

A neutron is made up of two down quarks and one up quark.

The π meson is composed of up and down quarks and their antiparticles.

A proton, on the other hand, is made up of two up quarks and one down quark.

In some high-speed collisions, the quarks might break free from their usual surroundings, gaining a lot of energy and momentum, and leaving the protons.

However, isolated quarks cannot continue to exist, because all quarks carry "color charge"-which can be understood as a physical quantity similar to electric charge.

This non-zero color charge disturbs the balance of the color gluon field, so the quarks radiate gluons, releasing energy and momentum.

These radiated gluons then radiate other gluons, or quarks and antiquarks, again.

Thus.

The initial stimulus eventually leaves behind a trail of quarks, antiquarks, and gluons, which in turn condense into protons, neutrons, and other hadrons.

This is a very complicated process, a bit like a mother giving birth to a daughter, and the daughter giving birth to a mother-this is the chaotic structure brought about by asymptotic freedom.

Then in this case.

All particles in the jet will tend to move in the same direction.

Finally, the accelerator's detection equipment will observe the trajectories of many particles in a narrow cone-shaped space. This image is the jet-to put it bluntly, it is the shape of the spray fighter after eating too much Wallace.

And because energy and momentum are conserved, so the energy and momentum of all the particles in the jet add up to be the energy and momentum of the initial quark.

Jets are a perfect gift for physicists because they encode information about the energy and momentum of the initial particle.

In a sense, the jet is the embodiment of these particles.

in the original history.

The discovery of the three jets was made by Mr. Ding Zhaozhong, more than ten years later.

At that time, Ding Zhaozhong led a team to discover a new elementary particle at Apuchin National Bluhaven Laboratory. This new particle is very unique, uncharged, and has a lifespan 1000 times longer than the new particles discovered one after another in recent years.

So Ding Zhaozhong named it J particle. The word J is very close to Ding, and its meaning is self-evident.

When this particle was discovered, it also verified the correctness of the quark model proposed by Gell-Mann in 1964.

Another coincidence is.

On the same day, the Richter team at the Stanford Linear Accelerator also discovered a new particle, named the ψ particle.

What's even more interesting is that these two kinds of particles are actually the same thing, but both groups are humbly unwilling to compete for ranking and naming rights. Instead, they use the other party's name to call the new particle.

Therefore, this particle is still called the "J/ψ meson" and is the only particle with two letters. Ting Zhaozhong and Richter also jointly won the Nobel Prize in Physics in 1976.

Also, since mesons are mentioned, here is another very funny joke:
If you search the question [Is a meson an elementary particle] on Baidu, you will find that the answer is actually [Yes].

What's even more ridiculous is that when you click on the answer, you can suddenly see a sentence hanging at the top:

[A meson is composed of a quark and an antiquark corresponding to it, and they are connected together through the strong interaction force to form this kind of composite particle] — Don’t you find the last four words dazzling?
These days, a certain browser is really getting more and more outrageous, it is rogue and anti-intellectual, and it is almost as good as Visual Huaxia.

The line of sight returns to reality.

Of course.

The energy level of the J particle collision discovered by Ding Zhaozhong is 3.1GeV, far exceeding the magnitude of the current tandem electrostatic accelerator.

Therefore, now Zhu Hongyuan and others will definitely not be able to find specific particles, they can only discover phenomena.

But don't forget.
Zhu Hongyuan and others already had the prototype of the stratotron model at this time.

Although he did not see the actual J particles, he would definitely connect the particles he imagined with the stratoton model, that is, quarks.

In other words.

This phenomenon can be a strong support for the straton model!
This is much more important than the J particle. After all, the J particle is just a subatomic type of meson, not even an elementary particle.

But what the straton model affects is the entire basic particle framework!
A bed and a foundation are important, and a fool can tell the difference.

And just as Xu Yun was thinking about it.

Zhao Zhongyao on the side also spoke. He touched his chin thoughtfully and asked Zhu Hongyuan:
"Comrade Hong Yuan, do you mean that under the hadron, there is a kind of smaller particle?"

Zhu Hongyuan pondered for a moment, but didn't make his words too absolute:
"How can I say it? If it is smaller than a hadron, it must not have escaped - after all, it was knocked out from the inside of the proton, and the proton is also a kind of hadron."

"However, it is not known exactly how much smaller it is than ordinary hadrons. What is certain at present is that its state must be very unstable."

"Either it can't exist on its own for some reason, or it decays in a very short time—even at the particle level, which is still very short."

"Of course, the premise of the above guesses is that the particle is not an imaginary virtual object. In short, I personally think that this probability is very high-it just fits some concepts discussed in our atomic energy group at the beginning of the year."

Upon hearing this, Zhao Zhongyao and Wang Ganchang looked at each other, and then asked Zhu Hongyuan:
"Comrade Hong Yuan, are you referring to the review of the meta-hadron model submitted by the Institute of Atomic Energy this year?"

Zhu Hongyuan nodded frankly. This question cannot allow him to be conservative, and he admitted neatly:

"That's right, it's the meta-hadron model."

Zhao Zhongyao was silent for a moment.

The Yuan Qiangzi mentioned by Zhu Hongyuan and Zhao Zhongyao is the straton model that Xu Yun is familiar with, but it has not been renamed as a stratum in this period, and it is called [Yuan Qiangzi] verbally and in documents.

be honest.

Zhu Hongyuan's explanation is not supported by any data, and it is more of a theoretical derivation.

But at least from Zhao Zhongyao's perspective, this statement can indeed explain the injection phenomenon.

Seeing that many people at the scene looked dazed, Zhu Hongyuan coughed lightly and took the initiative to introduce this Yuan Hadron model:
"Comrades, I don't know if you understand the eight-fold method proposed by Mr. Gell-Mann and Mr. Neyman at the beginning of this year, using the SU(3) symmetry of the strong interaction to classify hadrons?"

"Eightfold Law?"

Old Guo who was on the side was slightly startled when he heard the words, and immediately thought of something, and recalled:
"Is that the method of assigning different singular numbers to different particles and combining eight particles to form a stable state?"

"If I remember correctly, there are papers on this concept in the batch of foreign language documents we retrieved from Guide County."

Zhu Hongyuan nodded to Lao Guo and said:
"That's right, that's the way."

"Gong Guo, our Institute of Atomic Energy obtained this paper in February this year. At that time, according to the discussions among the members of the group, everyone thought it was a very interesting concept."

"So we had a free discussion based on this idea, and finally everyone came up with a model that...well, it's kind of like an onion that can be peeled off layer by layer."

"Isn't there a concept of Yuan in our Chinese culture—for example, people have vitality or something, so we called this model Yuan Qiangzi."

mentioned earlier.

Lao Guo and the others retrieved as many foreign language documents as an iron box. There is a time span for the accumulation of these materials, that is, they will be "delivered" only when a certain amount is full.

Therefore, although these materials are precious, they are less time-sensitive.

However, Zhu Hongyuan and his Institute of Atomic Energy are located in the capital, and it is not difficult to get one or two journals in time through Mao Xiong's scattered connections.

So before Lao Guo and the others received the foreign journal, Zhu Hongyuan and the others had already seen Gell-Mann's paper and even brainstormed.

Eightfold method.

This is a theory of strong symmetry of action proposed by Gell-Mann at the beginning of this year based on the idea of ​​symmetry.

He pointed out that strongly interacting particles should satisfy SU(3) symmetry, which corresponds mathematically to the SU(3) group.

Considering the reading needs of some students who are stupid and eager to master knowledge, here is a brief explanation of the concepts of several groups:
in particle physics.

The three groups SU(1), SU(2), and SU(3) are the foundations that must be mastered.

SU(1), SU(2), SU(3) are all Lie groups from a mathematical point of view, and from a physical point of view, they apply a transformation to the system, so that the system has a certain indeformation under this transformation .

These three groups are all their own geometric structures as Lie groups in mathematics. It can be imagined that they are all smooth geometric bodies with their own dimensions.

From a mathematical point of view, this dimension is the dimension of the tangent space and can be calculated specifically. For example, SU(2) is 3-dimensional and SU(3) is 8-dimensional.

This dimension has a very clear physical meaning, which is the dimension of the mediator in the interaction, or the type of mediator.

For example, the only kind of mediator in electromagnetic interaction is photon, so its corresponding gauge field can be U(1).

And the mediator of weak interaction has three kinds of W+, W-, Z, so it can be speculated that the gauge field it corresponds to is SU(2), because SU(2) is 3-dimensional.

That is.
The electromagnetic force corresponds to the U(1) group, the weak interaction corresponds to the SU(2) group, and the strong interaction corresponds to the SU(3) group.

In the SU(3) group, there is another 8-dimensional representation, that is, eight generators.

Therefore, the eight-fold method means that every 8 particles with similar properties can be filled in the 3-dimensional representation of the SU(8) group. It divides the strongly interacting elementary particles with similar properties into groups, and thinks that each group member should have 8.

The meson octet and baryon octet in particle physics are all in the category of the octet method, and later it was extended to the decaite.

So the X sub-X double state you see is essentially a derivative of the eight-fold method.

Of course.

At present, the eight-fold law is still very controversial, so some experts soon put forward different views:
"SU3 group? Comrade Hong Yuan, according to what you mean, the so-called Yuan Qiangzi is not one or two, but eight?"

"If there are so many so-called meta-hadrons, how to solve the CP violation property? - the simplest question, in this situation, the kernel of the homomorphic mapping must be two-to-one in mathematics gone?"

The scholar who spoke was Wang Zhuxi, who was also a well-known physicist in China and one of the first batch of academic committee members in China.

However, the direction of Wang Zhuxi's previous work was mainly on the education side, and the intersection with Zhu Hongyuan is not too deep.

Hearing Wang Zhuxi's question, Zhu Hongyuan smiled slightly:

"Comrade Zhuxi, I can answer your question."

I saw him pick up the paper and pen from the table beside him, and quickly wrote on the table while explaining:
“竹溪同志，同态映射的本质其实就是幺正矩阵的映射验证，只要能证明SO(3)群的元素都可以映射到行列式为1的2X2矩阵D1/2(α，βγ)上就可以了。”

"According to the definitions of SU(2) group and SO(3) group, SO(3):={O∈GL(3, R)|OTO=13, det(O)=1}, SU(2):= {U∈GL(2, C)|UU=12, det(U)=1}."

“接着找一个三维矢量 vv=(v1，v2，v3)，可以利用泡利矩阵将其映射成一个 2×2无迹厄米矩阵，即 vv→rr=viσi=(v3v1iv2v1+iv2v3)，这个映射的逆映射为 vi=12tr[σirr]，并且有 det(rr)=|vv|2，以及 12tr(rr2)=|vv|2”

"This unscented Hermitian matrix can represent the algebra on the SU(2) group, then the adjoint action of the SU(2) group on this algebra is rr=urru. Where u∈SU(2)"

"Then a representation in a three-dimensional real vector space is induced, v′i=12tr(σirr′)=12tr(σiuσju)vj, v′i=Rji(u)vj, therefore, Rji(u)=12tr(σiuσju) "

"In this way, we only need to prove that R(u) ∈ SO(3), our idea is."

Looking at Zhu Hongyuan, who was eloquent and eloquent, Xu Yun couldn't help revealing a trace of subtlety.

Is this a coincidence?

To know.

The proof of group theory in homomorphic mapping in the later Huaxia quantum field theory, the main "operator" is Zhu Hongyuan
However, Zhu Hongyuan compiled that set of books in the mid-80s. Now it seems obvious that this is another achievement that was buried because of the international blockade.

After ten minutes.

Under the gaze of everyone, Zhu Hongyuan wrote the last paragraph:

"According to the definition of kernel space, the kernel of this homomorphic map is H={u∈SU(2)|R(u)=13}, therefore, urru=rr is required, which is true for any rr."

"According to Schur's lemma, u=λ12, where λ is a constant, and because det(u)=1, so λ=±1. Since R(u)=R(u), and the kernel of this map is { 12, 12}, which proves that this homomorphic mapping is two-to-one mathematically.”

"."

Looking at the calculation result in front of him, Wang Zhuxi also fell silent.

Zhu Hongyuan actually deduced it?
And looking at the situation, it seems that he had a specific calculation idea a long time ago?

However, after being quiet for half a minute, Wang Zhuxi couldn't help but touched his chin and said:

"Comrade Hong Yuan, I didn't intend to raise an argument. It's just that we are engaged in physics research. It seems that it is not enough to deduce the results purely from the mathematical results, right?"

"If there are no clearer experimental results, I still have my opinion on your meta-hadron model."

Hearing this, Zhu Hongyuan also showed some embarrassment on his face.

He naturally knew that Wang Zhuxi was not targeting him. After all, mathematics and physics were indeed two subjects.

Although there is a saying that everything is number, this essence is actually logically self-consistent, but mathematics is also logically self-consistent.

At least for now, Zhu Hongyuan does not have enough evidence to support his theory.

However, there was some silence at the scene.

On a table not far from the crowd, a voice suddenly sounded:
"Ah, that's weird"

Note:
I was coding in an Internet cafe late at night. The big guy next door took off his shoes and socks and kept his feet bare (it didn’t smell like anything and he didn’t raise it to the table). I hesitated for a while but didn’t do it because of my personal image.
(End of this chapter)