Students who were meson coils in their previous lives should all know this.
Most composite particles are generally composed of 2-3 quarks.
For example, mesons are composed of one quark and one antiquark, while baryons are composed of 3 quarks or 3 antiquarks. They are called traditional hadrons.
But there is another type of particle that may be composed of a mixture of 4 or 5 quarks or quarks and gluons.
Because they are relatively rare, they are also called strange hadrons, or strange hadrons, depending on each person's naming habits.
At present, one or more kinds of strange hadrons are discovered almost every year or even every month.
The main way to analyze the structure of a strange hadron is actually very simple.
Generally, the invariant mass spectrum of the quark elements is first analyzed, and then the component quark model and the Dyson Schwinger equation are used to analyze the scale. Basically, the composition of the specific structure can be determined.
So for Witten.
Even the more special four-quark or even five-quark particles only shocked him to that extent and could not be that outrageous.
Come to Witten.
The next process is nothing more than introducing the function of the gluon field into the graph group, simplifying a bound state through QCD, and then determining the particle structure. Everyone is happy and has a good time.
As a result, the gluon field function was routinely introduced to eliminate the 'chain' influence of the two particles.
The tip of Witten's pen suddenly paused, and his breathing suddenly became a little faster.
After coming back to his senses.
Witten took a deep breath and quickly started writing again.
Swish swish——
As the lines of characters appeared, Witten's fingers holding the ballpoint pen began to tremble slightly.
Suddenly.
Being so excited, Witten lost his balance and fell heavily to the ground.
Snapped--
The report in his hand was also scattered.
The sound of Witten landing quickly attracted the attention of several people around him. Academician Pan quickly came to Witten's side immediately, reaching out his hand with concern to help him:
"Professor Witten, are you okay?"
However, what surprised Academician Pan.
Witten did not accept his support, but turned over and adjusted his glasses awkwardly. He knelt on the ground, supported his upper body with both hands, and quickly searched for something.
Looking at this posture, I feel like he will shout loudly that physics does not exist in the next second.
See this situation.
Academician Pan couldn't help but have a trace of astonishment in his eyes.
What are you doing?
But soon.
The astonishment in Academician Pan's eyes disappeared, replaced by a look of inquiry and solemnity.
It is obviously impossible for a big boss like Witten to suddenly lose his mind. In fact, Witten is a scholar who cares about his image. He even hired a life butler to help him take care of his appearance.
He must have discovered something when he lost his composure at this time.
some
It was something that even he found difficult to accept the first time.
More importantly.
This enhanced gluon field has no known parameters for reference, so everyone on the scene and even the backstage of CERN or the Academy of Sciences have to calculate the parameters themselves.
So at least for this moment.
Except for Witten itself, no one at the scene knew what Witten was looking for.
Of course, this sentence is from the perspective of Academician Pan.
If they were looking down from a God's perspective, Lu Chaoyang and Christine in the tenth row should be able to guess what Witten was looking for - they discovered it even earlier than Witten.
It's a pity that even people of Academician Pan's level cannot open the entire map and grasp every detail of the overall situation. Naturally, there is no way to know this situation at this time.
One minute later.
Under the gaze of various inexplicable eyes on and off the field, Witten finally found the report he was looking for.
He quickly grabbed the report, flicked the non-existent dust on the surface of the report, trembled slightly at the corners of his mouth, and knelt on the ground to read.
Upon seeing this, Academician Pan hesitated for a moment and gave Xu Yun a look that said, "Go and put away the other papers on the floor."
He came behind Witten and said:
"Mr. Witten, why don't you sit back first?"
Academician Pan’s original intention was to advise Witten to sit back in his chair. After all, the live scenes were being broadcast live simultaneously.
Witten's actions are not a good thing either for the organizer of the Academy of Sciences or for his own image.
And just as he spoke.
Academician Pan's eyes inevitably glanced at the content on the manuscript paper held by Witten, and he subconsciously made an analysis:
That is a quark fitting equation that removes the influence of the gluon field. It corresponds to the oscillation peak in the report and is the final mathematical expression.
Only a math master like Witten can calculate this result so quickly.
And the moment I saw this formula.
The second half of Academician Pan's words got stuck in his throat, and he was stunned for a moment:
"This is this"
At the bottom of the Witten manuscript paper, there is a paragraph of wet handwriting written:
【LM=∑iiνQ RνLi+12MνRνRcQ+(c2(iφk)+ωk2cφk)iωk((iφk)φkφk(iφk))】
At this moment.
Academician Pan had only one thought left in his mind:
No wonder Witten loses his composure.
at the same time.
Although the computing power of these big guys at the scene is inferior to that of Witten, there are also excellent mathematicians like Tehuft.
In addition, the whole process is not very complicated in terms of calculation amount - after all, it is just a calculation of a gluon field.
Although the Witten is fast, it is not so exaggerated that it leads everyone by more than ten minutes.
Therefore, while Witten was looking at the report, some big shots also came up with the results one after another.
"."
With the release of the final form expression, the area in the first row once again fell into a somewhat subtle atmosphere.
After a while.
It was Mr. Yang who spoke first:
"A fermion operator, a variable valence description, the oscillation peak signal can be transformed through the conjugate matrix"
"So everyone, what we found this time is actually two."
"Supersymmetric particles?"
After a few seconds.
Tehuft, Higgs, Polyakov and others nodded slightly at the same time.
See this situation.
brush--
Throughout the press conference, hundreds of theoretical physicists once again stood up from their seats in shock, stretching their necks forward to get a clear view of the first row.
In the live broadcast rooms of major websites, for the seventh time, there were dense question marks:
【? ? ? ? ? ? 】
Lu Chaoyang and Kristen in the tenth row looked at each other, and the two exhaled a somewhat complicated breath:
"As expected."
They thought of this model a long time ago, but they have not made accurate progress in calculation. It can only be said that the idea is a little faster.
And Suzuki Atsushi, who was sitting not far away from Mr. Yang and others and had been watching with cold eyes before, his mind was also blank at this time:
Supersymmetric particles?
How could it be it? !
Super symmetry.
This is a very controversial mathematical structure in theoretical physics.
Mentioned earlier.
The so-called supersymmetry theory is actually very simple in interpretation, which means that every particle has its supersymmetric partner.
That is, fermions must have a companion that is a boson, such as gluons and gluinos.
In turn, the companion of a boson must be a fermion.
At the same time, this theory can support the superstring model to a certain extent and is a very cutting-edge theory.
But across the entire theoretical span, the emergence of supersymmetry theory is far more than what it seems.
The first thing to make clear is.
Throughout the history of human physics, any new theory proposed is driven by physical motivations or needs.
These motivations can come from the contradiction between old theory and experiment, or from the inconsistency of the old theory itself, or even from the drive of pure mathematical facts.
For example, the quark model mentioned before.
It was a framework that was created because the physics community at that time discovered that there was a structure inside the proton, and something was needed to explain the inside of the proton.
What is easier to understand is the heliocentric theory. One of the main reasons for the emergence of this theory is that the geocentric theory itself is not very self-consistent.
The "motivations" for the emergence of supersymmetry theory mainly include three points:
dark matter demand,
The maximum possible space-time symmetry,
and specification levels.
Of these, dark matter requirements are best understood.
To put it bluntly, the physics community couldn't find dark matter for a long time, so they proposed a particle model called superneutraton through the supersymmetry theory.
Now that the Academy of Sciences has discovered Pangea particles, in a sense, this demand has been infinitely weakened or diluted.
So what really matters are two and three.
The maximum possible space-time symmetry is a concept related to the S matrix element.
The S matrix element is the core of quantum theory. The research conducted by Yang Lao, Weinberg, Glashow, and Gell-Mann is actually mathematically inseparable from the S matrix element.
In 1967.
Sidney Coleman and Mandurah proved a theorem:
The largest space-time symmetry group that the S matrix element can have can only be the Poincaré symmetry group, which is the famous Coleman-Mandura theorem, which prevents people from trying to embed the Poincaré group into a larger symmetry group.
But the Coleman-Mandura theorem has a problem that seems to be fatal in later generations:
It assumes that Lie algebraic relations between all generators of a symmetry group can only be commutators.
In other words
All generators can only be of the Bose type - but there is no particular physical reason for this assumption.
For example, if you demonstrate a situation through data:
Compared with other types of novels, Xiaobai's readers have a larger audience - this sentence is actually correct.
But then you use this as a foundation and make another assumption:
The fire book can only be written in plain English.
This sentence is actually relatively unreasonable. Although the proportion of Xiaobai texts in the book of fire may be 70 to 80%, it is still different from the word "can only".
So in 1975.
This assumption was abandoned by Haag, Lopez-Zanski and Zonius, who generalized the largest space-time symmetry group from the Poincaré group to the super-Poincare by allowing the introduction of Fermi-type generators and the Lie algebraic relation of anti-yieldors Laiqun.
And this introduction is undoubtedly correct in the eyes of later generations.
As a result, a problem arises:
The definition of "irreducible representation" appears to be different.
The irreducible representation of Poincaré algebra naturally gives the definition of elementary particles in the Standard Model.
The irreducible representation of super Poincaré algebra gives the definition of all elementary particles in supersymmetry.
For purely theoretical reasons.
Since the largest space-time symmetry allowed by mathematics is the super-Poincaré symmetry, there is no reason to believe that nature would not choose it and only choose the smaller Poincaré symmetry.
This gives the second motivation for the emergence of supersymmetry theory in the purely theoretical scope or the purely mathematical scope.
As for the normative level, this is the 'motivation' of the experimental phenomenon.
Mentioned a long time ago.
Although the Higgs particle was only officially captured in 2012, its mass has been locked in a rough range for a long time.
That is 120-130GeV.
When this number was calculated, almost all physicists had a question:
Oh my god, isn’t this thing too light?
Because in particle physics.
When calculating the self-energy correction of a particle f with mass mf to the Higgs particle, after the infinite part is eliminated through renormalization, the remaining finite part is the mass correction to the Higgs particle.
But this finite part is proportional to mf, not proportional to the mass of the fermion itself like fermions with chiral symmetry protection.
This means that if f is very heavy, the mass of the Higgs particle will be greatly modified, and it can even be much greater than its physical mass.
The most representative one is the GUT energy standard.
If there is a new particle on the GUT energy scale, the new particle will bring a radiation correction to the Higgs mass that is much larger than the electroweak energy scale.
The physical mass of the Higgs particle is only 125 GeV, which means that the two large numbers of the radiation correction and the tree diagram mass of the Higgs particle need to be very finely cancelled, in order to give exactly the physical mass of only 125 GeV.
This unnaturalness, which requires fine adjustment, is clearly a matter of normative hierarchy.
After the introduction of supersymmetry theory, another situation will arise:
Supersymmetry assumes that all elementary fermions/bosons have their own supersymmetry partners, and the mass of the elementary particle and its supersymmetry partner are strictly equal when supersymmetry is maintained.
And because of the different statistical properties of particles, the Fermi cycle has an extra negative sign compared to the Bose cycle.
Therefore, the radiation correction of the Higgs particle mass by the elementary particles and the contribution of its supersymmetric partner are strictly of equal sign, and the two exactly cancel each other.
in other words.
Supersymmetry protects the Higgs mass from radiation corrections from massive particles, which solves the gauge level problem.
Very simple and easy to understand.
But although supersymmetric particles are perfect in theory, there has always been a problem in the experimental stage:
It has been almost fifty years since supersymmetric particles were proposed, but the physics community still has not found any supersymmetric particles.
This time span even exceeds the proposal to confirmation of the quark model - the quark model was proposed in 1964, and it was confirmed by Mr. Ting Zhaozhong ten years later.
So all the time.
Even Yang Lao, Tehuft and others are not very optimistic about supersymmetric particles or supersymmetric theory.
Of course.
They are not denying the theory itself, but because of the current situation, assuming that supersymmetric particles exist, there is a high probability that they will have to reach an energy level desert or even an order of magnitude higher than a desert to find them.
This is obviously a level that is difficult to achieve in today's physics.
to some extent.
This may be something that only the next generation or even the next generation can witness.
What Mr. Yang said at that time was actually this:
"If you want to be successful and famous, I don't think supersymmetry theory is a suitable direction, because you may not live to experimentally verify the theory."
As a result, according to some marketing accounts, Mr. Yang is opposed to the supersymmetry theory.
That’s not all, there are even more outrageous things.
The setting that Liu used for the framework of the universe in "The Three-Body Problem" is supersymmetry theory, or superstring theory, and then some marketing accounts said that Yang Lao dissed "The Three-Body Problem" as garbage.
It can only be said that a lot of content is very distorted in the process of dissemination.
Another example is what Xu Yun said when he was writing a novel:
"Every order for the serialization period is women's clothing."
Then, under the spread of some hateful trolls, it became [women’s clothing for every order at any stage] → [women’s clothing for every book ordered over ten thousand] → [women’s clothing for high-end orders over ten thousand].
What a pity, the price of that book's haute couture is more than 30,000, okay?
The topic returns to reality.
Not to mention Academician Pan, Xu Yun, and Mr. Yang.
Even Witten himself did not expect that the particles discovered this time would actually be two supersymmetric particles - and they were not suspected, but almost real.
Because it is not difficult to see from the appearance.
The expression derived by Witten carries the fermion operator Q. After the conjugate matrix is changed, the oscillation peak signal of one particle can be perfectly converted into another particle.
At the same time, after removing the influence of the gluon field.
The physical properties of the two particles are also symmetrical - as mentioned before, one of the two particles is a fermion and the other is a boson.
In other words.
This is a two-way fit between physical phenomena and mathematical calculations.
No one can deny that these two particles are supersymmetric in nature when facing this result.
True.
These two supersymmetric particles are not as good as dark matter in terms of individual value or, to put it bluntly, award-winning value.
But in the long run, the value it may derive is higher than that of dark matter.
Because supersymmetric particles are directly linked to it, but what about superstring theory?
Of course.
Supersymmetric particles are only a key piece of evidence for superstring theory, but they cannot be said to prove the authenticity of superstring theory.
Not to mention that if it really reaches that level, the proof is no longer the two supersymmetric particles, but a framework that brings together a large number of supersymmetric particles.
In a sense.
These two supersymmetric particles are like medicinal herbs in traditional Chinese medicine. As for the effect of the prescription, it still depends on the specific combination of medicinal materials.
Think of this.
Xu Yun couldn't help but touch his chin, a hint of understanding flashed in his eyes.
Although supersymmetric particles are precious, they are obviously not worth the value of the second part of the formula.
So what the second part of the formula really involves should be
Superstring theory?
Or to be more precise
The direction of great unification?
Objectively speaking.
The possibility of this kind of speculation is still very high.
Then Xu Yun shifted his gaze a little further and looked at Atsushi Suzuki who was standing aside.
If I remember correctly.
At the press conference of Kamiokande Laboratory, Suzuki Atsushi once used supersymmetric particles as a stunt, but in fact, the particles had nothing to do with supersymmetry.
At that time, Atsushi Suzuki probably could not have imagined that this time the Academy of Sciences would not only discover dark matter, but also supersymmetric particles, right?
Does this count?
Shrimp and pig heart?
Note:
I saw Xu Yun and Xiaomai’s article on some indescribable website. It’s hard to explain in words.
(End of chapter)
