Before reading this chapter, I suggest you read Chapter 216, the part about the destruction of the world.
...........
"..."
First row.
Listen to these words coming from Witten's mouth.
The scene suddenly fell into a somewhat subtle silence.
Anton Salinger flipped through his stack of reports a few times, pulled out the one with the same number as Witten's, and put it in front of him to examine it carefully.
The other people quickly made the same move.
Another moment passed.
Anton Salinger put down the document, made eye contact with Academician Pan like a master and a disciple, and then said to Witten:
"Mr. Witten, your idea is indeed very innovative, but..."
"With all due respect, there seems to be no charm quark in the physics community at present... No, it should be said that there is no evidence that quarks and gluons will transform..."
Anton Salinger finished.
Many people, including many attendees, nodded at the same time.
Mentioned before.
The so-called hadron.
It refers to the particles that participate in the strong interaction, including Meson and Baryon.
After the quark model is established.
The physics community came up with a method called deep inelastic scattering... which is the DIS method that many people are familiar with to explore the structure of hadrons - at that time, hadrons were mainly protons.
Simply put, it is to bombard protons with high-energy electrons, drive the electrons into the interior of the proton, and infer the internal structure of the proton through the analysis of the final particles.
Therefore, this experiment is also called the electron-proton deep inelastic scattering experiment.
DIS illustrates a very important concept:
The partons within the proton have the property of "asymptotic freedom".
Simply put...
The closer the parts are, the weaker the strong force is.
When part molecules are very close to each other, the strong force is so weak that they can act as free particles.
This phenomenon is called "asymptotic freedom".
On the contrary, the greater the distance between partons, the stronger the strong force.
In 1973.
Across the sea, scientists Gross, Politz, and Wiltzke discovered that the non-Abelian gauge group under the SU(3) color gauge group has the property of asymptotic freedom, thus establishing a theory to describe the strong interaction—that is, Hehe
The famous quantum chromodynamics, and won the Nobel Prize in 2004.
That's right.
Gross—that is David Gross who is sitting opposite Xu Yun now.
There are two basic types of degrees of freedom, or two types of particles, in QCD:
One is quark, fermion, spin 1/2, which is the quark in the quark model.
The other is gluons, with spin 1, and bosons, which are media particles that transmit strong interactions.
That is, quarks form a structure, and gluons glue them into hadrons.
To use a real-life example, quarks are almost like bricks, and gluons are like cement. Both are indispensable.
Among them, quarks have six colors: up, down, top, bottom, strange, and charming.
Gluons have eight states.
But the problem is...
Although both are core substances of the strong nuclear force, there is currently no evidence to prove that there is any connection between the two in terms of conversion.
In other words, quarks are quarks, and gluons are gluons.
There is no way to complete the conversion by adding a meson, lepton, or whatever.
As the world's top...even the number one physicist, Witten cannot possibly not know this.
Facing Anton Salinger's question, Witten looked very calm at the moment, as if he had been prepared for it.
He once again pulled out a document from the report and handed it to Anton Salinger:
"Mr. Salinger, please take a look at this."
Anton Salinger glanced at Witten first, then took the document and started reading it.
After a while.
Anton Salinger suddenly let out a whisper:
"Hey...is this...the baryon number is out of balance? Is the decay width of the coupled up-type quark field so narrow?"
Hear this.
Higgs, who was opposite Anton Salinger, moved the tips of his ears slightly and couldn't help but say:
"Mr. Salinger, what is the report number?"
Anton Salinger glanced at the footer:
"P292."
Higgs quickly read the corresponding report.
Number of baryons.
This is a very core property of baryons. Under normal circumstances, the baryon number of baryons is conserved.
For example, in the b-decay of free neutrons, the baryon number before the reaction is 1, and the baryon number after the reaction is also 1.
The conservation of baryon number is caused by interaction and color confinement. Hadron collision experiments did not find that color confinement was destroyed, so there is only one theoretical possibility for baryon number imbalance:
A new canonical group has been added.
That’s right!
Students with good memories should remember it.
As mentioned in paragraph 35 of Chapter 463, the report discovered by Xu Yun showed that the property framework of particles is a non-pure gauge theory!
That is to say...
The color space of quarks is directly summed with the weak isospin space.
Think of this.
Higgs suddenly realized something, took a breath, turned to Xu Yun and asked:
"Dr. Xu, can you please find out the matrix element canonical group calculation formula you calculated before?"
Xu Yun was a little surprised by Higgs's words, but he quickly nodded affirmatively:
"no problem."
After saying that, he came to his original position, quickly flipped through the pile of documents a few times, and pulled out a somewhat messy piece of manuscript paper.
Then he walked to Higgs with the manuscript paper, scratched his head a little embarrassedly while handing it over, and said:
"Mr. Higgs, this is the canonical group expression. The process is a bit sloppy. Please bear with me."
Xu Yun's words are not "self-effacing". This calculation is indeed quite sloppy.
After all, the previous calculation time was very tight, and the content written by Xu Yun must have been mainly simplified. I never expected that Higgs would use this thing.
Fortunately, Xu Yun's handwriting is still three-dimensional. Although it looks a bit messy, it does not particularly affect the look and feel.
Then Higgs thanked him, took the manuscript paper and read it.
"There are 24 generators...8 gluons, 3 weak interaction bosons, and 1 photon. The standard model occupies 12 of them, and the remaining 12 are the newly introduced weak interactions...
..."
"Three of the deviant field bands, each with a 4/3 element charge, couple the down-type quark field -1/3 and the charged lepton field with a -1 element charge, realizing the mutual transformation of down-type quarks and charged leptons.
.....”
"The coupled up-type quarks carry a 2/3 charge to achieve mutual annihilation of up-type quarks."
"Correspondingly, there are three anti-gain fields, which couple the anti-particles of the above process to realize their anti-particle reactions..."
Higgs was doing calculations while reading, and from time to time he would take the Witten document and check the parameters.
ten minutes later.
Higgs looked at the results he calculated and looked up at Witten with a complicated expression:
"..."
it is more than words.
As we all know.
Different from the U(1) gauge field of photons, gluons originate from the color gauge group of SU(3).
This results in gluons having self-interactions - such as three-gluon vertices and so on.
At the same time, when the quark flavor number is less than 33/2, the b function in QCD is greater than 0, resulting in the phenomenon of asymptotic freedom.
in this case.
Once the color space of quarks and the weak isospin space are directly summed, a phenomenon may occur:
Charm quark pairs have a probability of annihilating into gluons (referenced from Weinberg's "Dream of the Ultimate Theory" and Graheory, of course, it is almost impossible to happen in reality, and I ignored the axial flow anomaly)
In other words.
Whether it is a mathematical matrix or a detection result - that is, a physical phenomenon, they all fit in with Witten's ideas at this time.
Or to be more precise.
This is the only idea that applies to both ends.
Of course.
This has nothing to do with the discovery of a structure smaller than a quark. It is a new quark decay state that is highly suspected to be real.
Simple quark decay is not uncommon.
For example, the most typical example is that after the up quark releases a positron and neutrino, it decays into the down quark.
It's just that what Witten and the others have discovered now is not the conversion between quarks, but the transformation process between quarks and other basic particles.
From a purely model perspective, quarks are still the smallest particles in existence.
Then very quickly, Nima on the side raised his hand again:
"Mr. Witten, there is no problem with this idea mathematically, and the phenomenon also supports its establishment, but..."
"The probability of successful annihilation seems too low, even lower than one in 13.7 billion of the generation of double charm quark particles. It is simply unimaginable..."
When Xu Yun on the side heard this, a strange emotion appeared in his heart, and he couldn't help but ask:
"Mr. Nima, what is the probability that charm quarks annihilate into gluons?"
Nima glanced at him and turned her manuscript paper towards him:
"One in 85.8 billion, a dicharm quark particle can be divided into two pairs of quarks, which means that it takes 42.9 billion dicharm quarks to pay their 'lives' before one can be converted into a gluon."
"If Double Charm Quark had life, maybe she would definitely refuse this method of committing suicide."
"After all, if the conversion fails, her ending will be the annihilation of quarks into photons, and she will disappear forever."
"That's not necessarily the case."
Xu Yun subconsciously retorted. After coming back to his senses, although he felt that saying this might be a bit rude, he still said:
"Perhaps the dicharm quark particles were already prepared before their annihilation, determined to pay all costs and become gluons no matter what."
Nima's brows suddenly raised when he heard this. Now in his forties, he is still less stable than other elders:
"Oh? This is quite an interesting statement. So Dr. Xu, why do you think bicharmed quark particles must turn into gluons?"
Xu Yun thought for a while and guessed:
"Maybe... maybe the particle she likes is gluon?"
"After all, the degrees of freedom of the strong interaction are quarks and gluons. If particles are alive, it is not impossible for quarks and gluons to fall in love."
Looking at Xu Yun with a serious look on his face, he opened his mouth but finally said nothing.
Although his reason told him that this kind of thing was almost impossible to be true.
But when he saw the probability he calculated, he stopped thinking about refuting it.
after all.....
This is a phenomenon that occurs only after 42.9 billion impacts.
Even if it has nothing to do with love, it still should not be ridiculed or denied.
Xu Yun's words made the atmosphere at the scene feel a little depressed, but soon, Witten spoke again:
"Okay, everyone, in short, we have now successfully deciphered the reason why these two particles maintain such an attitude."
"Whether these two particles are related to love or not, this is something worth celebrating, isn't it?"
Only then did everyone come back to their senses and applauded one after another.
As Witten said.
As this mechanism is proven, the ‘state’ of these two particles becomes clear:
The dicharm quark is split into two particles, and the two particles they form have the same properties. According to the principle of quantum chromodynamics, they should repel each other.
But the strengthened gluons formed a more stable and powerful chain, tightly imprisoning the two particles together, as if holding each other's hands, neither one was separated.
No wonder Xu Yun would say this is love...
all in all.
After solving this problem.
The next link...or the only link left is...
How about analyzing the specific structure of particles?
Is it a diquark particle?
Or three quarks?
Or four quarks or five quarks?
This judgment is not difficult, after all, all the necessary parameters are already available.
Although the current understanding of quarks in the physics world is still relatively limited, it is still relatively easy to determine the composition of a particle.
Now after determining the ‘state’ of the two particles.
As long as a gluon field and other parameters are introduced, the specific structure of the particle can be analyzed.
But after a few minutes of calculation.
Wei Teng suddenly shrank and stared at the manuscript paper in his hand:
"This...this is..."
...
Note:
The PCT index is a bit high. The doctor doesn’t let me go home at night to code. I estimate that I can only maintain attendance at 4,000 for the past two days. It’s hard to support it. Also, don’t mention the suggestion of asking for leave. I remember explaining the reason before.
