Volume 1: Student Life Chapter 482: The Eve of the Experiment
In the dormitory building of SLAC, Chen Zhou was sitting at the desk, habitually tapping the draft paper with a pen.
Feynman once said, "If in some catastrophe all scientific knowledge were destroyed, and only one sentence were passed on to the next generation, what sentence would contain the most information in the fewest words? I think it would be the atomic hypothesis, that is, all matter is composed of atoms."
People now realize that atoms are composed of atomic nuclei and extranuclear electrons.
The nucleus of an atom is composed of nucleons, namely protons and neutrons.
So are there more microscopic structures inside the nucleus?
The answer given by modern physics is that nucleons are made up of quarks.
Physicists use "flavors" to distinguish different quarks.
As for why "taste" is used instead of other things.
There is a legend that this was when Gell-Mann was eating ice cream while doing scientific research, and he casually used the color and flavor of the ice cream to label physical quantities.
At present, physicists have discovered six different "flavors" of quarks, namely up quark (u), down quark (d), charm quark (c), strange quark (s), top quark (t) and bottom quark (b).
These quarks of different "flavors" also have corresponding antiquarks.
Speaking of which, the existence of up quarks was first proposed in 1964.
Then in 1967, deep inelastic scattering experiments conducted at the SLAC linear accelerator provided the first evidence for the existence of this quark.
As for the unique "flavor" of these quarks, their sum is the flavor of hadrons.
The self-selected parity of hadrons is determined by the spin of quarks and their mutual orbital angular momentum.
Muons can be divided into two major categories according to their different "flavors".
One type is flavor-neutral mesons, which means that the positive and negative quarks are the same.
Just like the up and down quarks of mesons, they are considered to be of the same "flavor."
The other type refers to mesons with the "flavors" of charm quarks, strange quarks, top quarks and bottom quarks, that is, mesons with different "flavors" of positive and negative quarks.
For this kind of meson with "flavor", it can be named according to its different "flavors".
The naming of flavor-neutral mesons is not only based on the "flavor" of the meson, but also on whether the total spin of the quark pair is 0 or 1, and whether the orbital angular momentum is odd or even.
For example, baryons contain three quarks, and they can be distinguished only by different "flavors" of quantum numbers.
Highly excited hadrons are represented by adding an "*" to the corresponding hadron name, and their mass is indicated in brackets after it.
However, strong interactions allow new forms of matter to exist.
What Chen Zhou was chasing with all his might at this moment but was unable to get a full glimpse of was the glue ball composed of pure gluons. This was this new form of matter, also called the strange hadron state.
In addition to glueballs, there are also mixed states composed of quarks and gluons, and multi-quark states composed of more than three quarks, etc., which also belong to this strange hadron state.
Finding and studying these new forms of matter will provide important information about the formation of hadrons from quarks and gluons.
If exotic hadron states do not exist, it would mean that the basic theory of strong interactions requires major changes.
The strong interaction force exists between quarks.
This is the strongest interaction force in nature known to humans.
The strong interaction is transmitted through the gluon field, similar to the electromagnetic force between electric charges being transmitted through the electromagnetic field.
A proton contains three quarks, which form a bound state through strong interactions transmitted by gluons.
Moreover, the mass of the three quarks that make up the proton accounts for less than 2% of the proton's mass. Most of the mass comes from the gluons involved in the strong interaction.
Therefore, it is extremely important to study glueballs composed of pure gluons.
Thinking of this, Chen Zhou's pen suddenly paused, and then he placed it on the draft paper.
Chen Zhou then opened the browser on his computer and began searching for content related to strong interactions.
This is the last difficult problem Chen Zhou has encountered in his current theoretical research on peculiar quantum number glueballs .
He needed a reasonable and sufficient explanation of a difficult problem in the strong interaction before he could finally reach that, perhaps the commanding heights of the content of the glueball theory of strange quantum numbers.
While waiting for the browser page to jump, Chen Zhou glanced at the date and time in the lower right corner of the computer screen.
Today is March 7th, and 7 days have passed since Cross completed the compilation of all the documentation.
There are 24 days left until SLAC closes its collider laboratory.
Chen Zhou originally thought that he had plenty of time, as he had the two days when Kroos performed beyond his expectations as a foundation, but now he feels that time is running out.
It’s not because of anything else, but because of the final difficulty he is facing now.
Originally, Chen Zhou thought that he had solved the problem of the detection method of the colloid ball experiment in his previous research.
Unexpectedly, as the research on the strange quantum number glueballs became more and more in-depth, the originally innovative detection method of the glueball experiment once again ran into the wrong question collection when conducting paper-based experimental research.
When Chen Zhou saw this part, he was completely stunned.
This was an unexpected event that he had not expected.
And this accident cannot be said to be small.
If the problem cannot be solved, all their previous efforts will be in vain.
The final experimental plan that Friedman, Cross and others have been waiting for will come to an end over time.
This is something Chen Zhou cannot allow.
No matter what the final experimental results are, the road of theoretical research must not be interrupted by him before the experiment is carried out.
Otherwise, his heart will be condemned.
Therefore, after discovering this problem, Chen Zhou did not stop for a moment and only thought about how to solve this problem quickly.
But sometimes it is like this, the more you want to solve a problem, the more difficult it becomes to solve.
The difficulty also increases exponentially.
"Strong interaction is contrary to our intuition. Unlike gravity and electromagnetic force, whose strength is inversely proportional to distance, for strong interaction, the closer the distance, the weaker it is, and the farther the distance , the stronger the force..."
Looking at the literature he found, Chen Zhou fell into deep thought again.
What this means, in simple terms, is that when you try to separate the quarks in a proton, the further apart you separate them, the stronger the force you need to pull them apart.
And this force is strong enough to create a new pair of quarks in a vacuum without separating the existing quarks.
Just like a magnet, when you break a magnet you don't get two magnetic monopoles, you create two new magnets.
This property of strong interaction is called "color confinement".
Chen Zhou was trapped in this kind of "sexual confinement".
Shaking his head slightly, Chen Zhou threw away the complicated thoughts in his head.
He reached out and picked up the collection of wrong questions placed aside, and turned to the part about the detection method of the glue ball experiment.
While looking at it, I sorted it out on the draft paper.
He tried to find something different in it, hoping to make a breakthrough from the content itself.
Speaking of which, the problem Chen Zhou is facing now is about the theory of elementary particles.
The theory of elementary particles is essentially still a developing theory.
In many aspects, it is still unsatisfactory.
In the theory of elementary particles, there are two theoretical issues of philosophical significance that remain to be clarified.
One of them is the hierarchy problem.
Another is the issue of interaction and unity.
"Color confinement" belongs to the problem of interaction and unity.
At the atomic level of material structure, the electrons and nuclei in atoms can be separated.
At the nuclear level, the protons and neutrons that make up the nucleus can also be separated from the nucleus.
But when we enter the level of "elementary particles", the situation changes.
This kind of change is called "color confinement".
This is a question that has not yet found a clear answer theoretically.
Although physicists have proposed many theoretical models, the models differ greatly from each other, and it is difficult to verify and judge by experiments which model is correct.
Chen Zhou originally thought that he had avoided this difficult problem that had plagued the physics community for decades and could go straight to the heart of the matter and dig out the glue ball that had been hidden for a long time.
But I didn't expect that on the eve of the experiment, I would still be trapped here.
"Quarks are transferring and exchanging gluons, and at the same time, gluons are emitting and absorbing gluons. This is equivalent to the process of gluons being transferred between quarks, and multiple gluons are 'strongly pulling' on each other..."
As time passed slowly, the amount of draft paper on Chen Zhou's desk increased.
However, the solution to the problem has never been found.
It was already dark outside and it was already 7 o'clock in the evening.
Chen Zhou stared at the draft paper and the collection of wrong questions, but he was not looking at the content on them, and his eyes were not focused.
He slowly put down the pen in his hand and murmured, "The collection of wrong questions is getting thicker and thicker, and I can't find any solution at all..."
At this time, there was a knock on the dormitory door.
Chen Zhou stood up and went to open the door.
You don't need to know that the person knocking on the door must be Cross.
During this period, Cross would knock on the door at this time almost every day, and then call Chen Zhou to drive out to eat together.
Because at this time, the SLAC cafeteria has long run out of food.
Chen Zhou also asked Cross why he didn't come earlier to invite him to have dinner together.
Unexpectedly, Cross explained with a smile: "It's because the food in the SLAC cafeteria is too bad. As long as we can make it through the cafeteria's meal time, Professor Friedman will allow us to go out to eat, and we can also replenish our hugely consumed bodies..."
When the dormitory door opened, as Chen Zhou expected, it was Cross standing at the door.
Cross smiled at Chen Zhou and said, "Let's go out for a meal, some fresh air, and a view of the sea."
Chen Zhou hesitated for a moment and nodded: "Okay, wait for me."
Having said that, Chen Zhou turned and walked into the house, picked up his backpack, and stuffed the collection of wrong answers into it.
This was the first time in so many days that Chen Zhou went out to eat with his backpack.
Coupled with Chen Zhou's obvious hesitation before.
Although Cross was puzzled, he did not ask any more questions.
After all, judging from the research progress during this period, it has been quite smooth.
What Chen Zhou encountered should be something beyond the topic of the jelly ball experiment.
So, Cross put away his curiosity.
After the door was closed, the two walked out of the dormitory building one after the other.
Cross asked casually, "Chen Zhou, the theoretical research on the strange quantum number glueball can probably be completed in these two days, right?"
Chen Zhou nodded subconsciously, but immediately realized something was wrong.
He thought for a moment and said, "If everything goes well, it might only take these two days, or maybe..."
However, before Chen Zhou finished speaking, he heard Cross say, "I told you that at your speed, you can complete the entire theoretical research in two days at most. Professor Friedman also said that it might take more than two days. I even argued with him..."
Chen Zhou listened silently without saying anything.
After a while, Cross remembered that Chen Zhou seemed to have not finished speaking, so he asked: "Didn't you finish what you said just now? You said it's possible, it's possible what?"
Chen Zhou raised his head and looked at Cross, and said in a deep voice: "It may take more than two days."
The happy expression on Cross's face froze instantly. He asked in disbelief, "More than...more than two days?"
Chen Zhou nodded: "Now we have encountered a difficult problem that must be solved. If we can't solve it, we may not be able to catch up with the final experimental plan..."
Cross had never expected what Chen Zhou said.
He suddenly panicked.
Have all the efforts and hard work during this period been in vain?
If we can’t catch up, what about the final experimental plan?
So what about Professor Friedman?
Thinking of Professor Friedman, Cross immediately asked, "What about this situation..."
Before Cross could finish, Chen Zhou said, "I have already reported this situation to Professor Friedman. We are currently adjusting the final experimental plan."
After a pause, Chen Zhou continued, "The deadline is the last three days. If we can solve this problem in the last three days, then we will have enough time. If not, then we will choose the best experimental plan we have."
As soon as Chen Zhou finished speaking, Cross became like an eggplant hit by frost, completely wilted.
Seeing this, Chen Zhou didn't know what to say.
Originally the development trend was positive, but who could have expected that such a big problem would suddenly arise.
The two arrived at the parking lot and walked to the side of the car.
Cross suddenly asked, "What kind of problems did you encounter?"
Chen Zhou replied: "'Sexual confinement'."
Hearing these three words, Cross's expression dimmed again.
This is an unresolved problem in the development of the theory of elementary particles.
The origin and mechanism of "color confinement" are among the most important basic issues in current physics research.
"Alas..." Cross sighed lightly and said unwillingly, "I didn't expect to encounter such a problem on the eve of the experiment. It seems that God wants us to have regrets..."
Chen Zhou didn't know whether God wanted them to have regrets.
Chen Zhou only knew that in the last three days, he would go all out and not leave any regrets for himself.
After dinner, Chen Zhou thought for a while, and then said, "Professor Cross, let's go to the beach to enjoy the breeze..."
Cross glanced at Chen Zhou and nodded slightly.
The car turned and drove towards the seaside in the bay area.
