Chapter 462: Some casual words clear up doubts~(8.4K)
Students who have done particle collision experiments should all know this.
When you enter the laboratory on your first day, your instructor will definitely tell you this:
"In the field of particle physics, a single case report has no reference value."
be honest.
This sentence does apply to most situations, and an isolated example does not make any sense in many cases.
However, in a few cases, it may not be accurate.
The most representative one is the impact experiment conducted by Makoto Kobayashi and others. Everything is 0, and the curve is so flat that it can no longer be flat.
Even if there is only one case statistics, it is enough to explain many problems.
Another example...
At this moment, in front of Xu Yun and others, is this case list numbered.
The protrusions on this list of examples are extremely astonishing. They are as good as the small umbrellas that readers have when they wake up in the morning, and they are about 20 centimeters away.
Don't talk about people in the industry.
Even Chen Shanshan and the audience watching the live broadcast outside the venue can see that this signal is definitely not an accident.
In other words...
Among the magnitudes calculated by the Academy of Sciences team, there is indeed an unknown particle.
However, as a senior fan of AC Milan, Academician Pan knows one thing very well.
That is, until the real hammer comes down, you must endure not to open the champagne no matter what.
After all, let’s not talk about the far side, let’s talk about the near side:
The particles calculated by Atsushi Suzuki and others to be 11.4514gev are capable of overturning the car.
So Academician Pan calmed down, forced himself to calm down, and said to the somewhat excited Carlo Rubbia:
"Mr. Rubia, please calm down. What we need to do now is to collect and summarize the cases first, completely summarize the relevant attributes of the particles and determine the true attributes of the particles. ...
"We can't let the old thing of 750gev happen again."
750gev.
The second half of Academician Pan's words hit Carlo Rubbia's heart like a book of Boruto, causing his whole body to tremble.
The excitement that originally appeared has also subsided by most of it.
Theoretical physicists were all cursing the original operation, but at the time they actually thought they had discovered a new particle, and internally it was said that they had even thought of a name for the particle.
Who would have expected that such a stable particle would overturn the car, and even now it is scolded and still not forgiven.
So after hearing what Academician Pan said, Carlo Rubbia immediately calmed down.
Then he thought for a moment, took out his cell phone, and dialed a number.
After a while.
The call is connected.
"Hello, Mr. Rubia."
Carlo Rubbia moved the phone away and pressed the speakerphone button at the same time:
"Pop, how many cases are there now?"
There was a little tapping sound on the keyboard from the other end of the phone:
"There are more than 2.33 billion messy cases - including meaningless cases."
Carlo Rubbia nodded.
The number of cases reported by my assistant sounds scary, but it is actually quite normal.
Just like two high-speed cars accidentally collided together, if even a few millimeters of fragments were counted, then there would be hundreds, thousands, or even more.
These examples are true to their meaning, and many of them are meaningless and worthless fragments.
Then Carlo Rubbia paused and continued:
“How many cases are there after optimization?”
"8.79 million copies."
"What about the one with the same ups and downs signal?"
"There were 219 major incidents and 548 signal bulges."
Carlo Rubbia's breathing suddenly accelerated a bit.
Different from meaningless cases.
The so-called big event does not refer to the sputtering of various small particles after the collision, but the initial event of the collision of two lead ions.
To use the head-on collision example above, it is the collision of two cars.
Under normal circumstances.
During a large collision, the total number of colliding particles emitted is about 10 to the 14th power.
Among them, the 'big cases'...that is, the total number of 'car accidents' in which collisions occurred, are probably between 2 million and 5 million times - of course, this number varies from project to project. It can only be said that this is a relatively common occurrence.
interval.
Among large events of this magnitude, the number of abnormally large events that can prove the existence of a certain particle is generally...
Starting around 40.
That is to say, among 2 million collisions, 40 major events can show fluctuation signals, which can basically determine the existence of this particle.
By the way.
The number of large cases that originally proved the so-called 750gev particles was...
Two servings.
Then Carlo Rubbia glanced at Academician Pan beside him, and the two nodded at the same time with great understanding.
Just listen to Carlo Rubbia say to the phone again:
"Pop, please immediately transmit those 219 major cases to the information backend of the Chinese Academy of Sciences as quickly as possible!"
"I understand, Mr. Rubia!"
After hanging up the phone.
Carlo Rubbia put his cell phone back into his pocket, took off his eyes, and said to Academician Pan in a serious voice:
"Pan, the rest will be left to you."
Academician Pan nodded towards him, turned his ear back again extremely ably, and ordered:
"Xiao Chen, get ready and enter the information packet into the background as soon as possible!"
"clear!"
After saying these words.
Academician Pan returned to the front row with Hou Xingyuan and Carlo Rubbia.
He first left Suzuki Atsushi, who was gasping for breath, and then said hello to Mr. Yang and Witten, who looked expectant.
Then I waited with peace of mind.
Another moment passed.
Academician Pan heard a reply:
"Academician Pan, all the information has been entered!"
Academician Pan snorted, walked behind Xu Yun, used Xu Yun as a tool to block everyone's sight, and asked in a low voice:
"How's it going? Has the report been verified?"
"Yes, we used the supercomputer Dawn to conduct an emergency analysis. Although the specific properties require subsequent analysis, we can be sure that this is a new particle and not a statistical fluctuation like that."
When Academician Pan heard this, he immediately felt certain.
That last sentence is enough.
Then he thanked Erhui across from him, patted Xu Yun's shoulders hard several times, and strode towards...
Podium.
See this situation.
The atmosphere at the scene, which was already somewhat solemn, became solemn again.
nervous...
expect...
happy...
disgust...
Dumbly...
All eyes were focused on Academician Pan at the same time.
After arriving at the podium.
Academician Pan first calibrated the microphone, looked around, and then spoke slowly and clearly:
"Dear colleagues at the scene, media guests, and friends from the outside world, everyone...have been waiting for a long time."
"Not long ago, the backstage of the Academy of Sciences has received first-hand reports on a total of 219 major cases from relevant parties."
"Of course, the first thing to emphasize is that we don't know whether these 219 major incidents can prove the existence of those particles."
"Maybe there is, maybe there is not, no one can know the truth."
Hear this.
Xu Yun in the audience couldn't help but glance at Academician Pan, who had a look on his face that said, "We really don't know anything."
"..."
As expected of my rabbit...
Then Academician Pan paused and continued:
"Next, our backend staff will synchronize these 219 major incident reports to the data terminals in front of you, and professionals will conduct report analysis and judgment."
"Attendees whose main major is particle physics will receive an additional voting qualification."
"That is, if you think these reports are sufficient to prove the existence of particles, please vote 'yes', if not, please vote 'no' - of course, you can also choose to abstain."
"As for participants who are not majoring in particle physics, they are not eligible to vote, but they can still check the analysis case reports at will."
As soon as Academician Pan said this.
The audience was only silent for a few seconds before a low-pitched discussion broke out.
Many scholars who were a little tired quickly sat up straight, and some quickly flipped through their briefcases to find paper and pens.
Academician Pan's words directly touched their hearts.
After all, as the top bosses in the industry, they have been watching the show in the audience for so long. It is impossible for them not to feel itchy.
But the problem is that the previous process of calculating particle Fermi surface data was very difficult, and even Higgs and others needed assistants to help.
Although these elders at the table were moved, they were really powerless.
But it's different now.
Facing the generated data, they do not need to perform large-scale calculations. What is tested is their long-term ability to analyze the data.
This is their strength, just like riding a bicycle, and they may never forget it in their lifetime.
Of course.
Some people are eager to try it, while others are naturally dissatisfied with the Academy's approach.
"Why?"
On the seat in the tenth row.
Christine was putting her hands on her hips and looking angrily at Academician Pan on the stage:
"Why do you have to do particle physics to have the right to vote? Is this discriminating against cosmology and statistical physics?!"
Lu Chaoyang beside her smiled and explained:
"Ms. Christine, after all, this vote is of great importance. Statistical physics is different from particle physics in this situation."
"Although your knowledge of particle physics is equally profound, not everyone is the same as you..."
Lu Chaoyang's words were not entirely complimentary.
During the previous particle calculation process, he discovered that this girl was indeed an all-rounder and had deep research in particle physics.
However, the current occasion is obviously not suitable to give Christine the green light alone, so I can only feel a little aggrieved to this filial daughter.
As an assistant researcher at Harvard University, it was naturally not difficult for Christine to understand this truth, so she simply complained:
"Forget it, I hope I can have a chance in the future. Why are the documents from your academy of sciences being uploaded so slowly...Huh? Here they are!"
The words just fell.
A file icon instantly appeared on the data terminal in front of Christine and Lu Chaoyang that was originally watching the live broadcast.
Seeing this, Christine couldn't wait to sit back in her seat and quickly clicked on the file.
Although for a scientific researcher, there are more opportunities to come into contact with paper reports on weekdays.
However, computer equipment is very popular these days, and many experimental data are directly viewed on the computer, so it is not difficult to adapt to the current data terminals.
Then very quickly.
Kristine put on the noise-cancelling earmuffs and began to check the relevant data.
[Particle Detection Report] This word may be a bit unpopular in 2023. You can basically see this thing in any black technology article.
But I’m afraid very few people know what the content of such a report is and how to read it.
For example, a very simple question.
At present, all particles are invisible to the naked eye, and their trajectories can only be simulated afterward through a cloud chamber. So how do physicists know what particles they have captured?
Is it an image?
Or some kind of probe test?
no.
The answer is the reported value.
For example, the simplest numerical value is the intrinsic property of the particle:
Mass, charge, spin.
On the basis of the above three, the report will also add a special column:
cp properties.
In addition, data such as the cross section of the generation channel and the branch ratio of the decay channel can be refined through interaction.
Take the Higgs particle discovered in 2012 as an example.
The Higgs particle predicted by the standard model is neutral, with spin 0 and cp
particle of.
It interacts directly with w, z particles and fermions with mass, and the intensity of the interaction is proportional to the mass of the particle.
And it can be seen in the original report.
They found the Higgs particle from a two-photon final state, which means that the new particle can decay into two photons.
Students who have taken junior high school physics should all know this:
Photons have no charge.
Therefore, we know from conservation of charge that the particle is also uncharged.
This chapter is not finished yet, please click on the next page to continue reading the exciting content! In addition.
Since the final state is two bosons, we can also know that the new particle must be a boson.
Then according to the conclusion of the Landau-Young theorem, it can be seen that a particle with spin 1 cannot decay into two photons.
Therefore, the spin of the new particle can only be 0, 2, 3….
Next, we measured the cross-section and angular distribution of the new particles decaying to ww, zz and made a fitting. We found that everything is consistent with [cp with spin 0]
particle] fits well.
Finally, we measured the final states of new particles to bb, mumu, and tautau, as well as the joint production of new particles and tt, and found that they were also in good agreement with the assumptions of the standard model.
Therefore we can draw the conclusion:
This new particle is the Higgs particle.
This is the real basis for determining which model a particle can benchmark against.
Useless knowledge has increased.jpg.
So at this time, these experts are comparing their knowledge of particle models, not other abilities such as computing power.
"Spin 1/2... This is the same value as previously calculated by Professor Witten and others. It satisfies the Pauli Exclusion Principle and is a standard energy localized field configuration..."
"The ll3 process has the largest cross-section and is consistent with the fourth-order Feynman diagram oscillation..."
"Quack, quack, quack..."
The results were watched.
Lu Chaoyang suddenly frowned.
His eyes rested on a numbered report, with a trace of doubt in his eyes.
】
This is a large-scale band signal data chart, recording a small bulge in the final state of tautau gamma.
There are hundreds of similar bulges in the entire report - as mentioned before, it is rare to conduct such a high-level experiment, and a variety of data must be collected.
But this current bulge...
But it's a little strange.
As we all know.
In quantum theory, Hilbert space can be decomposed into the direct sum of Bose state and Fermi state subspaces:
h=h
h?.
If the fermion parity operator is defined as (?1)f, and f is the number of fermions, this is its invariant subspace decomposition.
The eigenvalue 1 corresponds to the Bose state, and the eigenvalue ?1 corresponds to the Fermi state.
The spin of Pluto particles is 1/2, which means that they are fermions.
But now the eigenvalue of this small bulge in the final state of tautau gamma is 1.
This is a little strange...
And just when Lu Chaoyang frowned and thought.
Suddenly there was a whisper in his ear - due to personal habits, he did not wear earmuffs:
"Hey, what's going on with this data?"
Lu Chaoyang subconsciously turned his head and found that Kristen was holding a pen in her mouth, frowning and staring at the screen in front of her.
Seeing Lu Chaoyang looking towards her, the girl turned the screen towards Lu Chaoyang:
"Hey, Lu, come and take a look at this."
Lu Chaoyang poked his head towards her.
She discovered that the report on her screen was not the same one she was looking at, but a numbered document.
As a result, after just two glances, Lu Chaoyang couldn't help but raise his eyebrows:
"This is......"
It was completely different from the content of the report in his hand.
The eigenvalues of the report in Christine's hands are normal, but it is an expression of a scalar field!
Mentioned before.
Scalar fields cannot describe fermions, only spinor fields can describe the spin of fermions. (See Chapter 455)
This is very strange...
Then Lu Chaoyang thought for a while and handed his data terminal to Christine:
"Ms. Christine, to tell you the truth, I also found an anomaly report here."
Christine raised her head and looked at him, then took the terminal and started looking at it.
After a while.
Kristine's voice sounded in Lu Chaoyang's ears again, but this time, this carefree girl's tone was unusually nervous:
"Lu, do you still remember your previous guess?"
Lu Chaoyang was stunned for a moment.
After a few seconds.
He suddenly thought of something and tapped the math paper on the table with his index finger:
"Are you talking about the Riddler before... ahem, the theoretical model that can be established in the 1tev interval?"
Kristine nodded heavily:
"Yes, if that theory is applied, there seems to be room for explanation of this phenomenon..."
Lu Chaoyang's expression changed for a while. He lowered his head and read the report several times, and finally frowned and sighed:
"...It seems that it's not enough. The energy scale is still a little off. No, I should say it's a lot off."
"For that theoretical model to be able to explain this phenomenon, other new evidence is needed."
"Otherwise...the elders here have already expressed their opinions - do you think you and I are the only smart people?"
After hearing this, Christine opened the calculation paper from earlier again, picked up a pen and calculated on it for a while, and then said quietly:
"Indeed, the difference is at least two orders of magnitude."
Just as Lu Chaoyang said.
There are not a few scholars who have discovered this kind of anomaly. After all, there were thousands of people present, including twenty Nobel laureates.
Perhaps no one will be able to completely figure out the causes and consequences of the data anomaly for a while, but it is definitely not just one or two people who discover the anomaly and come up with ideas.
Of course.
There are also some scholars who have not considered it so deeply.
After confirming that the data was normal, someone quickly pressed the voting button representing the existence of particles.
First row.
Looking at the progress bar showing 14 confirmed votes and 0 opposed votes displayed on the screen, Academician Pan’s expression still looked very uncertain.
After all, in this situation, there is no point in criticizing someone and refusing to admit it. On the contrary, it will affect your reputation.
At this moment.
What Academician Pan, Witten and others really care about are the problems shown in a few reports.
After all, the process of proving whether a particle exists is very complicated. It does not mean that it is just a matter of making sure it is captured.
The spin and cp properties of the particles, what kind of particles they belong to, and what their constituent states are... these all need to be explored.
This chapter is not over, please click on the next page to continue reading! "It's strange..."
Witten crossed his left hand across his chest, put his right thumb on his chin, and frowned:
"We have received 39 pieces of abnormal data. Although it has no impact on the conclusion that the particles exist, this abnormal situation cannot be ignored."
"What exactly is going on..."
Beside him, Academician Pan, Zhou Shaoping and Mr. Yang also looked a little confused at this time.
Due to the real-time transmission of signals, the supercomputing background of the Academy of Science and Technology could only prioritize the big issue of verifying the existence of particles. As for small anomalies such as bulges, it was definitely not possible to cover everything.
So even Academician Pan and Hou Xingyuan...or even the person in charge of the company, Carlo Rubbia, were not aware of this situation in advance.
After a while.
Hutft's eyes moved slightly, he slowly raised his hand and said:
"Everyone, I have an idea. Could this particle be similar to the x17 particle? I mean a model rather than an example."
Witten was stunned:
"x17 particles?"
x17 particles.
This is a very topical particle.
This is an example announced by the atomki project team of the Hungarian Academy of Sciences a few years ago.
At that time, they claimed that the new particles discovered during the transition of helium atoms and the decay of beryllium-8 had properties close to a type of predicted boson.
As we all know.
New bosons represent new interactions, so many articles at that time hyped up the possibility that humans had discovered a fifth force.
But actually.
In subsequent verifications by multiple parties, no institution has reproduced this phenomenon.
At the same time, the atomki project team has announced many shocking "major discoveries" before.
For example, in 2001 they claimed to have discovered a new particle of 9ev, in 2005 they claimed to have discovered the abnormal behavior of multiple particles caused by the new particle, in 2008 they claimed to have discovered a new particle of 12ev megaelectronvolts, etc...
However, none of the above discoveries have been repeated for a second time.
Therefore, the atomki project team is also jokingly called the Internet celebrity project team in the industry.
But on the other hand.
Although the case of the x17 particle is probably false, its model is still relatively useful for reference.
Its manifestation is the excited state of the electron even element, and its mass is between the ground state of the electron even element and the π0 meson.
Theoretically, when the electron momentum of the electron element reaches a certain mutation state, it may indeed cause some abnormal data.
But soon.
Higgs, who had studied particle models the most at the scene, shook his head:
"It's unlikely, Gerald. If it's a similar principle to the x17 particle, then it must decay first to produce a positron-electron pair."
"And if positrons are generated, then some signs must be seen in the 1.022mev range, but unfortunately..."
As he spoke, Higgs pointed to a blank space in the report:
"There is no positron-generated signal here."
Tehuft stepped forward and looked at it for a while, then nodded silently.
Higgs is right.
That is to say...
The x17 particle model is not applicable to the current situation.
So what is this exception?
Just when the atmosphere at the scene was a little gloomy.
A voice suddenly sounded in Higgs's ears:
"Ah, hey...it's so weird."
........
Note:
The doctor asked me to be hospitalized, which was hard to bear, but actually I felt fine...
