Finally, Academician Tang was called over by Guo Ding.
After arriving at the computer room, he asked with a smile, "Did Xiao Yi encounter any problems?"
"Uh..." Guo Ding nodded. "That's true."
What Xiao Yi asked is indeed a problem, right?
It's just... it's just a little bit over the top.
When he saw Tang Yifang, Xiao Yi once again took out the results he had just calculated and explained them.
After Tang Yifang listened, he was as stunned as Guo Ding was just now.
After hesitating for a while, he said, "In other words, do you think there is a big error in the W boson mass predicted by Standard Model?"
Xiao Yi nodded. "That's probably it."
"According to my calculations... it is at least more than 5 standard deviations."
"Five standard deviations?" Tang Yifang was startled again, then he stretched out his hand and said, "Let me see your calculation process."
Xiao Yi nodded, and then handed Tang Yifang the scratch paper he used for calculation just now.
Tang Yifang started to read.
For High Energy Physics, there is a criterion called the 5σ criterion, which is widely considered to be the standard for judging whether the results are statistically significant. Among them, "σ" refers to the standard deviation in the normal distribution curve, indicating the degree of data deviation from the mean.
For experiments whose results reach 5σ, it means that the results of this experiment are very likely not due to statistical fluctuations or systematic errors, and are very likely to be caused by new physical phenomena that have not been discovered in a certain system.
This means... Xiao Yi may have discovered something that can subvert the world of physics!
Maybe even... maybe new physics!
But how is this possible?!
Tang Yifang had the same idea as Guo Ding.
Are you kidding me?
With disbelief, Tang Yifang began to look at Xiao Yi's calculation process from beginning to end.
And soon, he squinted his eyes and discovered the problem.
"Wait... what method of handling errors are you using?"
"No... the Error Handling Method you are using is completely different from the processing of W boson data by other research institutes."
"In addition, you also need to explain the statistical methods you used and how you finally obtained these results."
He turned to look at Xiao Yi and asked, "If you can't explain the principles of these methods, you won't be able to convince the vast majority of people."
He thought he had found the key point of the problem, and he felt relieved.
That is to say, how could there be a problem on W boson mass?
What's more, even if a problem does occur, how could it be discovered by Xiao Yi by just counting a few moves?
However, after hearing Tang Yifang's question, Xiao Yi asked doubtfully, "Hasn't the High Energy Physics world ever used my method?"
"As for this method, it should be quite easy to think of, right?"
Xiao Yi's rhetorical question was immediately dismissed by Tang Yifang.
What?
Is this method easy to think of?
Xiao Yi also continued to explain at this time, "The first and most critical method is Maximum Likelihood Estimation, in which I introduced an improved algorithm that can process high-dimensional data more effectively and ensure the accuracy of the results."
While talking, he pointed at the scratch paper and explained to Tang Yifang how he came up with these new methods.
"Then there is Bayesian Estimation. You see here, I introduced another simpler prior distribution model, which makes the calculation of posterior distribution more efficient and accurate. At the same time, I also used Markov Chain Monte Carlo method. This method I used in the Absolute Electronic Computation principle, and now I have also added it to the processing of these experimental data."
"Of course, these are just some minor improvements in statistical methods. As well as the Error Handling Method you just mentioned, I mainly established an analysis framework here. This may be the key reason why you are unclear about this method."
"You see, here we first introduce an error matrix and represent all possible error sources as elements in the matrix. For these errors, we also need to divide them into controllable errors and uncontrollable errors. Controllable errors are those that can be reduced through further calibration and experimental design, while uncontrollable errors are caused by natural randomness or external environmental factors."
"Then it is matrix decomposed. Here I mainly use two methods. The first is Singular Value Decomposition. By decomposing complex error sources into a set of independent components, the main error contributing factors can be identified and the impact of each factor can be quantified."
"In addition, there is a Principal Component Analysis that can help us find the most significant error patterns in high-dimensional data."
"And then there's..."
In this way, Xiao Yi explained his data processing method to Tang Yifang from beginning to end.
Tang Yifang thinks that his mathematics is pretty good. Although he is still a little worse than those pure mathematicians, he is still very good among physicists.
However, now facing Xiao Yi, a very information-intensive method, he still became confused.
"... Of course, these results are limited to my paper calculations today, and my energy is limited. If more relevant experimental data can be extracted and processed uniformly, I think the accuracy can be improved a lot."
After saying that, Xiao Yi felt a little dry in the mouth. He looked around to see if there was any place to drink water. But at this time, Guo Ding appeared out of nowhere and handed him a glass of water. "Boss, please drink water."
"Uh..."
Xiao Yi glanced at him speechlessly, but there was no nonsense. He took the water and took a swig, which slightly relieved the dryness in his throat.
Next to him, Tang Yifang was still staring at the draft paper, and his mind was still reviewing the explanations given by Xiao Yi just now.
Until finally, he turned his head carefully and said to Xiao Yi, "Can you say it again?"
Xiao Yi: "... Okay."
So he repeated the methods he used again. Of course, he spoke more slowly this time. After all, he still had to take care of the elderly.
But this time, Tang Yifang finally understood the principle of this method.
Although there are still some parts that he doesn't understand, there are some processes that even he finds a bit wonderful.
"So, how did you come up with this method?" Tang Yifang couldn't help but ask, "This method... have you thought of it before?"
"Well..." Xiao Yi said, "When I was processing the data today, I thought about it and felt that using some common methods to process this type of data might be a little inaccurate. Then I thought about it and felt that it would be better to use this method to process the data in this particle accelerator."
After saying that, he noticed that Tang Yifang and Guo Ding in front of him both looked like they had eaten something.
After hesitating for a moment, he quickly made up for it. "Uh... maybe it has something to do with before? The Absolute Electronic Computation I worked on before was originally because I participated in a two-dimensional materials research group, and there were also experimental errors..."
Tang Yifang took a deep breath and finally said, "Okay, don't say any more."
"In this way, I will arrange a report for you, and you will introduce your method. After that, I will start organizing researchers to recalculate the mass of W boson based on the method you proposed."
"Finally." Tang Yifang suddenly became solemn again. "If we can really produce a significant result, I would like to express my gratitude to you on behalf of Institute of High Energy Physics."
Hearing Tang Yifang's serious statement, Xiao Yi was stunned for a moment, and then solemnly responded, "Okay!"
Tang Yifang nodded to him and was about to leave. However, when he just walked to the door, he remembered something again and turned around and said, "By the way, I will arrange your report in 10 days. In addition, there will be a researcher from CERN next week. The research team came to us to exchange and learn, and the person leading the team is named George Parisi. If your method can convince him, maybe we can give you more experimental data from the LHC, and those data should be more accurate than our BEPC data."
CERN research team?
Xiao Yi was stunned again.
CERN is European Organization for Nuclear Research, and the world's largest particle accelerator is also the largest technological creation on the planet, Large Hadron Collider LHC, which was built with funds prepared by this organization.
It would be an understatement to call it a spectacle.
Comparing the LHC and BEPC, the former has a circumference of about 27 kilometers, while the latter has a circumference of only 240 meters. From this, we can know how "large" this Large Hadron Collider is.
I just didn't expect that I happened to meet the research team from CERN.
This is a normal thing. Academic exchanges are a common thing, not to mention in the field of high-energy physics. Research teams from different Institute of High Energy Physics often go to each other.
Of course, due to the status of the LHC, it is more likely that teams from other places will try their luck at CERN.
Xiao Yi nodded and said, "I understand."
Tang Yifang smiled and nodded, then left.
Of course, Guo Ding is still here to stay.
At this time, he was quite surprised and said, "Professor George Parisi is actually here. This is really rare."
Xiao Yi asked doubtfully, "Do you know this professor?"
"Of course, this person is considered a super expert in Theoretical Physics." Guo Ding said, "Whether it is Quantum Field Theory, Statistical Mechanics or whatever, he is very proficient. The same is true for High Energy Physics. He developed a probabilistic field theory framework for the dynamics of quarks and gluons, which can be regarded as providing guidance for our project."
"All in all, he is a genius who knows everything." After a moment of pause, Guo Ding glanced at Xiao Yi and said, "Just like you."
Xiao Yi waved his hand and said modestly, "No, no."
Guo Ding rolled his eyes.
Still being so modest.
Thinking of what Xiao Yi just put forward, if it is true, it will really cast a dark cloud on the building of physics.
But... what Theoretical Physics likes most now is this kind of dark cloud.
Finally, he said, "No matter what, I wish you success. If you need any help in the next few days, just ask me."
"Okay!" Xiao Yi nodded.
The room fell silent and returned to thinking.
Xiao Yi looked at his scratch paper again.
"Well... there should be some areas that can be optimized, and there are also things worth optimizing in the algorithm."
These are trivial matters for Xiao Yi. There are still 10 days left, which is enough for him to polish this method.
However, another question still arose in his mind at this time.
"The question is... these collision data are derived from heavy ion collision experiments. The purpose is to study QGP under strong interaction force, but they can show that W boson is overweight. Is there any correlation?"
His eyes turned to the experimental data, and his eyes seemed to become deeper and deeper while thinking, as if he could see the microscopic world through the twists and turns of the lines, the scattered points, the twists and turns of the coordinate system, and the densely packed data.
Suddenly, something he mentioned when chatting with Guo Ding appeared in the center of his mind.
Mass gap problem for the Yang-Mills equation.
The mass gap problem is something that still cannot be explained in the strong interaction force.
W boson involves weak interaction forces, and now W boson has an overweight mass...
Is there a connection between the two?
Of course, in a certain sense, the two are absolutely related. After all, if these two basic forces can be unified, a way to connect them must be found.
Even if the two have not been unified yet, in terms of the dialectical materialist philosophy, there is a universal connection between all things.
Applying it to the two, one can naturally draw the conclusion that there is a correlation between the two.
However, it would not be in line with the scientific outlook to simply draw conclusions from a philosophical sentence.
Therefore, we still have to prove this through scientific methods.
"Is it necessary to solve the problem of mass gap?"
He couldn't help but think of this in his mind.
This is one of Millennium Prize Problems.
Are you really worried about this issue?
In the end, he shook his head and said, "Forget it, let's first determine whether W boson mass is really overweight."
At present, he has only reached this conclusion through no more than 100 signal event data. For High Energy Physics, the amount of data is completely insufficient.
If it is just some ordinary discoveries, perhaps a few thousand data volumes are enough, but if it is an important discovery, millions of signal events may be needed to ensure high statistical significance.
In order to discover Higgs Boson, the LHC counted a data volume of 5fb^(-1).
fb^(-1) is a unit, which is translated as an inverse flying target. 5fb^(-1) means that in an experiment, 5x10^15 collision events occurred per square femtometer of effective area.
It is enough to see how huge the amount of data is.
Therefore, for the W boson overweight event, such a large amount of data may not be needed, but it will not be less anyway.
Only in this way can the final result convince people.
"So, I'm still busy."
However, Xiao Yi is already looking forward to these activities.
For him, the question [whether W boson is overweight] has aroused a very deep interest in him.