Chapter 548: Dig and dig in the small base and bury big seeds to steal other peoples homes!
"...."
Looking at Ye Duzheng who looked like he had been waiting for a long time.
Xu Yun was just slightly startled, then nodded quickly and said:
"Okay, Director Ye has given instructions, how dare I, a little soldier, disobey him?"
Hearing this, Ye Duzheng waved his hands quickly:
"Hey, Comrade Han Li, you are joking."
Then he looked around, pointed to a stone table under the shade of a tree, and said:
"Comrade Han Li, why don't we go there and have a chat? There are chairs and the sun is not too bright."
Xu Yun had no objection.
At the same time, he looked away from Ye Duzheng.
He couldn't help but glance at the middle-aged man standing next to Ye Duzheng.
This man was about forty or fifty years old and dressed simply.
The hair on the forehead is sparse, the apples of the cheek are prominent, and the teeth are slightly buckled.
Do not know why.
Although Xu Yun did not recognize this person's identity, he always felt that he looked vaguely familiar.
If nothing unexpected happens.
This should also be a famous person.
However, the other party's appearance was not as distinct as Lu Guangda and Lao Guo could identify him at a glance, so Xu Yun could only temporarily suppress this feeling back to the bottom of his heart.
Anyway, we are going to chat next, and Ye Duzheng should introduce the identity of the other party.
...
The stone table was less than thirty meters away from where the few people were sitting. It was obvious that this was the place specially chosen by Ye Duzheng.
Come prepared.jpg.
Then several people walked for a while and soon arrived at the stone table.
Ye Duzheng first blew the dust on the stool with the strange man twice, dusted off the fallen leaves, and then sat down directly.
After taking a seat.
Ye Duzheng coughed lightly, patted the middle-aged man next to him on the shoulder, and introduced Xu Yun:
"Comrade Han Li, let me introduce to you. This is my good friend from Yanjing, Comrade Qian Yi."
"He is the workshop supervisor of the base boiler factory. He is currently responsible for some projects related to water heating. He stopped by and came out with me today."
Qian Yi?
heard this name.
Xu Yun's eyebrows under the bandage were raised heavily.
Mentioned it a long time ago.
Today's ordinary workers in Factory 221 may not be so mysterious, but scientific researchers basically use pseudonyms.
So from the moment I knew I had arrived at Factory 221.
Xu Yun had a very solid consciousness in his heart:
When you hear a person's name, you first suspect that it is a fake name.
The middle-aged man Xu Yun in front of him was vaguely familiar, and it was obvious that he could not be an unknown person.
In other words...
Qian Yi must be a pseudonym!
However, most people's pseudonyms generally do not change their surnames, which means most of the people's surnames are Qian.
etc!
Your surname is Qian?
Think of this.
Xu Yun stayed on the other party's plump apple muscles and hairstyle for another two seconds, and a guess suddenly emerged in his mind.
Could it be that this person is...
Academician Qian Bingqiong among the three coins?
Then Xu Yun quietly looked at "Qian Yi" a few more times, becoming more and more certain of his judgment.
After all, this apple-shaped skin and hair volume are so representative.
This is really old...
Qian Bingqiong was one of the main instigators of China's nuclear industry, and one of the earliest academic members of China - later academicians. His wife He Zehui was also a well-known female academician.
Done.
When later generations talk about the famous Three Qians, many people often think that Qian Bingqiong, Qian Weichang and Qian Xuesen are related by blood.
But in fact, these three brothers are not father and son, they are just branches of the same surname.
For example, Qian Bingqiong's branch is the Huzhou Qian family.
Mr. Qian Xuesen's family is the Qian family in Hangcheng.
Mr. Qian Weichang's family is the Qian family of Liangxi.
Among them, the Qian family of Liangxi also produced father and son Qian Jibo and Qian Zhongshu. Counting local family members, they produced dozens of Chinese academicians in total - this is really not an exaggeration.
For example, Qian Zhonghan, Qian Linzhao, Qian Lingxi, and Qian Yitai are all direct descendants or branches of the Qian family of Liangxi. If you write out all their names, I guess some idiot author will be scolded...
alright.
His eyes returned to reality.
At this time, Qian Bingqiong was sitting next to Ye Duzheng with a smile. He looked like an ordinary boiler worker or a passerby.
Therefore, Xu Yun had no choice but to pretend to know nothing and nodded to Qian Bingqiong, which was regarded as a greeting.
After finishing the polite greetings.
Xu Yun turned his gaze to Ye Duzheng again and asked him hesitantly:
"Director Ye, I don't know why you came to me today..."
Ye Duzheng was silent for a moment after hearing this, sighed slightly sadly, and said:
"Comrade Han Li, to tell you the truth, I came here specifically to answer your questions today."
Xu Yun blinked:
"Clear the confusion?"
Ye Duzheng did not directly explain the reason, but first raised a question:
"Comrade Han Li, my mentor is called Carl Gustave Rossby. I wonder if you have heard of this name?"
"Rossby?"
Xu Yun blinked and recalled:
"The one who studies atmospheric turbulence and boundary layer theory? The Rossby radius is also very famous, but I can't remember clearly whether he is from Germany or Sweden..."
It's a coincidence.
As a non-meteorological physics practitioner, Xu Yun only knew three or five meteorologists - of course, excluding Chinese seniors like Ye Duzheng and Zhu Kezhen.
And among these three or five people, Rossby happened to be there.
After all, this veteran introduced wave theory into meteorology and was a very famous physicist in modern meteorology.
In a sense.
His fame is almost as famous as that of Pieknis.
In addition, the Rossby radius is also a very well-known physical concept and has been widely used in later generations.
"Yes, that's him, a Swede."
Ye Duzheng raised his eyebrows and seemed a little happy that Xu Yun had heard about his mentor:
"Teacher Rossby is also one of the proposers of numerical weather prediction and has worked at both MIT and the University of Chicago."
"He returned to Stockholm ten years ago and served as the director of the Meteorological Center at Stockholm University. He passed away due to illness four years ago."
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The memory in Ye Duzheng's eyes faded slightly, replaced by a complex look:
"Instructor Rossby has always believed that the atmosphere above our heads is a random system. The so-called solving of the atmospheric wave equation is actually just finding an approximate solution rather than an exact solution."
"This is also a very mainstream view in the world. Even for a long time, I have held this attitude."
"but......"
Speaking of which.
Ye Duzheng couldn't help but glance at Xu Yun, exhaled a thick breath and said:
"But after Comrade Han Li helped me build that model, I feel more and more that this theory is not correct."
"I always feel that the atmospheric system is not completely random, but another very mysterious situation that can be calculated and controlled."
"More importantly...I did an experiment a few days ago."
Xu Yun was startled again and asked subconsciously:
"What experiment?"
Ye Duzheng pondered for a moment and picked up his briefcase from his side.
He rummaged through it a few times, quickly took out a black notebook, and handed it to Xu Yun:
"Comrade Han Li, take a look at this."
Then realizing that Xu Yun might not be able to pick up heavy objects yet, Ye Duzheng deliberately turned the notebook to the page he wanted to show.
Xu Yun lowered his head and glanced for a few times, then raised his head in surprise:
"Director Ye, this is...the simulation result of two meteorological data?"
"Yes."
The expression on Ye Du's face was very solemn. He pointed at the data above and explained:
"To be precise, this is the simulation result obtained from two sets of extremely small difference data."
"The circulation field parameters of the first data are 1., the parameters of the second data were rounded by me to 1.1452, and the remaining 19 sets of data are all the same."
"But...it's such a small difference, but the final derivation result is thousands of miles different."
"The weather will be sunny within seven hours in the former, but there will be a heavy rainstorm in three hours in the latter."
Ye Duzheng didn't even notice it himself.
When he said these words, his fingers were trembling.
In fact, as early as a week ago...that is, the night when the data model was derived, Ye Duzheng and Tao Shiyan had talked about some things.
At that time, he even named his guess the Taisu System.
But at that time, Ye Duzheng was more inclined to a conjecture without much actual evidence to support it.
The reason that prompted him to have this idea was not the data or phenomenon, but the meteorological model that he established with the help of Xu Yun, which had never been seen before.
But just a few days ago.
An accident happened.
At that time, in view of the huge contribution made by the Meteorological Center in weather forecasting, the superior department took the initiative to offer material rewards to the members of the Meteorological Center.
After declaring rewards to the group.
Ye Duzheng suddenly made a request out of nowhere:
He personally does not need any reward, he just hopes that the capital can spare a small part of the computing power of 104 computers to help him simulate the calculation results. The entire derivation process will only change one parameter.
After evaluation, the superior department believed that this request was not excessive, and allowed Machine 104 to cooperate with him in conducting a simulation.
But what I didn't expect was...
The results obtained from the two initial parameters 1. and 1.1452 are as different as the hair volume of Zhu Shimao and Chen Peisi!
This result also alarmed Mr. Zhu Kezhen in the capital, so Mr. Zhu changed his mind and intercepted the parameters from the middle part to modify the simulation.
Although the modification of non-initial parameters this time still resulted in some changes in the results, the difference was far less significant than the first time.
In other words...
The model constructed by Ye Duzheng is extremely sensitive to initial conditions.
At the same time, this sensitivity is not completely random, but a more complex discrete state - otherwise Zhu Lao's experimental results should be equally scattered.
Think of this.
Ye Duzheng couldn't help but take a deep breath and said to Xu Yun:
"Comrade Han Li, you know the principles of meteorological Doppler radar very well, and your knowledge of meteorological data is deeper than mine."
"So I came to see you today just to ask you one thing. What is the state of our atmospheric system?"
"Is it extremely accurate, or is it completely random? Or is it some kind of approximation that is infinitely close to accuracy?"
"...."
Looking at Ye Duzheng with a confused look on his face.
Xu Yun couldn't help but feel a strong sense of surprise in his heart.
If the weather Doppler radar was a backup he had considered when he was working on the damper.
Then Ye Duzheng's situation at this time was completely beyond his expectation, and could even be said to be far out of his control.
At least Xu Yun would never think of it anyway.
Ye Duzheng actually bypassed the numerical weather forecast and ran directly to...
Chaotic system!
That's right.
Chaotic system!
As we all know.
The modern physics community's understanding of the world is in a progressive state, and versions are constantly being optimized and updated.
First, Einstein's theory of relativity broke Maverick's absolute view of space and time.
Then the creation of quantum mechanics revealed the randomness and uncertainty of microscopic particle motion.
The third stage is the current period.
That is, the study of randomness in a deterministic framework leads to...
Chaos theory.
Chaos theory was first proposed in 1963, which is still some time ago.
At that time, meteorologist Edward Norton Lorenz established a simplified meteorological model to simulate weather conditions.
This model uses a total of 12 parameters to represent basic meteorological characteristics, such as air pressure, temperature, etc., which is much simpler than the 20 parameters used by Ye Duzheng at this time.
during a simulation.
In order to ensure the accuracy of the data, Lorenz decided to re-run part of the program.
But to save time.
He did not run the model from the beginning, but from a point in the middle of the run as a starting point.
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The program remains unchanged, and the initial point is the result of the last run.
So in theory, no matter how many times you run it, the final result will be the same.
But this time it's different.
At that time, the results of Lorenz's second operation were very different from the last time, and the deviation was irregular.
It's as if the result came from a completely different program.
After careful verification, Lorenz discovered that he had simplified a data by two decimal points during the copying process.
It is just such a small deviation that leads to completely different operating results.
Finally, Lorenz proposed the famous chaos theory in 1963, the most representative of which is the butterfly effect:
"A butterfly in the Amazon rainforest of South America, flapping its wings occasionally, can cause a tornado in Texas two weeks later."
Of course.
One thing that needs explaining is...
The original meaning of this sentence does not actually mean that "the wings of the butterfly caused the storm".
But...
[The causes of storms are so complex that we need to know the wings of every butterfly to be able to predict the outcome. 】
The emergence of chaos theory has completely pushed the physics world in another direction.
Think of this.
Xu Yun couldn't help but take a deep breath and made a decision in his heart.
Although Ye Duzheng's situation was not what he expected, there was no conflict between Edward Norton Lorenz and Xu Yun.
But how can there be any reason to evade such good things that are delivered to the door?
So Xu Yun pondered for a moment and quickly said to Ye Duzheng:
"Director Ye, to tell you the truth, someone in the Fengling Yueying Club has actually thought about the situation you mentioned."
"By the way, Director Ye, I wonder if you have heard of the story of Sisa Ban Dayil, the prime minister of King Sherhan of India, who counted grains of wheat?"
Ye Duzheng blinked and quickly gave the answer:
"Of course I've heard of it."
King Shehan rewarded the wheat.
This is a very famous mathematical allusion.
Anyone who played chess in a previous life should know this.
Legend has it that the inventor of chess was Sisa Ban Dayil, the prime minister of ancient India. The king at that time was Sherhan, known to the world as King Sherhan.
King Sherhan was very fond of chess, so he asked Dayir what reward he wanted.
Dayler left a classic saying that has been handed down from generation to generation:
[Please put 1 grain of wheat on the first grid of the chessboard, 2 grains on the second grid, 4 grains on the third grid, 8 grains on the fourth grid... that is, each
The wheat grains placed on the subsequent grid must be multiples of the number of wheat grains on the previous grid until the last grid, the 64th grid, is filled, so I am very satisfied.]
King Sherhan agreed to this request, but in the end he discovered that if he followed Dayir's calculation, he would have to pay for the entire kingdom's wheat grains for the next 2,000 years...
Then Xu Yun paused and said to Ye Duzheng:
"Of course, we can't tell whether this story is true or false, but we can see a truth from it."
"That is, if there is a small error δz0 in the initial conditions of a dynamic system, then during its evolution, this deviation will change in time t and an evolution function will appear."
Say it.
Xu Yun picked up the pen with some difficulty and wrote down a function:
|δz(t)|～|δz0|eλt.
Then Xu Yun drew a horizontal line under λ and continued:
"I call this λ the Lyapunov index, which represents the degree of sensitivity." (Note: Lyapunov was born in the 19th century, but the Lyapunov index was not proposed until the chaotic system was established)
"If it is a negative number, we will find that the initial deviation will be continuously smoothed out during the evolution process - which means that it is not sensitive to the initial conditions, and vice versa, it is extremely sensitive."
"In general dynamic systems, their evolution can always be described by such a differential equation, that is, d/dtx=f(x)..."
Look at what Xu Yun wrote eloquently.
Qiao Caihong, who has been [0v0] since leaving the interest group, couldn't help scratching his hair.
oops.
My head feels a little itchy, as if I'm about to grow a brain...
Actually.
What Xu Yun described to Ye Duzheng was exactly the feedback system and exponential divergence that were well-known in later generations.
This is also one of the few conceptual mathematical entry points for chaotic systems.
Of course.
There are also some Mandelbrot sets and polyfractal patterns in later generations, but these all require computer assistance.
After a while.
Looking at what Xu Yun wrote, a hint of enlightenment flashed through Ye Duzheng's eyes:
"...I seem to understand something. Comrade Han Li, the basic principles of the atmospheric system actually conform to the logic of determinism?"
"That's right."
Hearing this, Xu Yun felt slightly relieved and nodded vigorously:
"This system does not refute determinism, but because the equations of determinism have unpredictable phenomena, it makes this system worth exploring."
"It is a theory based on determinism, which uses determinism to derive unpredictable results - this is a very important concept."
In the later generations of Xu Yunlai.
There are two misunderstandings that often arise regarding the concept of chaotic systems.
One is that the existence of chaotic systems refutes knowability or determinism, and is the same concept as quantum uncertainty.
This is actually a very outrageous mistake.
Chaotic systems refer to being unknowable within a certain period of time, not uncertain, and it does not conflict with determinism itself.
At the same time, chaos theory is a purely mathematical mechanism, while quantum uncertainty is a physical mechanism - chaos exists in classical dynamics, but does not exist in pure quantum mechanics.
more importantly.
Chaos means the butterfly effect and the fractal structure of the phase space, which requires nonlinear dynamics.
The definite state in quantum mechanics can only be described in Hilbert space and is a linear state.
As for the second misunderstanding...
That is, chaotic systems are often inexplicably related to 'philosophy', and eventually go further and further away.
For example, as we talk, we will come up with the definition of Taoism, which means that Tao gives birth to one, one gives birth to two, two gives birth to three, and three gives birth to all things.
Then I will give you a WeChat at the end and add tmd to sell sandalwood...
Xu Yun has always been worried that Ye Duzheng will fall into these two traps, which will cause Ye Duzheng to have extremely serious research barriers in the future, and he may even become Li Huowang mentally.
Therefore, from the beginning, he worked hard to instill in Ye Duzheng the concept that chaos theory is a purely mathematical mechanism.
"Comrade Han Li."
Just when Xu Yun was almost finished explaining to Ye Duzheng.
Qian Yi, who had been silent for a long time...or Qian Bingqiong suddenly spoke:
"Comrade Han Li, so according to you, a large part of our world is actually non-linear?"
"So, wouldn't it be true that there are too few problems that linear equations and linear programming can solve?"
Hearing Qian Bingqiong's words.
Xu Yun couldn't help but glance at him.
Then he suppressed his excitement to see the elder, calmly shook his head and explained:
"Qian...well, Comrade Qian Yi, right? That's not necessarily the case."
"At least in my opinion, linear systems are actually an 'optimal linear approximation' of nonlinear systems."
"It retains the most important qualitative properties of nonlinear systems, such as stability or instability, that is, the topological properties of dynamic systems."
"According to the theory of differential topology, there are all nonlinear systems on smooth manifolds that can be linearly approximated."
Say it.
Xu Yun picked up the paper and pen again and started writing slowly.
As we all know.
Broadly speaking.
"Linear system" refers to a system whose solution satisfies the linear superposition principle, that is:
f(x_1 x_2 x_3 ...)=f(x_1) f(x_2) f(x_3) ...
This f cannot be simply understood as just a function form that can be written explicitly, but should be regarded as a mapping.
in short.
The corresponding linear system is linear mapping.
In the field of nonlinear research on ordinary differential equation dynamic systems, the form of the linear system is often like this:
\frac{dx}{dt}=a\cdot xwhere x=[x1,x2,x3,...]t.
And a is a constant matrix, then this is a linear ordinary differential dynamic system.
The nonlinear system that is different from it is a system represented by a system of equations that cannot be written in the above form.
For example, some are second-order, third-order, or higher-order systems, or the items in matrix a are formally related to the items of x.
Of course.
Nonlinear systems also include nonlinear systems in partial differential equations.
For example, systems with diffusion terms can form turing patterns.
But on the other hand.
The Koepka-Smale theorem mechanism in differential topology guarantees a dense situation:
Locally stable manifold after local linearization at operating points.
The corresponding linear system will have a stable subspace es and an unstable subspace eu, which are tangent to the corresponding manifold respectively.
That is to a certain extent.
Nonlinear systems can be treated approximately as linear systems.
"..."
after awhile.
Qian Bingqiong digested Xu Yun's idea, then frowned and said:
"But even so, Comrade Han Li, not all nonlinear systems can be approximated by linearization, right?"
"Or is it necessary to approximate a nonlinear system into a linear one, and a large amount of calculations must be completed?"
"That's right."
Xu Yun nodded sharply and affirmed:
"If you want to optimize the approximation as much as possible, you must complete a large number of calculations - this is the same as the exhaustive method."
“And if you want to do this, you must rely on another tool.”
This time.
Qian Bingqiong was silent for a longer time, and then slowly said:
"You mean...the computer?"
Xu Yun took a deep breath and quietly clenched his hands into fists under the table:
"Yes, computers. I personally think that this direction is one of the most important trends in the future."
"Even saying this... the 21st century will be the century of computers."
Qian Bingqiong suddenly shrank.
As the founder of Huaxia Atomic Energy Science, Qian Bingqiong is not proficient in computers due to professional limitations.
But his grasp of the overall situation is far beyond what others can achieve.
So throughout the conversation, he realized one thing:
If the world were truly non-linear...
Then the basic logic of future scientific development is to approximate non-linear things into linear states.
This so-called ‘thing’ could be the weather,
Maybe it's a theory,
Maybe it's the economy,
It could also be...
Technology and military.
And if that's the case.
Then the computer that Xu Yun mentioned is indeed an indispensable and important direction.
This is a truth that was discovered only after the chaos theory was proposed.
Notice.
Again:
This is not a philosophical topic, but a mathematical concept.
It just sounds a bit philosophical.
Nonlinear research emerged in the 1960s and did not officially enter the development stage until the late 1970s.
This concept directly promotes the development of many fields, the most representative of which is...
Computer Industry.
Financial chaos systems, neural chaos systems, and meteorological chaos systems in later generations are all based on computers.
Therefore, after Ye Duzheng raised the issue of chaos theory, Xu Yun immediately thought of this:
I had already laid the industrial software thread with Sun Junren, and if I were to lay the computer seeds again today...
That picture is so beautiful...
And know it.
The person sitting opposite him at this time was Qian Bingqiong!
A boss who is fully capable of understanding the concept he is talking about, realizing the value and passing it on to the decision-makers!
If the higher-ups really start taking computers seriously...
Oh my god.
The world seems to have changed a lot...
But that's okay.
The one being strengthened is the rabbit. Who doesn’t want their country to get better and better?
Xu Yun even wished that Rabbit could produce Gundam as soon as possible. Everyone would drive Unit 1 and show off what good style means in front of some houses that don't want to be housed!
So for a while.
The three people at the scene were all lost in thought. Only Qiao Caihong felt dizzy.
But after a few seconds.
Wuwuwu——
On a telephone pole not far from them, a loudspeaker suddenly sounded a piercing siren.
See this situation.
Beside the stone table.
Ye Duzheng, Qian Bingqiong and others' expressions suddenly changed, and they suddenly turned their heads to look in a certain direction.
Qiao Caihong also recovered from the o.o expression in an instant, and grabbed Xu Yun's wheelchair:
"Comrade Han Li, there's a situation! Let's leave quickly!"
.....
Note:
It’s Brother Donkey’s birthday today, please go to the character card and like it...