Chapter 145 The calculation result that is 863 years ahead of Europe is born! (6.8k
Look at Xiao Li who opens his mouth scientifically and shuts up scientifically.
In the end, Lao Li gave up the idea of setting up a blind date for his daughter.
In fact, this is normal.
After all, in the normal trajectory, the combination of Xiao Li and Zhao Mingcheng is actually somewhat reasonable.
There is definitely a mutual affinity between the two, but there is also a certain exchange of interests at the family level:
Zhao Mingcheng's father, Zhao Tingzhi, was a member of the Yuanfeng Party, that is, he firmly supported the reform or neo-law faction, and was an old enemy of Li Gefei.
However, Song Huizong had just come to power at this time, and the old and new parties were relatively restrained, and many people chose to marry each other to ease their relations.
Among them, the combination of Xiao Li and Zhao Mingcheng has certain related factors, otherwise Lao Li would not have agreed so quickly.
Of course.
In later generations, when talking about Xiao Li Zhao Mingcheng's marriage, generally no one will mention the exchange of interests too much.
After all, for young people, love should be pure and innocent.
But in ancient China.
How many men and women who were born into official families can truly pursue untainted love?
For example, many people in later generations know that Xiao Li and Zhao Mingcheng are extremely affectionate, and they can be called an imitation couple, a couple of gods.
But few people know that they separated not long after they got married:
In more than a year, Song Huizong will use Cai Jing to cleanse Sima Guang's old party, which he hates.
At that time, Li Gefei, as a protégé of Su Shi, the big V of the old party, would naturally be classified into this camp, lose his job and be sent back to his hometown.
Zhao Mingcheng's father, Zhao Tingzhi, relied on his status as a member of the Yuanfeng Party to advance his official career to three levels, and was once in the limelight.
At that time, Xiao Li asked Zhao Tingzhi for help and asked his father-in-law to exonerate his father.
Who knows.
What she was waiting for was not only her father’s pardon, but the Zhao family’s clearing of boundaries:
Taking advantage of the court's new policy that "clan members are not allowed to marry the descendants of Yuanyou Party members," the Zhao family drove Xiao Li out of the capital even though they were not members of the clan.
Xiao Li's sentence "What's popular is hot but the heart is cold" was written in this context.
Then a few more years.
Cai Jing was dismissed as prime minister and all members of Yuanyou's party were rehabilitated, and Xiao Li was able to return to Beijing to reunite with Zhao Mingcheng.
However, things turned upside down. Cai Jing returned to the throne the next year, and Zhao Tingzhi, who had been fighting for power with Cai Jing in the past few years, suddenly died of illness.
Ever since.
Cai Jing took action and the entire Zhao family was collectively thrown into prison.
Among them, Zhao Mingcheng spent several months in jail. Because he had no charges, he was released. However, he lost his official position and his house.
So he could only live in seclusion in Qingzhou with Xiao Li, which was the ten years when the couple was most loving.
Then came the resurgence of Zhao Mingcheng. As soon as Zhao Mingcheng, who had spent little time with Xiao Li and separated a lot, left Li Qingzhao's sight, he immediately took in several concubines - some people in later generations still practiced this. This was a routine operation in ancient times. Li Qingzhao's " "Feelings·Preface" and read it?
A few more years.
Zhao Mingcheng also made a saucy trick of abandoning the city and running away from the prefect. Xiao Li wrote the most powerful poem in his life: "I still miss Xiang Yu and refuse to cross Jiangdong."
Since then, the relationship between Xiao Li and Zhao Mingcheng dropped to a freezing point, and Zhao Mingcheng eventually died of depression.
It can be said that.
The relationship between the two begins with love and ends with contempt.
Let me ask you about this Xiao Li.
Really happy?
It was obviously true in those ten years in Qingzhou, no one can deny this.
But what about those six years of being expelled from the capital, and those years after the separation?
What about the entire marriage?
Xiao Li's subsequent lyrics are enough to explain everything.
Xu Yun liked a saying in later generations. It's better to call it a nightmare than a sweet dream.
Because nightmares are just dreams after all.
No matter how many desperate situations you encounter in your dream, as long as you wake up from the dream, at least everything will not be worse.
But sweet dreams are different.
Once the dream is broken, this gap may even completely defeat a person.
Although middle-aged Xiao Li was not crushed by the shock of his broken dream.
But it is not difficult to see from the words that her mood has undergone many pessimistic changes.
Therefore, maybe in this timeline, it is a good thing that Xiao Li did not meet Zhao Mingcheng
Of course.
At this time, Xu Yun did not know what happened in Li Mansion.
After leaving the mysterious man's home, he went straight back to Lao Su's house and began to prepare his own lesson plan.
The next day.
Xiao Li arrived at the house on time, but Xiao Zhao was nowhere to be seen, just as Su said.
At the same time, Xu Yun also noticed.
There seemed to be something wrong with Xiao Li's mood. He was excited but also had a hint of worry.
However, Xu Yun did not choose to get to the bottom of the matter. After all, being able to come to class meant that there was nothing wrong with the girl.
"What we are talking about today is acceleration, which is a physical quantity that describes how fast the speed of an object changes"
The initial concept of acceleration is not difficult. To put it simply, it is a vector generated by force.
In later textbooks, acceleration is mainly explained through the motion state of an object, and then extended to uniform circular motion and so on.
But in fact, if you want to understand acceleration, it is easier to start from the unit, which is also a little trick of Xu Yun:
The unit of acceleration is m/s, the unit of velocity is m/s, and the unit of time is s.
When the speed of an object changes within a period of time, divide the change in speed by the period of time, and you can find m/s/s = m/s, which is the unit of acceleration.
More than an hour later.
Looking at the confused Xiao Li, Xu Yun smiled slightly:
"Miss Li, is it very simple?"
Xiao Li stared at the mosquito-repellent incense:
"@@"
While Xu Yun was instilling knowledge into Xiao Li.
Outside the courtyard gate, which was used as a temporary classroom, there was a sudden knock on the door:
"Wang Lin! Wang Lin! Open the door quickly!"
When Xu Yun heard this, he subconsciously looked at Lao Su who was listening.
Then he quickly walked to the door and took off the bolt.
Just opened the door.
Then he saw Lao Jia standing outside the door with his hands behind his back, a look of urgency on Sun Xiaochuan's face.
Seeing this, Xu Yun quickly gave a junior salute and said:
"Tongyu first"
As a result, before the greeting was finished, Lao Jia grabbed him and said:
"Wang Lin, cosine, cosine, is cosine!
Multiple cosines can be accumulated to get a certain value, somewhere between one and a quarter and one and three thirds, right? ? ”
Lao Jia's words seemed to have no beginning and no end, and the meaning was unclear, even a little like he was drunk and crazy.
But when he heard the word cosine, Xu Yun suddenly felt a huge wave in his heart:
Oh my god!
No way?
Lao Jia and the others actually calculated the cosine category of the incident wave?
This tmd is already an envelope concept!
Even though Xu Yun had a big heart, he couldn't help but beat in shock at this moment.
This.
Isn't this too outrageous?
But according to the last value that Lao Jia said, this is clearly the specific mathematical solution of the Helmholtz equation in the light field!
To know.
Before giving the calculation to Lao Jia and the others, Xu Yun once performed a simple calculation on the convex lens. After all, the person who asked the question himself had to know the answer.
The calculation process is very simple:
That is, a simple calculation based on the original algorithm using Green's theorem to solve the wave equation and spherical waves as the basic elements.
The final curved state value is about 1.2993.
The one and a quarter to one and three quarters mentioned by Lao Jia are 1.25-1.33.
It's obvious.
This is a similar set of answers.
Although the calculation error of this thing will generally not exceed six decimal places in later generations, and some will not even exceed eight decimal places.
But what are the calculation conditions for future generations?
In ancient times when there were no systematic precision values, this error was actually quite terrifying.
Think of this.
Xu Yun couldn't help but raise his head and looked at Lao Jia in front of him.
After several days of calculations, Lao Jia's already stinking complexion became darker and more haggard.
His hair was messy, and there were a lot of ink stains on his cuffs and collar.
But the eyes of everyone on the list were still as sharp as falcons, looking directly at Xu Yun, as if there was a fire burning in them.
Xu Yun had no doubt at all.
If he said "the data is wrong" at this time, the old man would not be discouraged at all.
He would immediately turn around and go back to the study to recalculate the data with several other people.
Then he took a deep breath and said solemnly:
"The numbers calculated by Mr. Tongyu are almost consistent with those recorded in the sect's handwriting, and the difference is very small.
But just in case, could you please let me take a look at your manuscript first?”
"It's simple."
Lao Jia Jian said, grabbing Xu Yun's wrist and dragging him away:
"Just come with me to the study!"
Xu Yun watched this little old man who was in his eighties and almost ninety years old dragging him along like a chicken. He couldn't help but glance at his right hand in confusion, and had doubts about the basic skills that Wang Zhen had been practicing these days. Deep doubt:
".?"
When Old Su in the hospital saw this, he turned to Xiao Li and said:
"Qingzhao, let's go and have a look too. If nothing else happens, the preparation of high-power microscopes and telescopes should be put on the agenda."
Ever since.
The class was interrupted unexpectedly, and the group followed Lao Jia to the study.
As soon as he entered the house, Lao Jia shouted:
"Everyone, I have brought Wang Lin."
Hear this.
Han Gonglian and others who were staying in the study suddenly looked shocked and stood up one after another, ready to say something.
But before they spoke, Lao Jia continued:
"Wen Yi, please get our manuscript first."
Han Gonglian was stunned when he heard this, and then came back to his senses.
I saw him picking up a few manuscripts that he had prepared long ago from the desk, sorting them out briefly, and quickly came to Xu Yun:
"My lord, here are all the manuscripts."
Xu Yun thanked him, found a location with good lighting, and checked the manuscript.
Lao Jia and the others suppressed their voices very wisely. Even though they had a lot to say in their hearts, they were forced to hold it back at this time.
The manuscript given by Han Gonglian is about ten centimeters thick, with a large number of numerical symbols densely written on each piece of paper.
The manuscript not only records the entire calculation process, but also serves as a memo or diary, recording a lot of daily deductions.
"The outer half of the square is a moment, and when it is circled, it forms a total of three numbers. The total length of the two moments is twenty and five, which is called a product moment."
"The outer corner of the lens is green, and the line length is five and three-quarters. It is also recorded in Arabic numerals, which is 5.75"
"The complex moment in the lens reaches Sichuan, the line length is three and one-fifth, and it is recorded in Arabic numerals, that is, 3.20"
"The bottom corner of the central axis is engraved on the meridian corner. The total number of groups engraved on the secondary axis is 1,737. Liu Yi and Xiong Huan are divided into 1 to 388."
"Three diameters are one, divide them to create a square."
"Suppose the unknown is Tianyuan. If you open many small holes to let light through, you can get some variable values. It's very strange. Very strange. Can it also be tangent to light?"
"Today Zirong arrived again and advised us to eat and sleep as early as possible, but because of his excitement, he and I did calculations until late at night, and told us about the 'particle theory', which suddenly enlightened us"
"If light is also a tiny object, its deflection state can also be calculated in detail. The next day, more than 5,300 groups of rectangles were calculated, and a constant number was obtained, which is approximately ."
"Between one and a quarter to one and three quarters"
See here.
Xu Yun couldn't help but bite his back teeth hard, trying to avoid losing his composure.
But even so, his fingers were still trembling.
There is no other reason than Lao Jia and others
This time it’s really awesome.
As everyone knows.
In Fourier optics, any complex wave can be represented by spherical waves and plane waves.
Complex function = a DC quantity 0-order Fourier term + Fourier higher-order term.
That is to say.
Spherical waves and plane waves are the basic solutions to the wave equation.
The complex amplitude of the plane wave can be expressed as aexp[jk(xcosα+ycosβ+zcosγ)].
cosα+cosβ+cosγ=1, which is the direction cosine of the plane wave.
Based on this, the tilt factor K(θ) of Kirchhoff's diffraction theory can be obtained.
Of course.
The deeper reason is that every point on the forward moving wave can be regarded as a source of secondary waves.
The encompassing surface of each wavelet source wave surface is the next new wave surface.
θ is the angle between the position direction and the normal line of the wave surface, which involves the wave nature of light.
Very simple and easy to understand.
all in all.
If Kirchhoff's theory describing the coherent superposition of spherical wavelets is called the spherical wave theory of diffraction.
Then the angular spectrum theory is the plane wave theory of diffraction.
Kirchhoff's original calculation method was through vectors. In addition to integrals, mathematical tools also included Green's formula and so on.
At that time, the field of mathematics was finally approaching perfection, at least it would not always talk about a crisis in mathematics, or the collapse of the mathematics building.
The calculation method used by Lao Jia and others is much "stupid":
The interval is locked through a trigonometric method similar to exhaustive comparison, and then the calculation is performed using the most original Jia Xian triangle binomial.
As for the core idea of this algorithm.
Of course it is the microscopic theory proposed by Lao Su.
According to the manuscript of Lao Jia and others, although they did not realize the wave-particle duality of light, they had the idea of dividing light:
They divided the deflection area into countless tiny parts, intercepted five or six key deflection areas, and used them to calculate the tangent line.
This approach is theoretically feasible.
But if there are only a few data, the calculated deviation value may be very large.
So in order to reduce this error, Lao Jia and the others not only used the binomial division remainder of Jia Xian's (Yang Hui) triangle, and then...
Categorize and compile all data.
Or to be more precise, it’s hand calculation.
The number of classified data is the last mentioned.
More than 5,300 groups.
This is undoubtedly a huge amount of calculation, especially for the elderly group in front of them. They may need to spend more energy to persevere.
As for the derived value of one point or several, what does it mean?
Put it this way.
As long as further summary statistics can be carried out.
Not to mention whether there is a chance to discover the half-wave band method, but it is still easy to derive the formula f=(l^2-d^2)/4l.
Once this formula is derived, it can be said that the only limit to lens grinding is the level of industrial hardware.
Friends who have studied optical physics should all know this.
The first thing that appeared in the West was the Huygens-Fresnel principle, which was Xu Yun's original goal, and it involved scalar problems.
The Gens-Fresnel principle is not a strict theoretical product, but is derived from simple intuition to a large extent.
Therefore, it is impossible to explain why "the superposition of all sub-wavefronts is to obtain their envelopes", but it can be used as an introduction.
Still the same sentence.
Sometimes less complete concepts can save effort and be easier to understand in the ancient context.
But what Xu Yun didn't expect was.
After several days of hard calculation, Lao Jia and others.
He unexpectedly touched upon the fourth level that he originally called, which is the concept of Maxwell's realm!
True.
Lao Jia and others have only touched upon this field in a very small way, and there is still a long, long way to go.
Just like in the national college entrance examination, you deduced a certain formula and accidentally became the only person in the country who solved the last math question.
But other than that, you can't do all the math questions, and you only get 20 or 30 points in all subjects.
Therefore, from the perspective of knowledge structure, this problem solving is actually useless. You can't even pass the vocational high school entrance examination.
If you want to truly master relevant concepts, you have to learn a lot of things such as minimum optical path, half-wave band method, perturbation contribution expression, etc.
But on the other hand.
You did solve that question. That question that many candidates may not be able to solve even after graduating from college. Uncle Ge x in the question group just wanted to torture people.
This is an achievement that cannot be ignored and has certain practical value:
In this kind of topic, as long as you want to, you can make some money by opening a self-media account. You can make more or less.
So this is the situation of Lao Jia and the others:
They have this "hot topic", but they don't know how much value they can create.
If it were a normal situation, Lao Jia and the others would most likely be just a flash in the pan, just like Lin Huan who said "There is no difficult test paper in the eyes of Hangzhou experts".
But the problem is
What's more, they forgot that Lao Jia and the others also had Xu Yun, a big wall-hanger.
Who knows whether a bunch of fire today may turn into a scorching sun in the future?
Think of this.
Xu Yun couldn't help but feel excited again.
Judging from the abilities displayed by Lao Jia and others, their knowledge of knowledge is obviously higher than their expectations.
In Native History.
Kirchhoff's diffraction theory would not be formally proposed, or completed, until the end of the nineteenth century.
Although today's year 1100 AD is said to be the twelfth century AD, in terms of timeline, it is just stuck in the transition year between the two worlds.
So it can be said.
Lao Jia and others were 863 years ahead of Europe and first proposed some concepts of lens diffraction!
Lens diffraction.
This is a very elastic area.
It may be unknown, or it may have a profound impact.
Xu Yun doesn’t know what changes it will have in the future of China’s history in this timeline, but at least he can be sure
Telescopes and microscopes can be prepared now. (End of chapter)