Although this word doesn't sound very nice, it looks a bit silly.
But looking at Xu Yun's social circle, there is only one person who can call him that.
That is
Isaac Newton, classmate of Mavericks.
only
Why did this letter from Mavericks come into my hands?
According to Halo's previous prompts, shouldn't the timeline in the instance be stagnant?
Think of this.
Xu Yun couldn't help but take a deep breath, cheer up, and continue reading.
"Mr. Fat Fish personally declares:"
"Mr. Fat Fish, it has been five years since you left without saying goodbye. Uncle William, Auntie and Lilani still miss you very much."
"At that time you only left a letter on the stall, informing you that you met your family near Grantham Parish, and then left without even paying for the meal."
"But thanks to you, our tomato sauce sales are very good, and with the help of the diocese, we have quickly occupied a large market."
"According to the original agreement, after deducting your living expenses, the total will be guineas. No, it is called pounds now, sixty-seven pounds."
"Considering that this letter may not be successfully delivered to you, I will temporarily keep these gold coins. The storage fee is 80,000% per day."
See here.
Xu Yun's eyes suddenly twitched, and he slapped himself on the forehead.
Good guy.
As expected of you, Mr. Niu, if you cooperate with me to save money, do you still have to pay the storage fee?
Moreover, the interest rate of 80% per day will be considered usury in 2022.
At least I should follow the example of those kind-hearted readers, and the updates I owe can be deferred without interest.
But soon.
Xu Yun gradually calmed down.
He still hasn't figured out how to send the letter, and no one knows whether he will receive those pounds next time.
Moreover, the current sales situation of "One Mantis Extermination" is pretty good, and Xu Yun's pursuit of money is not that urgent.
Therefore, rather than those pound dividends, he actually cared more about the other information that the Mavericks left in his heart.
For example
Timeline for sending letters.
According to the situation revealed in Maverick's letter, the time when he wrote the letter should be five years after he disappeared.
This is obviously something abnormal.
Because according to the original prompts of the halo.
The time inside the 1665 copy should be suspended and will not be restored until the next time you return.
But now it seems
Mavericks and the others seem to be able to 'move' again?
Think of this.
Another possibility suddenly popped up in Xu Yun's mind:
Could it be that
Is this the Mavericks in the deduction timeline?
This kind of guess can explain the origin of the communication, but in this case, what will happen next time I enter the 1665 copy?
If the two timelines influence each other, then Halo is undoubtedly slapping it in the face. This is a mistake that Halo should not make.
But if they are independent of each other, what is the meaning of this letter?
Why does it appear at this point in time?
even
Is there some unknown key to it and Lao Su's actions of burning money to visit his own grave?
“There is still too little information”
Xu Yun shook his head slightly and looked at the letter in his hand again, his eyes lingering on Lilani's name for a while longer.
Then he thought of something, and his expression suddenly relaxed:
"When I first met Lilani, she must have been only five or six years old. Even if five years have passed now, this girl would have been in her early teens until she was twelve years old."
"It's okay, okay, nothing happened yet."
Lilani.
She was the naughty child who gave Xu Yun a piece of cow dung when they met in dungeon 1665. She was also the person who, besides Hook, made Xu Yun the most unhappy during the deduction.
According to the deduction results of Halo.
This girl became more and more introverted after she left. When she was fifteen, she dropped out of school and went out to work.
When he was nineteen years old, he went to the Netherlands to find himself, but he encountered a shipwreck at sea and died unfortunately.
Today, Lilani is only twelve years old even if calculated according to the maximum age. She is still many years away from the age of 19 when the accident occurred, and she is still a lively little girl.
If Xu Yun could get in touch with Mavericks, he would have a chance to avoid the tragedy.
Think of this.
Xu Yun picked up the letter again and continued to read.
I saw the letter written:
"After you left, the plague gradually subsided. School reopened four years ago, and I returned to Cambridge University."
"Now I am the new Lucas Professor at Trinity College, Cambridge. Coupled with the dividends earned from ketchup, I have completely escaped the shackles of that woman and achieved financial independence."
"In recent years, relying on Han Li's expansion and Yang Hui's triangular model, I have re-established a new set of mathematical tools."
"And we have achieved considerable results in theory. The specific formula is as follows"
Looking at the flying handwriting on the envelope, Xu Yun could roughly picture Maverick's expression when he wrote this.
If nothing unexpected happens.
This content should be Maverick introducing his current situation, and the mathematical tool he mentioned is naturally calculus.
According to the original deduction of Halo.
In April 1666, Mavericks derived the third-order formula of Han Li's (Taylor) expansion, laying a solid foundation for calculus.
The time when Mavericks wrote the letter should have been between 1671 and 1672, and the calculus model must have been completely established.
Then he looked at some of the formulas Mavericks had added:
[If f′(x0)f′(x0) exists, there is f(x0+Δx) near x0x0?f(x0)≈f′(x0)Δxf(x0+Δx)?f(x0)≈f′(
x0)Δx.】
[Since Δx=x?x0Δx=x?x0, we can get f(x)=f(x0)+f′(x0)(x?x0)+o(x?x0)f(x)=f(x0)
This is a very basic differential formula, not much different from the one established by Mavericks in history.
But just watch and watch.
Xu Yun was suddenly stunned, and his expression gradually became serious:
"But during the derivation process, I suddenly discovered a problem."
"That is 'infinitely small quantity', 'infinitely close to', dx, these concepts seem to be very vague, sometimes it is 0 and sometimes it is not, which is confusing."
"So I spent another two and a half years and finally derived a more rigorous mathematical concept."
"If and only if for any ε, there exists a δlim0, such that as long as 0amp;amp;amp;limx-aamp;amp;amp;→δ, there is f(x)-Llimε."
"Then we say that the limit of f(x) at point a is L, recorded as: Limx-af(x)=L."
"In my opinion, this definition is truly "static", with no trace of movement or any ambiguity."
"Fat Fish, with your wisdom it shouldn't be difficult to see that it doesn't care at all how you approach L. It doesn't care whether you fly over or maneuver over."
"As long as the final difference is smaller than ε, I will admit that l is the limit of a."
"For example, we consider the simplest f(x)=1/x. When the value of x becomes larger and larger, the value of this function will become smaller and smaller: f(1)=1, f(10
)=0.1,f(100)=0.01,f(1000)=0.001”
"...It can be seen that when the value of x becomes larger and larger, the value of f(x) will get closer and closer to 0. Therefore, the limit value of the function f(x) at infinity should be
0.”
"Then take an arbitrarily small ε. Assuming ε=0.1 here, then we need to find a δ and see if we can find a range such that f(x)-0lim0.1."
"Obviously, we only need x→10; if we take ε=0.01, we only need x→100."
"Given any ε, we can obviously find a number that satisfies f(x)-0limε when x is greater than this number, and that's OK."
"How about it? Is my idea genius?"
A few minutes later.
Xu Yun raised his head from the letter with a look of admiration.
Although there is a very cliché saying.
But at this moment, he really wanted to take a breath and exclaim, "This kid is so scary."
As we all know.
The prototype of calculus can be traced back a long time ago, and many sages at home and abroad have proposed related concepts.
For example, Archimedes, Aristotle, Liu Hui, etc.
Based on the work of these predecessors.
In the mid-to-late 17th century, Newton and Leibniz independently created systematic calculus.
However, anyone who really knows the inside story knows that the calculus created by Newton and Leibniz is not perfect.
As Maverick said, it has a fatal flaw:
The concept of extremes is too great.
Therefore, many people tried to repair this defect. For example, McLaughlin tried to explain it in terms of instantaneous speed, Taylor tried to explain it using the difference method, and so on.
But from the perspective of future generations, their paths are obviously wrong.
Therefore at this stage,
Many people have criticized and questioned the calculus theory.
The most representative one is Bishop Baker, which was the first crisis in mathematics that we proposed a long time ago.
And what should we do to resolve the crisis?
The answer is simple, only if the concept of limit is truly rigorous.
Later, through the efforts of d'Alembert, Bolzano, Abel, Cauchy and others, they finally defined the definite integral as a sum limit.
Finally, Weierstrass, a great mathematician, filled in the last brick, and finally obtained the now common and logically rigorous ε-δ definition of function limits.
To know.
Weierstrass completed this achievement at the end of the 20th century, two hundred years after Mavericks and the others created calculus!
Available in this letter.
Mavericks actually single-handedly deduced the concept of limit to its final form!
True.
The Mavericks at that time had the help of Yang Hui's triangle and Taylor's formula, which were completely different concepts from the real Mavericks in history.
But the above two only play an auxiliary role, at most they make you more comfortable during the first few steps.
The real decisive factor is the girl's personal ability.
Looking at the letter in front of him, Xu Yun suddenly had another thought in his heart:
If Mavericks could come to the modern age like Lao Su, how high would his achievements be?
But soon.
Xu Yun shook his head and gave up the idea.
Lao Su's arrival in modern times was very accidental and had a very important connection with the background of the times.
It is too difficult to achieve the same rating in the 1665 copy.
Although the picture of Lao Su and the Mavericks flying together is beautiful, it is not possible to realize it in the short term.
Other than that.
If Halo can send this letter to him, it is obviously not possible for Mavericks to report his results. There must be some other purpose.
Maybe it's a mission, maybe it's something else.
Think of this.
Xu Yun lowered his head and read the letter again.
"The above are my discoveries in mathematics. If you have not dabbled in flux numbers, it may be able to bring you some inspiration."
"But I'm not writing to you this time to show off my achievements. I just want to swallow the money (scratch). I just want to ask you for help with something."
Saw this sentence.
Xu Yun suddenly became interested and read it carefully.
"In the process of studying gravity previously, I summarized and optimized some of Galileo's ideas."
"Some of them were solved smoothly, but some of them encountered problems. To put it bluntly, they were very serious problems."
"Fat fish, you should know that Galileo believed that there is no absolute reference system in the world, but only relative reference systems."
"So within an inertial system, it is impossible to measure the speed of the system through experiments."
"But in my opinion, time and space are two independent concepts. They have no connection with each other and are absolute."
"I believe that space is absolute. By its nature, it has nothing to do with anything outside and is always the same and immovable."
"For this reason, I also conducted a wooden barrel experiment to verify this conjecture. The specific diagram is as follows"
"There seems to be no logical problem with this experiment, but then I conducted further research on the dispersion phenomenon that occurred in you."
"How should I put it? I found that the nature of light seems to be much more complicated than I originally thought."
"Fat Fish, I remember you said that you were a teaching assistant at the School of Natural Sciences at Leiden University in the Netherlands, so I wrote this letter with strong doubts and expectations."
"If you can receive this letter and can answer my questions, please give me a reply as soon as possible."
The letter ends here.
There is a name written on the lower right:
Isaac Newton
After putting down the letter.
Xu Yun gently rubbed his nose, his chest rose and fell a few times, and he exhaled a heavy breath.
In the 21st century.
Some marketing accounts often say this:
"Newton's theory is wrong, and his theory has long been overturned by Einstein!"
Some of the videos talk about people with noses and eyes. At the same time, because physics is a subject with very clear barriers, some people don’t understand many of the inside stories at all, so that’s what Mihu Lake believed.
But what actually happens?
The truth is this:
Newton put forward many theories in his life, one of which was half right, and one of which was completely wrong.
All the remaining theories and the system composed of them are alive and well, and they are the real cornerstone of our macroscopic world.
Let’s talk about the half-right theory first.
This theory is the particle theory of light that Maverick insists on.
At that time, Mavericks collected a large amount of evidence that light was particles through his own research, and then promoted the particle theory and became a representative figure of the particle theory of that era.
There is really nothing to say about this matter. No one knew about the wave-particle duality of light before 1909.
After all, no one could have imagined at that time that this thing was so weird and had such super-class abilities as duality.
It's like a person whose gender cannot be identified enters the men's room first, has a squirt in front of other boys, and then goes to the women's room and squirts again.
So the boys said that the person was a boy, and the girls said that the person was a girl. Both parties believed that what they saw with their own eyes could not be wrong.
The results of it.
Finally, the school went to the hospital for a checkup and found out that this person's gender was Hideyoshi. Where can you explain this?
Therefore, Mavericks's speculation on the particle theory can only be regarded as the limitations of the times, and many of the old people who overturned it later are stupid.
As for that completely wrong theory?
It is the absolute view of time and space proposed by Mavericks.
Maverick proposed this idea in "Mathematical Principles of Natural Philosophy", in which he described an absolute view of space and time:
Speed is a function of time, space and time are independent of each other, and there is uninterrupted passage of time and expansion of space.
In other words.
He believed that time and space exist independently from the movement of objects.
To this end, he also conducted an experiment, which was the barrel experiment mentioned in the letter.
This experiment is actually very simple, even a new student can complete it very easily:
first.
Use a long soft sling to lift a bucket of water and twist the sling into a twist.
If you hold the hanging rope and don't let the twist-shaped rope loosen, then the bucket and the water in the bucket are relatively still, and the water surface is flat.
But you suddenly let go of your hand, and Mahua begins to relax.
The hanging rope will start to rotate, and the bucket will also rotate with the hanging rope.
Initially, the water in the bucket does not rotate, only the bucket rotates, and the bucket and the water in the bucket rotate relative to each other.
But slowly.
The water was driven by the bucket and began to rotate.
By the end, the water was spinning like the bucket.
At this time, the water and the bucket are relatively stationary and not rotating.
But the water surface is concave, with a low center and high sides.
Of course.
The operation is simple, but the idea is very sophisticated:
First, or idea 1, we can calculate the angular velocity Ω of the water rotation from the shape of the water surface.
Idea 2, we observed an objective experimental phenomenon:
at the begining.
The water in the bucket has the greatest relative motion, but has no tendency to leave the axis of rotation.
The water neither moves toward the edge nor rises, but remains flat, so its circular motion has not really begun yet.
Three points can be drawn from 2:
3. This reference system is not a bucket.
4. This reference system is not the water body itself.
5. There are only water, buckets and space in this system.
A final conclusion can be drawn from 3,,4,5:
6. This reference system can only be relative to space itself, so this objectively existing space is absolute space.
Follow the original trajectory.
Mavericks had no doubts about the results of this experiment, so he proposed the absolute view of time and space, which became the biggest stain against him by the sunspots of later generations.
Everyone should know what happened next.
Einstein proposed the theory of relativity and believed that space and time are one thing and the two are inseparable.
In Einstein's view of time and space.
Everything moves at the same speed in space-time, which is the speed of light.
What moves fast in space will move slowly in time, and the total speed will always remain the speed of light.
The structure of space-time is the gravitational field. The two are inseparable, and they are also inseparable from the material field.
Space tells matter how to move, and matter tells space how to curve.
If compared from a mathematical perspective, Newton's view of space and time is undoubtedly R^3xR.
It is a straight three-dimensional Euclidean space plus a one-dimensional time that has no connection with it. This structure is very simple.
Einstein's space-time is M^4, and the four-dimensional curved Riemannian space includes three-dimensional space and one-dimensional time.
You can imagine that this is a four-dimensional curved "surface", whereby time and space are coupled together, and its metric tensor is the gravitational potential.
Very simple, right?
Then Xu Yun thought about it.
Subconsciously, I planned to take out a pen and paper from the backpack beside me.
But he soon laughed at himself. He was in space right now. Where did he find the paper and pen around him?
But just as he was about to return to reality, he suddenly appeared in front of him
A ballpoint pen and a piece of paper.
""
Xu Yun took the pen and paper, looked around the space a few times, and shouted:
"Boss, how about another table and chairs?"
After a while.
stop
A table and chair appeared in front of Xu Yun, and a photo of Jiaran's face was posted on the right front of the table.
Xu Yun: ""
There is indeed something wrong with this space, right?
Then he shook his head and forced himself to get rid of distracting thoughts.
Sitting in a chair, he wrote a reply to Mavericks:
"Dear Mr. Newton:"
"Mr. Newton, long time no see, I'm Fat Fish."
"If you still have the draft paper I originally wrote to you, you should be able to confirm my identity by comparing the handwriting."
"I am very happy to receive your letter a few years later, but I would like to explain to you first that I have suffered from severe asthma in the past few years. My family arranged for me to take a vacation in a remote place. It was not until recently that I gradually recovered.
.”
"I am traveling around Europe at the moment. If you want to see me for anything, just send it to the original address.
"My assistant will forward the letter to me, but due to travel problems, there may be some lag in my reply time."
"As for the dividend guinea, I'll leave it with you first."
Finish writing these.
Xu Yun paused and re-examined the contents.
After making sure that all the miscellaneous matters were taken care of, he continued to write:
"The mathematical tools you invented are really amazing. This is a height that I can't reach independently. Please allow me to pay you high respect here."
"But as for the barrel experiment you mentioned, I have some other opinions."
"I can probably understand your idea, and it seems quite subtle at first glance. There are a total of these six incremental ideas."
"But have you ever thought that you made a mistake in your thinking in step five?"
That's right.
Among the six derivation designed by Mavericks, the fatal flaw is in the fifth step.
In step five.
The calf sees water, buckets and space as a system.
But in fact.
The correct combination of this system would be water, buckets, and everything else in the universe.
The inertia of water is the result of the interaction of water with the bucket and all other matter in the entire universe.
In other words.
The angular velocity Ω at which this body of water rotates is relative to the angular velocity of all matter in the entire universe except water.
Xu Yun then pondered for a moment and wrote his rebuttal thoughts into the letter:
"We assume that there is only this bucket of water and this bucket in this universe."
"Then the experimental phenomenon you conducted will become like this: at the beginning, the relative motion of the water in the bucket is the largest, and the water surface immediately becomes a concave surface."
"As the relative motion of the water and the bucket decreases, the water surface gradually becomes flat. The angular velocity calculated at the beginning of the experiment is the speed of the water body relative to the bucket."
"In other words, what you call absolute space is actually the bucket reference system when there is no other matter in the universe."
"Then let's assume that we are still in our universe, but the mass of our bucket is smaller than the root of an ear, and is as big as the Earth."
"Then the bucket starts to rotate, and the water surface will immediately start to change."
"Then the spin angular momentum of the central mass and the revolution angular momentum of the surrounding mass will conform to a certain function, that is, the sum of the rotational inertia of all matter in the universe is 0."
Friends who have attended graduate physics should know this.
Xu Yun's explanation idea is an intrinsic reference point theory that is very friendly to beginners.
That is to say, the reference system within the target area boundary action area, and each stationary space within the area relative to this reference system are defined as the intrinsic reference points of the area.
The intrinsic reference point as a whole has a common motion, and the acceleration generated by various external forces is also the same.
Therefore, the positions of the eigen reference points remain unchanged relative to each other.
Assume that the intrinsic reference point has a sudden static state out of nothing, and the object analyzes its force and motion to make it always stationary.
Then its force and acceleration correspondingly balance and cancel each other.
As for the second example mentioned by Xu Yun, it is actually an astronomical concept called "drag effect", which belongs to the cutting-edge theory of space-time curvature.
In fact, in later generations.
What gave the final blow to the calf barrel theory was a 48-year long experiment.
This experiment is called Gravity Probe B.
Its core purpose is to precisely measure the geodesic drift and inertial reference system drag near the Earth to quantitatively test the general theory of relativity.
Its main device is an extremely precise gyroscope placed on a satellite. The orbit of the satellite is circular and passes over the north and south poles of the earth.
At an altitude of 642 kilometers above the ground, it measures the rotation of the gyro axis relative to the starry sky background.
Calculated according to general relativity.
On this satellite, the geodetic drift of the gyro axis and the drag of the inertial reference system are 1.8 thousandths of a degree per year and 1.1 thousandths of a degree per year respectively.
Gravity Probe B was hosted by Professor Eve Ritt of Stanford University and started in 1963 until it ended in 2011.
It was supported by NASA for the first 45 years, and it is also the longest-supported project by NASA, costing a total of US$750 million.
In the past three years, funds raised by a Saudi prince who received a PhD from Stanford University cost more than US$30 million.
What?
You ask why we spent 750 million in the early 45 years and only spent 30 million in the last three years?
Don't ask, it's inflation.
Of course.
Although there is a lot of oil and water in this plan, the funds that will eventually be implemented are still a very huge number.
However, despite the huge amount of time and money spent on Gravity Probe B, the results were not ideal.
According to the original declared goal.
Gravity Probe B can provide geodetic drift data with an accuracy of 0.01% and inertial reference system drag data with an accuracy of 1%.
The accuracy of the final results was only 0.28% and 19% respectively, which was more than twenty times worse than the expected accuracy.
But on the other hand.
Although the accuracy varies greatly, it still successfully used a gyroscope to directly falsify the conclusion that "once the axis of a gyroscope without external interference points to a certain direction in the background starry sky, it will always maintain this direction."
This completely refutes Mavericks' absolute space-time view in reality by combining it with the theoretical argument, which is considered a complete conclusion.
By the way.
Eve came to China in the early 1980s, hoping to recruit a well-known Chinese gyroscope expert in the Seventh Machinery Department.
But this request was ultimately rejected by us because we were worried that the experts would not be able to come back.
The expert that Eve once had her eye on was named Gao Bolong, a pioneer who had achieved astonishing achievements in China's fighter jet industry and a true meritorious service.
Three years before his death, Mr. Gao was interviewed by Southern Weekend.
During the interview, he said something very touching:
"They (across the sea) proposed fifty times the annual salary, settled in U.S. dollars. At that time, we were short of foreign exchange to the point where we were almost selling our blood. The foreign exchange reserves in 1980 were negative 1.3 billion, yes, negative."
"So I discussed it with the minister. I said, minister, if I go to the other side of the sea, I probably won't be able to come back in this life. I think it's a good deal to exchange for such a large amount of foreign exchange. I have this understanding.
, why don’t you go up and think about it?”
"The minister scolded me on the spot and told me not to even think about it. Talents like you can be of great help to the country in the future. It would be a sinner to let you go for a little foreign exchange!"
"Then I stayed in the country and lived up to the country's expectations. Everything we fly in the sky has something to do with me. I will be able to explain it to the minister when I meet him in a few years."
How deplorable, how admirable.
The topic returns to its original place.
In fact, it follows the normal trajectory.
Mavericks insisted on his absolute view of time and space until his death. In theory, such doubts would not arise.
So it's obvious.
Maverick's original strong concept must have been broken by certain circumstances, causing him to have some irreversible wavering.
Think of this.
Xu Yun couldn't help but cast his eyes to the end of Maverick's letter, and stayed for a few seconds on the sentence about dispersion.
As we all know.
The interaction between substances is realized through fields, so it is called field interaction for short.
Field speed is the speed of field propagation. It is generally believed that the speed of light is the same as the field speed, and light is the propagating electromagnetic field.
In other words.
In Maverick's absolute view of time and space, the attribute of light is particles.
And judging from the end of Maverick's letter
He seems to have discovered some abnormalities in the properties of light by studying the phenomenon of dispersion?
"This is probably the most likely scenario."
within space.
Xu Yun touched his chin and frowned slightly:
"It's just that Mavericks didn't mention the anomalies he discovered in the dispersion phenomenon in his letter. If he had done a double-slit interference experiment, let alone the difficulty of doing this experiment in the 17th century, his tone was absolutely impossible.
So hesitant”
Think of this.
Xu Yun hesitated for a moment, thinking about something in his mind.
Finally, I picked up a pen and paper and wrote the last sentence on the letter:
"Mr. Newton, although I don't know your doubts, have you ever thought about it?"
