It is not difficult to see from the literal meaning.
The theoretical research department led by Lu Guangda is undoubtedly the absolute core project in the entire nuclear weapons development process.
So from the perspective of future generations.
Naturally, this department should be placed in the frontmost branch factory, so as to reflect the importance of the entire department, right?
However, the answer is not like that.
Actually.
The area where the theory department is located is neither the first branch nor the second branch, but the serial number looks ordinary...
Branch No. 7.
The Seventh Branch is located in the southwest of the base and is responsible for theoretical research and experiments on radiochemistry and neutron physics.
This is an area with many dense buildings, but most of the buildings have ordinary factory buildings on the outside, and are unique inside.
After passing the first round of inspection by the 'guards' at the factory gate, Xu Yun and Lao Guo successfully entered the factory.
As for Qiao Caihong...
Naturally, this girl was called by Lao Guo to take care of Yang Kaiqu because she was not at a confidential level.
So Xu Yun enjoyed the treatment of a big old pushcart again.
"Xiao Han, by the way, this is your first time coming to the Seventh Branch Factory, right?"
After entering the factory area.
While pushing Xu Yun's wheelchair, Lao Guo pointed to the black shell-like factory areas around him and said:
"How is it? Does it feel a little different from the theoretical research center you imagined?"
Xu Yun was silent for a moment and nodded slightly:
"Well, it's a little different."
Although Xu Yun once visited the Xihai Atomic City in reality, the overall appearance of the later Atomic City as a themed commemorative scenic spot is actually very different from the current 221 Base.
Quite a few objects from the Atomic City have been moved to museums, and many buildings have been abandoned or even demolished altogether.
Therefore, Xu Yun did not see with his own eyes the situation in the theoretical department where Lu Guangda and others were working. The picture he originally conceived should be like this:
Several two- and three-story small buildings are gathered together. The exterior walls of the buildings are a bit dilapidated, but they don't feel abandoned. There is a yellowish stone road in front of the door, and there are some plants and flowers on the roadside.
Whenever the sun shines down, it flickers through the leaves, forming mottled shadows, elegant and long.
Unexpectedly, Xu Yun found out after seeing the actual situation...
The style of the Theory Department was simpler than he imagined.
But if you think about it carefully, it's normal.
After all, in the original history, U2 from across the sea would come to harass us almost every once in a while.
As a target of special attention, any abnormal building in Factory 221 will be strictly guarded.
Therefore, for the theory department, the lower profile the better.
Immediately afterwards.
Lao Guo quickly took Xu Yun to a workshop that seemed ordinary even among the many 'iron boxes', and knocked on the door lightly a few times.
Winter——, winter winter winter.
It's obvious that one is long and three are short.
It took about a few seconds.
The peephole of the workshop door was opened a small crack, and a pair of eyes that looked very alert appeared behind the door.
After seeing Lao Guo's face clearly.
Crunch——
The door was opened from the inside.
A man in civilian clothes with a serious expression appeared, and to his left stood two soldiers holding semi-automatic rifles:
"Director Guo, you are here."
"Well, there are some things here in Guangda that I need to take care of."
Lao Guo nodded towards him, then pointed to Xu Yun beside him and said:
"Lao Zhou, you don't need any more introduction from me, right?"
The middle-aged man named Lao Zhou was short and stern, and his face was even more serious than the Cheng Kaijia Xu Yun had seen before...or rather smelly.
Xu Yun had never seen this person at the base's executive meeting, but judging from the way Lao Guo spoke, the reason why this person did not appear at the meeting was probably not because he was not high enough, but because of the need for confidentiality.
Then Lao Zhou glanced at Xu Yun.
Just when Xu Yun thought Lao Zhou would let him go, Lao Zhou suddenly stretched out his hand and tore open a small scar on Xu Yun's face.
A severe pain instantly made Xu Yun grimace:
"Fuck, it hurts, it hurts, it hurts..."
However, Lao Zhou carefully observed the slightly bleeding wound under the scar, and then opened Xu Yun's pants and took a few glances.
After making sure everything is normal and not fake.
He just nodded in relief and moved away:
"No problem, you can go in - Comrade Han Li, confidentiality regulations require it, please forgive me."
Xu Yun twitched the corners of his mouth twice:
"Understand, understand..."
Then under the guidance of Lao Guo.
Xu Yun finally entered the workshop.
This workshop was about the same size as an indoor gymnasium in an ordinary high school in later generations. From the outside, it looked like a warehouse with a medium volume, but its internal structure should be very simple.
However, after entering the workshop, Xu Yun discovered that this workshop was far from as simple as it seemed.
because.....
What appeared in front of Xu Yun after entering the workshop was not the upward stairs or the level floor, but...
A downward walkway.
That's right, the downward walkway.
In other words.
The basement of this workshop is empty.
Perhaps to facilitate the transportation of some materials or equipment, there is a very primitive elevator - or should we call it a lifting platform - installed on the edge of the corridor.
Then with the help of this thing, Xu Yun and Lao Guo came to...
basement one.
This underground facility has a painting style that is very different from the current period. The walls are painted with a smooth soil layer that Xu Yun cannot recognize, and the floor is a standard self-leveling floor.
If it weren't for the fact that the lighting facilities still use some old tungsten filament bulbs, Xu Yun would even feel like he has traveled back to 2023.
Then Lao Guo led Xu Yun through many twists and turns, and finally came to a house numbered [Special 01].
This time.
Lao Guo did not knock on the door with a code of a certain frequency as he did before entering the workshop, but opened the door directly and walked in.
As the door opens.
The next second.
A noisy voice came into Xu Yun's ears:
The first is the crackling sound of the abacus. This irregular but crisp sound is conspicuous everywhere.
When he heard the sound of abacus calculations, Xu Yun suddenly remembered something.
In 2023, the year he traveled through, you can often see a saying on the Internet:
The abacus did not play much role in the development of nuclear weapons. It was just to highlight the hardships of some "heroes", which is a movie expression technique.
This statement is simply ridiculous.
Whether it is in the memoirs of current elders such as Yu Min or Qian Wushi, or in official documentaries, the abacus can be seen mentioned repeatedly.
According to Mr. Yu’s memories.
Their light-core team of more than 30 people alone has consumed more than 200 abacus in five years.
True.
It is very troublesome to use an abacus to calculate partial differential equations and various functions, but the question is, do they have any options in this era?
The computing power of Computer 103 is only over 10,000 per second, and there are only 47 hand-operated computers shared by more than 5,000 scientific researchers in the entire base. What can we use without an abacus?
It's not that the rabbits are seeking the far away, it's just that this was the only condition at that time.
After the rabbits have finally worked hard to achieve results, the result will be deceived into someone's mouth. Isn't this the most ridiculous thing in the world?
Now that some people on the Internet have discovered that the existence of the atomic bomb cannot be erased, they have begun to try their best to negate the hard work of those predecessors. A certain Douyin account even made remarks like "Rabbit had the most powerful computer in the world at the time."
Probably in a few years.
There may be comments on the Internet that the rabbits built nuclear weapons while eating big fish and meat while plugging in the RTX 4080. What's outrageous is that some people still think you believe this statement?
His eyes returned to reality.
Besides the sound of abacus.
Then came various discussions:
"Lao Hou, I don't have any paper here, can you lend me some?"
"Brother Cheng, can you help me see if there is anything wrong with my result?"
"Do you want to go to the toilet together?"
"Gong Liu, is this range too big? I think 0.3324 should be enough."
There were about thirty people in this room, and the area was about the same size as two ordinary high school classrooms in later generations.
This is actually the second time Xu Yun has seen a group discussion - the last time was in the Zhuxian Sword group to calculate the waverider. In fact, Xu Yun has always had a question in his mind that is quite puzzling:
In such a noisy environment, are the calculation results really error-free?
At least Xu Yun had very high requirements for the surrounding environment when he was calculating the questions.
In some cases, he even wears 3M earmuffs, although these are not friendly to people with big heads...
But as of now.
This kind of environment is not a big problem for the predecessors of this era, and some people even like this kind of noise.
And in this noisy atmosphere.
There is one location that stands out:
At this moment.
A large group of people were gathered around a table located at the back right of the room, discussing something intensely with each other.
It is easy to tell from the sparse hair on their foreheads that this must be a discussion between strong men.
Then Lao Guo closed the door and led Xu Yun straight to where the group of people were.
As the distance gets closer.
Some previously inaudible conversations gradually became clearer:
"Lao Hua, please calm down. The neutron angular flux density cannot be so low. You must have calculated it wrong somewhere."
"It's not me who's excited, it's you who are targeting me! My answer is obviously correct!"
"Lao Hua, we have known each other for so many years, who would target you? We are obviously discussing mathematical problems, and the values of even-parity spherical harmonics are clearly written on the document..."
"Yes, Lao Hua, you are just too sensitive. Yesterday you said you wanted your son to marry my daughter..."
"Don't talk about this shit, let's just talk about it - if you bring this up again, do you believe that I will have my son mutilated when I get back?"
"????"
all in all.
When Xu Yun and Lao Guo arrived at the scene, what appeared in front of them was this scene:
About ten researchers gathered around the table and were clearly divided into two groups: left and right. Lu Guangda was surrounded in the circle with a look of helplessness on his face.
See this situation.
Lao Guo immediately called out Lu Guangda’s name:
"Guangda!"
Lu Guangda was looking at a document in front of him with his eyebrows furrowed, but he immediately raised his head after hearing this.
After seeing Lao Guo and Xu Yun, he was slightly startled at first, then his eyes lit up and he said with great joy:
"Lao Guo, Comrade Han Li! Oh my, you are here!"
Then under the gaze of everyone.
Lao Guo pushed Xu Yun to the table like he was pushing a shopping cart in the supermarket, and nodded his chin at the manuscript paper in front of Lu Guangda:
"Guangda, what's wrong?"
Previously, due to the need for confidentiality, Lu Guangda only sent someone to inform Lao Guo in a concise way that the theory team had encountered some situations, which were roughly related to neutron transport, but no matter how much Lao Guo did, he would not understand.
Lu Guangda sighed after hearing this and explained to Lao Guo:
"Lao Guo, do you still remember the set of foreign language journals you brought back before?"
"Inside is a document that Comrade Nagatomo brought from the Los Alamos National Laboratory. In addition to some important parameters, the document also describes a stationary critical state model."
Lao Guo nodded with a heavy face:
"of course I remember."
How could he have forgotten this?
After all, this document is a top-secret document that his best friend paid for with his life...
Then Lu Guangda paused and continued:
"After we translated this document, we immediately conducted whole-group study and discussion, and we did produce very good theoretical results not long ago."
"These theoretical results have greatly boosted our research efficiency, and many areas that were previously stagnant have begun to loosen up."
"It was only during the subsequent calculation of neutron flux density that we suddenly discovered a situation..."
Speaking of which.
Lu Guangda raised his head and glanced at Lao Guo, then picked up a document from the table:
"Based on our subsequent derivative calculations of the model, we found that there are obvious anomalies in some calculation results."
Lao Guo frowned when he heard this, took the document and read it.
after awhile.
He couldn't help but let out a whisper from the wings of his nose:
"Well?"
Neutron transport equation.
This is a very, very important module in the development process of the atomic bomb.
My classmates who were atomic bombs in their previous lives should all know this.
The probability of neutron-nuclear collision during a nuclear explosion is a very complex process - both in application and calculation.
The atomic bomb initially bombards and then explodes neutrons.
During the propagation process, neutrons encounter new nuclei and then emit new neutrons.
These neutrons will randomly move in different directions, collide again, and so on...
Such a round-by-round process must be mathematically accurate to the motion state of the neutrons during each round.
To describe it in terms it goes like this:
A neutron that initially has a certain energy and a certain direction of motion at a certain location in the pile will later move to another position in the pile and appear with another energy and another direction of motion.
This motion trajectory is represented by a set of mathematical equations, which is the neutron transport equation.
But the problem is....
The energy distribution of the neutrons produced after the chain reaction is very wide, and multiple groups of Boltzmann equations need to be solved, and this thing has no analytical solution.
so what.
Numerical solutions can only be obtained through various calculation methods after discretization. The shape of the nuclear fuel in nuclear weapons is also relatively complex, so the solution is more difficult.
Computers of later generations have strong computing power, and this problem can be calculated directly using Monte Carlo calculations.
But in this era, we can only solve the neutron transport equation of a single group by hand, which is very troublesome.
But you can’t do it if you don’t solve this problem, because without a specific solution, many application operations will be impossible.
For example, where is the control rod inserted?
How does highly enriched uranium reach critical volume?
What is the proper placement of fuel?
Without specific numerical values, these things cannot be achieved.
Therefore, when he received the documents from Los Alamos National Laboratory, Lao Guo was both sad and happy.
The sadness is because the process of obtaining this document was too bumpy, and more than one comrade-in-arms died during the escort.
I am happy because with this document, many difficulties should be solved smoothly.
But now it seems...
This matter is far from that simple.
For example, the calculation paper in his hand is a very standard calculation process of general numerical values.
That is, when the mean free path of the particle is very small.
Under diffusion conditions, the discrete ordinate is solved through the optical thick cell cavity... which is the value of a module in the application of atomic bombs.
The form of the transport equation is as follows:
ut+b??u=0
Here u=(x,t),
Among them, the time variable: t≥0.,
Spatial variable: x=(x1,...,xn)∈Rn.
Side-by-side vector: b=(b1,...,bn)∈Rn, this is a fixed vector..
Then on the boundary Γ:Rn×{t=0}, given the initial value, g:Rn→R.
Observing the above equation, it is not difficult to find that the derivative of u along a certain direction is 0.
At this time, fix an arbitrary point (x, t) and define z(s)=u(x+sb,t+s), s∈R.
Using the equation at the beginning we can get an expression:
dz(s)ds=b??u(x+sb,t+s)+ut(x+sb,t+s)?1=0.
It is not difficult to see from this expression.
For each point (x, t), u is a constant on the straight line passing through (x, t) and in the direction (b, 1), which is actually its initial value at time t=0.
Then adding a value-added term to the diffusion equation, we can easily get a result in which the exponential term is a positive number of e.
At least according to Lao Guo's mathematical level, there is no obvious abnormality in this derivation process.
But when he saw the result, he was instantly stunned.
I only see this moment.
In the final summation of the infinite term series, what is shown is a result in which the exponential term is the negative number of e!
See here.
Lao Guo suddenly raised his head and looked at Lu Guangda opposite.
Lu Guangda helplessly spread his hands towards him and sighed:
"See, isn't it strange?"
Lao Guo pondered for a moment, continued to flip through the manuscript in his hand a few times, and asked:
"Guangda, is it possible that there was a problem with the earlier data calculation?"
"Impossible, absolutely impossible!"
Lao Guo just finished speaking.
The middle-aged man who had been fighting with everyone before became excited again:
"At first I thought there was something wrong with the front-end data, so I led a team to recheck it three times! It even took an hour of calculation time for the capital's computer!"
"But no matter how you calculate it, all the prerequisite conditions meet the requirements of the simulation in the Los Alamos National Laboratory documents."
"So there must be something wrong with the translations of your three groups! Some words were translated into another concept!"
"Fuck your mother!"
I heard these words from a middle-aged man.
The other short middle-aged man... who was estimated to be only about 1.5 meters tall couldn't help it. After all, there was an 'outsider' like Lao Guo present at this time, and some face had to be fought for:
"I studied in England, France and the United States, and my major was applied mathematics. You can't be wrong with this kind of terminology even if you close your eyes!"
"Stop speaking in vernacular, you can trust Yada when translated into Wenzhou dialect!"
"Then what do you think is going on?"
"I'm asking you this damn thing!"
Looking back over so long a time.
This was the first time Xu Yun saw such heated differences of opinion in the base.
Although Lao Guo and Lu Guangda reacted quickly and quickly asked other members of the group to take them away to calm down.
But the atmosphere of the entire scene has dropped significantly.
See this situation.
Xu Yun on the side couldn't help but blinked and said to Lao Guo:
"Guo Gong, can you show me the calculation paper?"
Lao Guo nodded and handed the manuscript paper to Xu Yun.
The manuscript paper was about 0.5 centimeters thick, but Xu Yun's hands had regained some strength now, so he took the manuscript paper without much effort.
"...."
Although the concept of neutron transport is a related category of nuclear engineering, its essence overlaps with Xu Yun's physical direction.
So it's very fast.
Xu Yun finished reading the calculation paper and had a vague idea in his mind.
Sure enough...
Then he took a deep breath and said to Lao Guo:
"Guo Gong, I've finished reading."
At this time, Lao Guo was writing and doing calculations, trying to find out the problem. Hearing this, he asked without raising his head:
"Oh? How's it going? Do you have any ideas?"
Xu Yun pondered for a moment and suddenly said:
"Guo Gong, I wonder if you have considered this possibility?"
"What's possible?"
"The problem is actually not the translation or calculation process, but... the Los Alamos National Laboratory document itself?"
"..."
Hear this.
Lao Guo suddenly stopped writing.
After a while.
He suddenly raised his head and looked at Xu Yun, his expression full of astonishment:
"Xiao Han, what are you talking about?"
"You have to know that there is no possibility that this document was intentionally leaked to us - the information in the first half of it helped us solve many theoretical problems."
"That is to say, this is the result of the development of the top team across the sea, and no one has tampered with it."
"And the person who made this model was Norris Bradbury, the director of Los Alamos National Laboratory, the absolute core of the Manhattan Project!"
"He is an expert and authority in the field of nuclear weapons, second only to Oppenheimer - in the Trinity nuclear test across the sea, Bradbury was also the person in charge of the final assembly."
"Xiao Han, do you understand what I mean?"
"I understand, it's an authoritative conclusion."
Xu Yun nodded slightly, then spread his hands:
“But what if the authority itself is wrong?”
............
Note:
I roughly know the reason for the previous beef. The main reason is that I didn’t use kitchen paper to absorb the blood. After using kitchen paper, the taste is completely different.
As for the students who said I was cheated, please explain. I bought beef from Mayura. It may be expensive but the quality is guaranteed, so I don’t think I was cheated. I only entertain friends once in a while and I don’t eat it every day. This kind of standard
I haven't been entertained once in several years.
It's the end of the month. Please give me some monthly tickets.
