Chapter 1: Welcome To 1960
If life could be chosen again, Lin Ran would absolutely not choose to spend the last day of 2019 stargazing at Cherry Spring National Park.
He was just trying to find a spot around his pitched tent to relieve his urgent need to urinate, but he encountered a strange light gate, and his excessive curiosity led him to approach and see what it was.
Then?
Then there was no then.
When he regained consciousness again, everything he could see was pitch black.
Lin Ran did not suspect that he had gone blind, because he had not only lost his vision.
Hearing, touch, taste, and smell had also disappeared along with it.
The disappearance of the five senses made one shudder.
No matter how he tried to open his eyes, he could not feel the existence of his gaze.
The surroundings were only empty darkness, and silence and emptiness gradually emerged in his heart.
No! There was something; Lin Ran could feel that something indescribable in the distance was continuously devouring the darkness.
Although he did not know what it was, his intuition was telling him that once the darkness was completely devoured, his consciousness would also be devoured along with it.
Countless thoughts flashed through his mind, “Was I stargazing and the stars were watching me? Have I been kidnapped by aliens?”
Lin Ran already regretted it; if he had known it would be like this, even if it was boring to stay in his rental apartment or read literature in the library to spend the last day of 2019, it would be much better than his current situation.
Consciousness disappearing meant, at best, becoming a vegetable, at worst, death.
From the initial mind full of distractions, as time passed, the distractions in his brain were quickly disappearing, leaving only endless pain and torment. Lin Ran could fully understand why solitary confinement was top-tier torture.
Whether it was the environment he was in or the crisis of his consciousness about to disappear, both were enough to make Lin Ran teeter on the edge of collapse.
“No! I can’t just die like this; if I’m done for, I feel my mom won’t be able to live on either.” As the only child in a single-parent family, Lin Ran knew very well what he meant to his mother.
“No, consciousness cannot stop it from spreading!”
“Thinking doesn’t work either!”
“Exactly how can I stop it from spreading?”
Lin Ran was terrified inside; he did not even need to wait for it to devour his consciousness—his own negative emotions were enough to overwhelm him.
“No, I have to find something to do; otherwise, I’ll go mad or become an idiot.” Lin Ran thought.
As an outstanding graduate of the Aerospace Engineering Major at Jiaoda School of Aeronautics and Astronautics, and currently a PhD student in the computer field at Stony Brook University, for Lin Ran, finding something to do meant pulling out the knowledge in his mind to review it.
“Using Graph AI to solve various problems, including partial differential equations, bioinformatics, quantum physics, materials science, and more.” A computer science PhD is an enormously vast field, and Graph AI is a new branch under this colossus.
Lin Ran actually had a strong interest in aerospace; as for why he did not choose it, it was because a Chinese person fundamentally could not apply for projects in the America aerospace field, let alone a PhD with scholarship.
So in the end, for the sake of life, he gave up his ideals and the distant horizon; a computer science PhD, whether staying in America or returning to China, had prospects and expectations far exceeding working in the aerospace field in China.
It was just that the Graph AI direction was a huge pit, which he had not anticipated.
“Design and Manufacturing, Automatic Control Principle, Aerodynamics, Engineering Thermodynamics, Comprehensive Russian Language, Aircraft Design”—these were all required courses in Lin Ran’s major.
Correct, Russian Language was one too; even English was only in freshman year, while Russian Language spanned their freshman to junior years, three years.
From textbooks to the content during professors’ lectures to the exercises he had done, they all emerged one by one in his mind; compared to the topic he was working on now, the aerospace-related content was still better at calming his heart and offsetting some of the fear brought by the darkness.
“Functions, limits, derivatives, integrals, multivariable calculus”
“Mechanics, thermodynamics, electromagnetism, optics, modern physics.”
“History of Aerospace Development, Aircraft Types, Aerospace Engineering Principles.”
One course after another presented itself in Lin Ran’s consciousness; content that was almost forgotten was reawakened, and Lin Ran felt that if he had been this serious in the past, his GPA would absolutely not have been just top five in his year—it would have been solidly first in the year.
The past Russian Language courses that were arduous and dull became particularly interesting at this moment; even sitting in the front row of the classroom getting sprayed with the professor’s saliva, Lin Ran would be willing.
“I can only hope this will be ‘Vsyakaya beda–kluchshemu privodit.'”
This Russian Language sentence means “the blessing in disguise.”
After going through all his university courses from beginning to end, breaking them down and piecing them apart once, Lin Ran discovered that some strange changes were occurring in him.
More and more forgotten details from the past, fragments not noticed in class, were being awakened; his brain’s computational ability was growing stronger.
As the darkness was being devoured, it seemed his thinking was being tempered along with it.
However, the trend of the indescribable thing continuously spreading remained unchanged; he could even feel the chill, which was enough to indicate that it was approaching.
“If life really ends like this, dissipating in the ocean of knowledge seems not bad.”
If his brain in the past was just a vacuum tube computer, now it was at the level of a semiconductor supercomputer; high-order determinants, large-scale systems of linear equations, linear equation systems with parameters, etc.—these types of problems in linear mathematics that required massive computations, he could quickly derive the results purely by mental calculation.
Time thus cycled back and forth continuously in the process of pain, thinking, and recollection.
Lin Ran discovered that not only had his brain ability made significant progress, but his concentration, originally weakened by smartphones, had also made a qualitative leap; the duration he could sustain thinking about problems was getting longer, and the time he could enter flow state was getting longer.
“If I could return to the real world, I would absolutely be a top-tier genius!” Lin Ran thought, but the premise was being able to go back.
After shuffling and reorganizing the past content, Lin Ran finally refocused his attention on the topic he was currently working on: “Using artificial intelligence to solve N-S equations.”
The reason Graph AI was called a huge pit earlier was because this direction was very new—what it could do anything with also meant it could not do anything solidly.
After Professor Samuel’s team at the University of Washington published a paper titled “Data-driven discovery of partial differential equations” in 2017, AI solving equations began entering the public view.
Lin Ran thus jumped into this pit.
Professor Samuel had previously worked on artificial intelligence solving partial differential equations, and what he was doing was also artificial intelligence solving partial differential equations; it was just that N-S equations were in the top tier.
N-S equations, one of the top-tier problems in the field of mathematics, are mathematical problems that can stand alongside the Riemann Hypothesis and the Goldbach Conjecture.
If a general analytical solution to N-S equations could be found, aircraft design could find optimal shapes under various conditions, wind power generation would no longer be trash electricity, wind power generation could be compared to photovoltaics and nuclear power, and car shapes could achieve optimal aerodynamic effects.
Simply put, finding the general analytical solution to N-S equations would provide an optimal solution to all real-world application problems involving air, liquid, or solid flow.
Even if the Nobel Prize or Fields Medal was not awarded, scientists worldwide would collectively protest.
This was also one of the few top-tier mathematical problems that, once solved, could most significantly impact the real world.
However, what Lin Ran was doing sounded impressive—using artificial intelligence to solve N-S equations—but in reality, it was not about finding a general solution; it was just doing some minor work, finding solutions under specific conditions, with difficulty roughly equivalent to fishing a needle from the sea reduced to fishing a needle from a bowl.
“But now I only have my brain, no computer?”
Lin Ran used his limited advanced mathematics foundation to derive formulas in computational fluid dynamics.
From the numerical method finite difference method in textbooks, he derived high-order finite difference method, compact finite difference method, adaptive finite difference method.
From finite element method, he derived mixed finite element method, discontinuous finite element method, isogeometric analysis finite element method.
The instant he derived the results, Lin Ran felt the indescribable thing’s spreading slowing down, “Could it be that it’s by expanding the boundaries of knowledge to stop it from spreading?”
Then what conditions must be satisfied to completely eliminate it?
Could it really be completely solving N-S equations?
From finite volume method, he derived high-order finite volume method, unstructured finite volume method, dual time step finite volume method.
When the five senses were lost, mathematics became the only source of beauty.
Bit by bit advancing toward N-S equations:
“If assuming ideal flow on a two-dimensional plane, then by adding certain boundary conditions, I can obtain the exact velocity field and pressure field.”
“For viscous fluid laminar flow between circular pipes or parallel plates, an exact solution can be obtained where the flow velocity has a parabolic distribution.”
The devouring speed was continuously slowing, even retreating, and the chilling feeling was lightening.
From plane Couette flow to Poiseuille flow, from circular pipe Hagen–Poiseuille flow to Taylor flow between rotating concentric cylinders.
Sudden startup of flat plates or circular pipes, flow near oscillating flat plates or rotating disks, two-dimensional or axisymmetric stagnation point flow impinging on flat plates.
When fluid inertial forces are much greater than viscous forces, N-S equations can be split into two regions for solution. In the outer region, it is uniform flow; in the inner region, ignore the horizontal derivative terms of the viscous terms in N-S equations to obtain a similarity solution.
The exquisitely constructed mathematical edifice by predecessors, in the past Lin Ran could only glimpse a corner of it, but now he could not only see the full picture but also see what other mathematicians could not; he realized he truly might add a layer named N-S equations to the entire mathematical edifice.
Lin Ran was advancing bit by bit toward the general solution of N-S equations.
“How long has it been? It seems I’ve found the general exact analytical solution to N-S equations!”
After verifying the general solution with various N-S equations, Lin Ran felt he had really done it; just with a basic fluid mechanics textbook, to reach solving N-S equations—this was far more exaggerated than cultivating a true immortal with martial arts techniques, Lin Ran thought.
Although there were no big shots to verify, no public to witness together, no human world cheering for it, no Nobel honor crowning him, he still knew that by persistently tackling the ultimate problem through unprecedented thinking in endless ages, without becoming an idiot or losing sanity, his soul was cheering for him, his spirit was applauding him.
“Old Wang who taught me calculus, if he knew, would definitely feel this life has no regrets, having taught a student who solved N-S equation problems.”
Before he could be happy, the pitch black finally collapsed bit by bit, and a colorful world slowly emerged before his eyes.
“What the hell is this?”
Whether it was the vehicles whistling by on the road, the pedestrians’ attire around him, or the most eye-catching large “1960” on the crystal ball in front of him.
All told Lin Ran one precise piece of information: welcome to 1960.
“The neon ball marked ‘1960’ is 46.2 meters away from me; the temperature in the air now is about 15% higher than at Cherry Spring National Park where I was before; combining the sun’s direct angle, the approximate time point now, and the surrounding environment, I’m probably still within New York State.”
The classic red shape on the back and the telephone letters “TELEPHONE” told him this was a telephone booth.
The vehicles passing by in front of him were like in slow motion, every license plate number engraved in his mind.
Lin Ran felt that if a bullet were coming at him now, he could see through its trajectory and dodge the bullet.
Countless pieces of information exploded in his mind like fireworks one after another; the evolution of his brain and body was secondary—Lin Ran realized his greatest gain at this moment was: “Gate.”
“More precisely, I can travel between all the gates I’ve passed through; all gates are my anchors, and that white light circle created a gate to a 1960 parallel spacetime for me, which is this telephone booth behind me.”
“Now in 1960 I have only one gate, but in 2020 I have countless gates?”
The gates he had passed through in the past emerged one by one in Lin Ran’s mind.
In the cold wind of New York, Lin Ran gritted his teeth standing at the newsstand freeloading the day’s New York Times, trying to figure out the situation.
“In 1957, the Soviet Union successfully launched the world’s first artificial Earth satellite, Sputnik 1, marking humanity’s entry into the Space Age.”
“On January 1, 1958, the European Economic Community and the European Atomic Energy Community were formally established.”
“In 1958, Jack Kilby of Texas Instruments in America invented the integrated circuit.”
“Sir, 10 cents for a copy of the New York Times New Year’s special issue.”
Putting down the newspaper, continuing to stand on the residual snow in front of the newsstand, the billboard next to it showed a blonde woman puffing smoke, with the slogan below “Camel Cigarettes, doctors love them too!” half covered by snowflakes.
In the public telephone booth behind him, a young man in a coarse tweed suit was yelling into the microphone: “Those hicks in Houston don’t understand orbital calibration at all!”
Lin Ran turned back and saw the man with a silver NASA badge on his chest, the glass covered in fog.
By the time Lin Ran came back to his senses, he was already in the lobby of a coffee shop next to the telephone booth, with a cup of hot water on the table; the blonde blue-eyed waitress at the bar saw Lin Ran look up and gave him a friendly smile, and across from him sat the young man just from the telephone booth.
“Sir, you just mentioned orbital calibration; I think I can provide you with some help.”
