Chapter 466 PNP? Phone call at the closing ceremony of the International Congress of Mathematicians

Chapter 466 P≠NP? Phone call at the closing ceremony of the International Congress of Mathematicians

Research on lithium-sulfur batteries has also begun, and since the main materials studied are only solid electrolyte materials, the research task has become relatively easier.

As a very ideal new battery among lithium batteries, lithium-sulfur batteries have an order of magnitude advantage in energy density compared to ordinary batteries.

But of course, lithium-sulfur batteries are still a product of the laboratory. With current technology, they can only be tested in test tubes.

This is because of its several shortcomings.

The first is that the intermediate discharge products of lithium-sulfur batteries will dissolve into the organic electrolyte, thus affecting the performance of the electrolyte and ultimately the overall performance of the battery.

Secondly, when elemental sulfur is used as the positive electrode of a battery, some final products produced during the reaction will affect the performance of the battery, and in severe cases, may even directly cause damage to the battery.

Finally, there is a problem called lithium dendrites. As an active material, the metallic lithium in the negative electrode will undergo physical changes during the charge and discharge process. When the lithium ions are reduced to metallic lithium on the back, each lithium atom It is possible that lithium dendrites will form on the surface of metallic lithium, and these lithium dendrites may pierce the separators of the positive and negative electrodes and then directly contact the positive electrode.

Once the positive and negative electrodes come into contact, it will cause a short circuit problem. After the short circuit, the temperature of the battery rises sharply, which will eventually lead to combustion, or even more serious, an explosion.

It is precisely because of these rather thorny problems that lithium-sulfur batteries are still only a laboratory technology and have never been realized.

However, if solid electrolytes are used, most of these problems can be solved.

For example, the first question is that the solid electrolyte is not a liquid, so naturally there is no problem of dissolution, so this problem is not a problem.

Another example is the problem of lithium dendrites. Lithium dendrites are an inevitable problem in lithium batteries. In most of the current lithium-ion batteries, battery manufacturers have made many plans to solve the problem of lithium-ion batteries. Therefore, there are basically very few cases of dangerous accidents caused by lithium dendrites.

However, although there are very few, they still exist, but lithium dendrites will also be helpless when facing solid electrolytes. After all, the main problem of lithium dendrites is that the positive and negative electrodes are connected to cause a short circuit, and then the temperature rises sharply. High, but now solid electrolytes are used. No matter how powerful the lithium dendrites are, can they still directly pierce the entire solid electrolyte?

Therefore, the problems existing in solid electrolytes are also solved.

The remaining problems will have relatively small impact. Although they are also problems to be solved, compared with the role of solid electrolytes, they can be solved at the end.

Therefore, for Lin Xiao, solving the problem of solid electrolytes first is the most important thing.

…

Lithium-sulfur batteries are only one aspect. While Lin Xiao was studying this technology, he did not forget the problems of the quantum computer control model given to him by Academician Pang Wei.

After so long research, he finally got stuck on a problem.

"How to judge whether it expresses 1 or 0 during this moment?"

Lin Xiao frowned. He had made no progress on this issue for a whole month.

Of course, it’s just that there has been no progress for a month. For other researchers, it is completely common for other researchers to have no progress on a problem for a month.

Even more, even one or two years is a very common thing, not to mention some people who are studying world-class problems, it is not impossible to do it for ten years.

However, for Lin Xiao, it was still a bit difficult for him to make no progress in a month.

Of course, this also shows that the difficulty of this problem is high enough.

And this can also bring him more challenges.

"Perhaps I should spread my thoughts?"

Lin Xiao began to think in his mind.

"What if the quantum state representing 1 is expressed as a function, and the quantum state representing 0 is expressed as another function, and then the chip's recognition ability is used to identify it?"

Suddenly, an idea flashed through his mind.

"By the way...P=NP?!"

It's like he used the principle of the P=NP problem to construct a program, and then used this program to determine the relationship between gravitons and the theory of relativity.

"If we use the same method, we might be able to solve this problem."

There was a moment of thought in his eyes.

Then, there was movement in his eyes, and then he took out a pen and started writing.

Intuition told him that this method was feasible, but how to solve this problem still required mathematical inference.

Just like that, a week later, he looked at a function he got with great surprise.

Of course, this function has nothing to do with what he wants to create. At best, it can only be regarded as an intermediate product. However, the meaning of this intermediate product is unusual.

"Is this a one-way function?"

He frowned, looking at this function, and couldn't help but think about it.

If this is really the case, then he may have accidentally solved another of the seven millennium problems.

Of course, this "solution" does not refer to proof, but to falsification.

He will falsify that P is not equal to NP, that is, for the P problem, it cannot be completely equivalent to the NP problem.

P is the complexity class P, which is all problems that can be solved by a deterministic Turing machine in polynomial time; and class NP consists of all decision problems that can verify whether its solution is correct in polynomial time.

Once it can be proven that P=NP, all problems in the world will become simpler, just like if nonlinearity and linearity can be unified.

However, in the past, most scientists did not believe that P could be equal to NP, especially for some cryptography experts. After all, once P = NP, the cryptography building would collapse, because P = NP can make Any password becomes difficult to crack, and it only needs to be handed over to the computer for calculation.

However, there are still great difficulties in solving this problem, whether it is proof or falsification. And because of the significance of this problem, it was selected as one of the seven millennium problems.

Among the methods of falsification, one method is to find a one-way function.

A one-way function means that for each input, the function value is easy to calculate; but for a random function value, it is more difficult to calculate the corresponding input.

That is to say, in f(x)=y, given a value of x, we can easily get the value of y, but if a value of y is given, it is difficult for us to calculate the value of x in reverse.

This is completely inconsistent with the situation when p=np, and naturally this question is falsified.

In other words, the one-way function is like a special solution. As long as one is found, this millennium problem can be solved directly.

However, at this moment, Lin Xiao had no idea that he was just trying to find a model that could control a quantum computer, but he inadvertently found this thing.

He even felt a little unreal for a moment.

But then, the system's voice suddenly sounded, telling him that this was very real.

"Congratulations to the host, I successfully found a one-way function and proved that P is not equal to NP..."

The sound of the system made Lin Xiao stunned.

The system actually recognized it?

However, as soon as he thought this, the system's next words made his heart skip a beat.

"However, if the host thinks this problem is over, then please think about it, do you really think so?"

"Reward: 5000 math experience points, 3000 informatics experience points, 50 truth points."

Lin Xiao felt very confused and puzzled when he heard the system's words.

Now that it has been explained that the function he accidentally found is a one-way function, why do you need to say this again?

"Is that really what I think?"

"Does the system mean that it can still prove this P=NP?"

He felt sincerely puzzled.

Prove a falsification problem?

Where to start from?

Just when this confusion arose in his heart, his cell phone suddenly rang.

After regaining consciousness for the moment, he picked up his phone and took a look.

"Huh? Is this Terence Tao's phone number?"

Why did Terence Tao suddenly want to call him?

The International Congress of Mathematicians should be being held recently. Terence Tao should be at the International Congress of Mathematicians now. How come you still have time to come see him?

But he remembered again that today seems to be the last day of this year's International Congress of Mathematicians. Now this time seems to be the time for the closing ceremony?

This made him even more confused.

Then he answered the phone and said, "Hey, Tao, why are you suddenly looking for me? If I remember correctly, you should be attending the closing ceremony of the Mathematicians Conference, right?"

Then Terence Tao's voice came from the other side.

"Haha! Lin, yes, I am attending the closing ceremony of the Mathematicians Conference now. Of course, it is precisely because of this that I have to make this call to you."

After hearing Tao Zhexuan's words, Lin Xiao suddenly felt even more confused.

"What's the meaning?"

"Haha, I'll send you a video call invitation now. You'll know when the time comes."

"This...well, I want to see what you are doing."

Although I don’t know what Terence Tao’s intention is, since he said so, let’s take a look.

Soon afterwards, Tao Zhexuan sent him a video invitation.

Lin Xiao clicked to accept the invitation, and then entered the video screen.

As the video screen opened, Lin Xiao was stunned when he saw the scene on Tao Zhexuan's side.

Because in the video, Tao Zhexuan is clearly standing on the stage, and behind him is the audience.

I saw thousands of mathematicians and mathematics enthusiasts or practitioners attending the conference, all sitting in their seats and waving to him.

At the same time, there were voices greeting him one after another.

"Hi! Professor Lin!"

"Lin! Long time no see!"

"Professor Lin!"

…

Although the sound was relatively noisy, Lin Xiao could still hear what they were saying.

He was in a daze for a moment and said, "Uh... hello, everyone?"

Then he quickly asked Terence Tao: "Tao, what's going on?"

Tao Zhexuan smiled and finally explained: "This year's Mathematicians Conference has finally become a little dull without you. There are no more reports that shock the mathematics world like the ones you often bring to us."

"But because of this, we all miss you very much. Although for some reasons you are not able to appear here at this conference and discuss mathematics with us, we all believe that there will always be problems solved. That day.”

“The world of mathematics is family and we all miss you.”

After Terence Tao finished speaking, people in the audience shouted: "Lin! We all miss you."

Seeing this, Lin Xiao couldn't help but feel moved. He never expected that Tao Zhexuan would suddenly call him because of this incident.

He laughed and said, "Thank you everyone. I also miss you all very much. I miss the discussions with many friends at the two previous conferences."

"Of course, at least for now, I still participate in this conference in this way."

The mathematicians at the venue all laughed, and at this time Terence Tao also joked: "Hey, if this counts, you haven't brought us some surprising results yet! This is equivalent to breaking the You have lost your past habits!"

"There are so many surprising results!"

Lin Xiao suddenly couldn't laugh or cry.

However, at this moment, he hesitated for a moment and said, "Huh? It seems, it's not gone?"

The manuscript is gone. There are only 8,600 words in these two chapters, ╮(╯﹏╰)╭