Interstellar arena

Along the way, Liu Fei chatted with this sloppy middle-aged man. In fact, most of them were middle-aged people talking, and Liu Fei was listening. Liu Fei paid more attention to the side of the road and kept passing by. He found that the atmosphere of war became stronger the further he went inside. Moreover, after going deep into the corridor, he could no longer see the police. They were all soldiers in military uniforms and holding weapons.

From the chat, Liu Fei had a general understanding of this middle-aged man.

The sloppy middle-aged man is a scientist, mainly engaged in physics research, and he is best at mechanics. Of course, judging from the complicated professional vocabulary he mentioned, his knowledge is quite complicated. For this kind of person, Liu Fei has never There is no lack of respect, and in addition to nodding to deal with it, I will occasionally answer a few questions.

"Oh, I forgot to introduce myself, everyone calls me Powell, how about you?"

"Liu Fei."

"Well, I have also done some research on armor structure and materials. If you have any questions, you can ask me, maybe I can answer some doubts for you." There are nearly a hundred people on the suspension vehicle, and only the middle-aged people are enthusiastic about Liu Fei. add.

"Liu Fei, he must ask you for something!" Xiao Qiang said with a wicked smile.

"why?"

"Think about it, there are so many people here, if he doesn't strike up a conversation, he will just get close to you, show courteousness for nothing, rape or steal, hehe! I guess this guy wants you to help him pay back the money... Liu Fei, this guy's tone is really It's quite big, ask a few questions, challenge him, kill his prestige..."

"How long is the lifespan of a proton, and how to understand it?"

"what……"

Powell was stunned and looked at Liu Fei speechless. This question raised by Liu Fei is a physical problem that has not been solved until now. People used to think that protons are different from neutrons, and they will never be broken into smaller particles. .This was taken as truth.In the 70s, however, theoretical physicists realized that the various theories they proposed for what might become a "grand unified theory"—a theory that brings together all the forces except gravity—implyed that the proton must be stable.Given enough time, and very occasionally, protons can split, by catching dying protons.For many years, experimenters have been watching the large tanks in the underground experimental space, waiting for the protons inside the atoms to die.But in the hundreds of years of monitoring so far, the death rate of protons is zero, which means that protons are either very stable, or they have a very long life-estimated at more than 10 billion billion million million million million million years.

Simply put, there is no definitive evidence for how long the proton is.

"...Well, you can change it, I'm just an ordinary physicist." Powell said with a sad face after staying for a few seconds.

"Why does the cosmological constant have its own value? Is it zero, or is it truly constant?" Liu Fei asked his own question again, which he has always wanted to know, because, according to the knowledge he has mastered, he The expansion of the universe is accelerating, and this expansion is related to the warp drive. In theory, the speed of the warp drive has surpassed the expansion speed of the universe. Liu Fei has imagined more than once, if he drives a spaceship with a warp drive, can he catch up to The end of cosmic expansion?

"Ahem... the universe should be expanding at a jumping speed. But that's not the case. There must be some mechanism suppressing this effect. If the universe is really supersymmetric, then the cosmological constant should be completely canceled out. But This symmetry - if it exists at all - seems to be broken. If the constant changes with time, the situation is more complicated... This problem is too complicated to explain for a while... Can you ask a more practical question?" Powell blushed, while the little glare brain in the dark croaked excitedly.

"The action mentioned in the third of Newton's three laws is always equal to the reaction in the opposite direction. That is to say, if the horse draws a cart, the cart will also use the same force to pull the horse. At this time, the cart should stop at the original place. Why does it move forward? The forces are equal, so why don’t they cancel each other out?” For a long time, Liu Fei was a little confused about the action force and reaction force. According to the third explanation of the three laws of mechanics, in When attacking the enemy, according to the third law, he also suffers an equal reaction, but the fact is that the enemy is injured, but he is fine, which obviously does not conform to the third law.

"Hehe... This question is very good. Everyone knows this law, and many people can apply it correctly, but few people can fully understand its meaning. Even for me, it took four years to really understand it. Understand it, at the beginning, I also doubted the reliability of this law, in fact, it is right, but we did not understand it correctly... The two forces do not cancel each other out, because they are loaded on different objects Reason: One force is applied to the horse, and the other is applied to the cart. The two forces are the same, and there is nothing wrong with it. But, is it said that the same force will always produce the same effect? ​​Can it be said that the same force can Can any object get the same speed? Does it mean that the force acting on an object has nothing to do with the object itself or the resistance of the object..."

"If you think about this, then the reason why the horse can still pull the cart even though the cart is pulling the horse backwards with the same amount of force can be understood. The force acting on the cart and the force acting on the horse The moment is equal; however, the cart has wheels and can move freely, while the horse is firmly on the ground, so the cart has to follow the horse. Think about it, if the cart does not have the same power as the horse If there is a reaction force, then there is no need for a horse, and the cart can be pulled away with a very small force, but in fact, to overcome the reaction force of the cart, a horse is still necessary..."

"Actually, changing Newton's third law 'action equals reaction' to 'action equals reaction' is easier for ordinary people to understand."

"Understood, it's like cutting muscle with a blade. No matter how sharp the blade is, it still needs a lot of force to pierce the skin and muscle, just like the reaction force of a horse-drawn cart."

Liu Fei nodded approvingly. Today, he finally figured out the problem that had puzzled him all this time, and he felt quite cheerful.

Powell never dreamed that Liu Fei asked for advice on the third law in order to achieve the highest state of the art of killing, because whether it is fighting with mechs or using Yuehua to fight, its essence is inseparable from action force and reaction force...

To put it simply, Caso's so-called art of killing is to maximize the force of action and reaction to the highest level.

"Hey, it's here. We may get along for a while. If you have any questions, just ask." Powell was enthusiastic.

"Ah."

At this time, the suspension car has arrived at a huge cabin. Above the cabin is a huge metal dome. The metal wall under the dome is densely packed with metal passages. There are rail cars shuttling in the passage non-stop. Some equipment and The armor is loaded into the rail car and the suspension car through some bulky cargo mechs. The whole cabin is in full swing. It is conceivable that the densely packed passages on the metal wall must extend in all directions like spider webs, and may reach any place in the space city...

"Old five, there are newcomers here, be gentle, there are contract workers!" After Liu Fei got out of the car, a policeman shouted into the busy crowd.

"Gentle fart, the space city is about to die, none of us can survive... Contract workers, contract workers... Damn contract workers, can't you find some experienced hands?!" A helmet, topless, The fat, greasy man came over cursing and spat at Liu Fei and the others with a look of contempt on his face.

"One hundred and three people, please sign." The policeman impatiently handed a paper document and a pen to the short fat man.