E=mc^2

"First, before I explain to you why chakra still follows the conservation of mass and energy, I must tell you about the relationship between mass and energy."

"E=mc^2, this formula can be said to be quite famous. It reveals the relationship between mass and energy."

"Back in the day, I was somewhat dismissive when I first saw this formula. My thinking at the time was very childish. It's just that the dimensions on both sides of the equal sign are the same, who couldn't figure that out?" Chuanhe said with some emotion.

"But after I understood what energy was, I didn't think that way anymore. Do you remember how I explained energy to you before?"

"I compared matter to equipment, and energy to equipment attributes."

"Real, existing matter is converted into energy that does not exist in a real sense. To explain it with a term that most people in this world can understand."

"That term is—the conversion between the virtual and the real."

His father's words startled Hui. Indeed, abstract concepts were not easy to grasp, but the term "conversion between the virtual and the real" made him understand much more the moment he heard it.

"What people talk about most regarding this formula is not its physical meaning. Rather, it is its destructive power that has made it famous."

"Heh, destruction, how ironic."

"E=mc^2."

"The standard unit of mass is the kilogram."

"Do you know what kind of explosion it would be if one kilogram of matter were completely converted into energy?"

"About 1,400 Little Boys."

"For each one, the effective kill radius for a Jonin is probably less than a kilometer. But it could level buildings across an area the size of the entire Konoha village."

"You don't even need a kilogram; just one gram could blow the whole of Konoha into the sky."

"Matter is not such a simple thing, Hui. The energy contained within it is beyond your imagination."

"But releasing this energy is extremely difficult; this weapon is also an ultimate weapon where I come from. Even then, it can only convert a few thousandths of the matter."

Hui listened to his father's words in silence. Ever since his father began teaching him theory, he slowly discovered that his father did not seem to be from this village.

Could he be a spy from another ninja village? But he didn't care; what did it matter if he were a spy? He was the only family he had left.

All he needed to do was become strong before all of this arrived—stronger than anyone else. Only then could he protect his father.

However, Hui had recently discovered that his father didn't seem to have any malice toward the clan. Thus, he also began to re-examine his own clansmen.

This was also why he eventually decided to become friends with Sasuke.

"Perhaps you have been wondering why I only teach you methods for quick success."

"Because my intention was never for you to become a ninja. Attending the Ninja Academy was also at your request, Hui. Since this is your dream, I will support it to the end."

"Heh, humans. Our attainments in the path of destruction are always higher than those in creation. I am no exception."

"I once yearned to become a powerful ninja like Uchiha Madara, but things did not go as planned. By the time I had the ability to pick up that dream again, I no longer had the capacity for it. Now, my combat style has completely solidified."

Hui was curious; listening to his father, it seemed his combat style was completely different from that of a ninja. Which ninja village could have such a person?

"Your life has only just begun, Hui. You have plenty of time to consider what kind of person you want to become and what goals you want to achieve. No matter what choice you make, as long as it does not violate my principles, your father will support you."

"I've digressed. Sigh, it's easy to worry too much as one gets older."

"Where was I? Oh, right. Before we continue with the subsequent lessons, let me introduce you to two concepts."

"Antimatter and negative mass matter."

"These two things are completely different, Hui; do not confuse them."

"Antimatter... do you remember the atomic theory I told you about? Let's use electrons as an analogy; the antimatter of an electron is a positron. It carries a positive charge of equal absolute value."

"If such a positron and an electron come into contact."

"Annihilation will occur."

"All of the mass will be converted into energy, just like in this formula."

Hui raised his doubt: "Father, can annihilation reactions only occur with this kind of one-to-one corresponding antimatter?"

Chuanhe said: "Hui, you guessed correctly. Not all antimatter will directly annihilate upon contact with matter. It must be a one-to-one correspondence."

"But I actually have many doubts about this conclusion myself, but because the antimatter in my hands is extremely scarce, I haven't been able to conduct such experiments for the time being."

Hui's body trembled. Antimatter? Explosion? Konoha? Was his father planning to destroy the entire village?

Chuanhe naturally noticed Hui's little thoughts.

"Rest assured, Hui. Your father is a kind-hearted person who cannot bear to see the suffering of the world. Heh, or rather, I only know how to escape from suffering. I am not a terrorist, and antimatter is just one of my research topics. In fact, one could say that due to the difficulty of manufacturing it, it has almost no practical value."

"Perhaps when I completely crack how non-attribute chakra is transformed into attribute chakra similar to physical matter, I will be able to mass-produce antimatter."

"I've digressed again. Next, let me tell you what negative mass matter is."

"Just as the name suggests, it is matter with negative mass. This is a very counter-intuitive substance."

"If normal matter falls toward the ground due to gravity, negative mass matter will fly toward the sky due to its properties."

Hui felt his brain couldn't keep up again. Antimatter, he could understand a little. What on earth was this negative mass? Did such a strange thing really exist in the world?

Looking at Hui, whose face was all scrunched up, Chuanhe said: "I confirmed its existence based on a conclusion in my memory. I remember an experiment that proved the existence of negative energy. Then, according to this mass-energy equation, doesn't that prove the existence of negative mass?"

(Note: Such a correspondence does not exist in the real world; this is a misunderstanding on Chuanhe's part.)

"Do you have any questions now, Hui?"

"Father, according to what you just said, would negative mass matter and positive mass matter annihilate upon contact?" Hui voiced his confusion.

"That, how should I put it? In all likelihood, no. But to confirm this conclusion, experiments are required. It is a pity that I have not obtained any negative mass yet."

"Antimatter is antimatter, and negative mass is negative mass; they are not the same thing. Even antimatter will still fall normally under the influence of gravity. That is the difference between them."

Hui nodded to show he understood.

"Then, Hui, all the preliminary preparations are complete. Originally, this should have been the content of the third lesson. But since you have already grasped this much, it is just as well to follow the momentum."

As he spoke, Chuanhe stood up. He looked around the surroundings, then closed his eyes to weave hand seals, releasing a ninjutsu that Hui did not recognize.

Hui felt an invisible wave of chakra emanate from his father's body and spread rapidly in all directions.

Judging by this, it must be a sensory ninjutsu, Hui thought to himself.