"No, it's not. Not so here, not in this part. Considering the uncertainty relationship between time and energy brought about by the uncertainty principle, when the time is short enough, the energy will fluctuate, which you have already understood. You have also mastered the calculations of the virtual process by which a photon becomes a virtual electron and positron pair in a very short time. However, you have some bad habits when calculating the probability amplitude of this virtual interaction process. If you look at this Feynman diagram, you can do the integration in this way. In this way, according to Feynman's rule, the expression of the corresponding matrix can be obtained relatively easily. ”

"Ah, I'm sorry, I was negligent."

"You also have to get used to the necessary techniques of using Feinmantu. Each line of the Feynman diagram corresponds to the distribution function of the virtual particles, and each vertex gives a factor that can be derived from the Lagrangian quantities of the interaction terms. Even energy, momentum, and spin can be seen clearly here, which is quite intuitive and useful tricks. ”

This is a completely confusing conversation for the uninitiated.

The two people in conversation aren't in the same room, not even in the same school district. This is not surprising, in today's advanced communication technology, the way of teaching has long transcended the constraints of geographical location.

What is surprising lies in the identities of both parties and the content of the lectures.

The one who guided was a middle-aged man, which was nothing special. The content of the lecture is quantum electrodynamics (QED). Although this part is a bit esoteric, there is still nothing too surprising about it.

What's really surprising is the identity of the person listening to the lecture.

It was a cute girl who hadn't even gone to middle school yet, and she was still very obviously immature.

The girl's name is Umihara Ukuno, and she is an applicant who is about to take the Tokiwadai entrance exam. Now,Two months before the start of the new school year in Gakuen City。

"Well, I know. It's just that I don't like renormalization sometimes. ”

"To be fair, I don't really like this somewhat self-deluding way of math, even more so than you. The more I thought about the significance of this damn addition, subtraction, and subtraction math in physics, the more disgusted I became. However, the accuracy of the renormalization is so high that there is no way to avoid its existence. We don't know why, but before the integration of physics is further completed, the existing physics tells us that nature is this strange thing. Maybe there's hope for string theory, but that's beyond our scope. And I have to advise you, even in the future, unless there is really no way, don't touch string theory casually, that thing even your teacher will look at it with a big ......head" (Author's note: In order to write these verses, I specially dragged out the medicine that I had been busy with half to death recently, and asked him to make up for my physics for a while, but this short paragraph is still so painfully written. What's worse is that there is foreshadowing in this paragraph, which is too cheating. ）

"Alright, done. Is that okay? ”

"So fast? Send it to me to show it. ”

"Hmm."

While talking to the other end, while tapping quickly on the keyboard, the girl sent the calculation she had just completed to the other party through the network.

Looking at the results of the calculations at hand, the other end of the network was silent for a moment.

"Haiyuan, I now understand why that Kurkov guy has to reserve an assistant position for you half a year in advance. If you wait until you enter the school and then arrange it for you, I am afraid that all the students who compete in the same period will be hit by you. ”

Closing the email, the middle-aged man on the other end of the network let out a long sigh.

"Huh? My teacher? What's going on? ”

Dome was a little surprised, she hadn't heard anything about it before.

"It's fine. It's just that your teacher asks us to reserve a seat for you as an assistant so that you can help him as soon as you get into school, that's all. I didn't tell you because I didn't think it was important. ”

"But I'm not a Tokiwadai student yet."

"That's right. But he's very confident, we can't beat him, and you know Kurkov's bad temper. ”

"Uh......h I suddenly feel so stressed......"

Dome was lying on the computer desk, pretending to be weak cutely.

"Haha, it shouldn't be too much of a problem for you."

"But......" Dome still buried her head on the keyboard, her beautiful voice was a lot duller, "It's still a little difficult to pass, the content of these entrance exams." ”

This action prevented her from seeing the slightly changed face of the middle-aged man on the monitor.

"And if you accidentally don't pass, isn't it a shame on the teacher's side? Suddenly hearing such a topic, it really added a lot of pressure, I don't know if it will affect the state......" I didn't know what I was talking about, but I didn't hear any response from the other side.

("Entrance Examination...... Damn, I'm going to have to clean up that guy when I turn around......")

From the headphones, it seemed that the middle-aged man's muttering was not very clear. Dome looked up, but her small chin rested on the computer desk. She's so cute.

"What's wrong?"

"No, I'm just thinking about something else." The middle-aged man hesitated for a moment and continued to ask, "I'm only in charge of quantum electrodynamics, and I don't know much about the rest." I'd like to confirm your overall impression, is it really 'a bit difficult' for you to pass these courses? ”

"Well, it's a bit of a difficult course, and it's really not careless."

"Is that so...... I don't know why, the middle-aged man suddenly said something that Qiong Nai didn't expect at all, "Haiyuan, after entering the school, how about being my assistant too?" ”

"Ah...... Huh? ”

"Although Kurkov is relatively comprehensive, I am confident that I can still beat him in the special topic of quantum electrodynamics. Besides, we old guys also need you young people to keep your minds alive and creative. ”

"Please don't add to my pressure. And you're nowhere near the age to be called an 'old guy', right? ”

"Haha. It's a little early, but let's think about it, and I'll wait for your response at Tokiwadai then. That's all for today's lesson, so you can have a good rest. ”

"It's really ......"

Turning off the communication cable and taking off the headphones, Dome suddenly lay down on his bed. Sitting in front of the computer for a long time made her feel a little stiff in her limbs.

The season has entered the middle of winter, and now that the night has already begun, even the interior seems a little chilly. Dome reached for the remote control of the air conditioner and raised the indoor temperature slightly.

This season is no longer too careless, not long ago even his brother, who has been actively involved in sports, suffered from a cold. If it were me, I am afraid that the trouble would be even greater.

"Do you want to move around, it's not worth it if you get fat......"

Dome muttered to herself, though she had never really worried about her figure.

Getting up and changing into clothes that would make it easy to exercise, Dome walked into the gym.

"Huh?"

In the gym, there is also a person.

Maybe it's because he didn't pay attention to the sudden drop in temperature some time ago and contracted some wind chill when exercising outdoors.,Dome's brother has reduced outdoor exercise a little bit during this time.。 Today, perhaps due to bad weather, his style of exercise has shifted from court sports such as tennis to combat exercises such as weight-bearing and punching sandbags.

In my memory, Qiongno has some knowledge of mixed martial arts (a man who has achieved nothing often prefers to watch this kind of confrontational sport). To her surprise, her brother also seemed to have received some fairly professional martial arts instruction - she didn't have the impression of having a professional martial arts instructor at home.

The sandbag, which is used as a target for strikes, appears to be the type that blends into the optical fiber, and will indicate the strike position by controlling the light in different areas according to the microcomputer signal. It is said that it is the product of cheap mass production of new optical fiber technology that will be used in several famous schools such as Tokiwadai, and this kind of high-tech mixed with sporting goods has become more and more popular in school cities.

Dome sat on the sidelines and watched his brother train, feeling a little different.

In fact, there was a time before when the brother and sister didn't know why there were some unexplained estrangements. Mitsuki Haihara also seems to have something on his mind, and this is the first time that this has happened between the two. She didn't know if she had done something excessive unintentionally, although it didn't seem to be the case, but Dome still cared a little bit. At that time, Mitsuki Kaihara even fell ill, and he took care of him for a while before he was cured.

This made Dome uneasy for a while, but it ended well, and the relationship between the brother and sister was restored after that period.

"Test nine, two seconds apart."

Why does this electronic indicator sound seem to use virtual idols that have become more popular recently? Is there anything wrong?

Mitsuki Umihara didn't care at all, he was intently watching for the next light signal while adjusting his breathing.

Under the continuous kick strikes under the very smooth inertial action, the scoring system quickly accumulates results. In a short period of time, there was not even a single mistake.

(That's amazing...... ）

The final statistical result of the scoring is 100% effective hitting rate. This achievement made the onlookers can't help but applaud.

Haiyuan, who only realized that she was here when he heard her applause, scratched his face a little embarrassed. Qiong Nai handed over the sports drink in his hand without care.

"Oh, thank you."

"(Staring) ......"

The dome who didn't speak stared at Mitsuki Haihara.

"This ...... Did I do anything? ”

"No, not at all." Dome hurriedly denied it, and she didn't even notice that her cheeks were slightly red. "It's just a little weird. It seems that brother, you haven't participated in martial arts training before, right? There shouldn't be any such coaches at home. ”

"Can you see that?" Mitsuki Umihara was a little surprised, he had always thought that his sister didn't know anything about this. After all, it is usually difficult for girls to enjoy such sports.

Dome nodded honestly.

"It's not a big deal, it's just that I met a friend who is good at these things and received some guidance from him. Actually, it's not recent, I've been in contact for about a year, but it's only a few months since I really started systematic training. It's just that I don't usually do these exercises at home. ”

"Huh? Isn't that amazing? ”

Although she knew that her brother was quite powerful, it was still beyond her imagination to such an extent.

"Ahem...... Let's talk about your own side. How well are you prepared? ”

"It's okay, but it's still a little difficult."

Dome waited for her brother's reply, but she didn't expect any response.

It is more accurate to say that for quite a long time, Mitsuki Haihara was so dumbfounded and silent, and there was no reaction. After a long time, it seemed as if he was whispering something to himself.

("It's not the first time anyway, I've already been like this anyway, and I'm used to it after a long time anyway......")

If you listen closely, it's all similar complaints.

In fact, after the period of time when the relationship between brother and sister was a little estranged, Mitsuki Haihara sometimes showed this strange appearance. Anyway, I don't know what the hell is going on, but it doesn't have any bad effects.

Except for such subtle fluctuations, the brother and sister should always continue this relationship.

At least that's what Qiong Nai believed at this time.