"We may still not be able to truly understand quantum theory in a philosophical sense, but its progress is still immeasurable. www.biquge.info Although we sometimes sometimes miss the classic era, the days when cause and effect were meticulous and the nature of the universe was simple and easy to understand, this is more of a nostalgic emotion. As the beginning of the movie "Gone with the Wind" is not without affection: "There was once a land that belonged to the cotton plantations called the Old South, and in this beautiful world, the gentlemen saluted gracefully for the last time, the knights walked with their beautiful female companions for the last time, and the people saw their masters and their slaves for the last time." And now this is an old dream that can only be found in books, a civilization that has drifted away with the wind. Despite this sadness, people still sing the praises of the final victory of the Yankees in the North, because we have gained more strength, more enthusiasm, and more faith in the future. Still wearing his hat, still carrying his purse, still holding his book, Auston just looked defenseless as he walked through Gensokyo land. Suddenly, he stopped and said in a small voice, "Relatively speaking, among popular science books, this book is my favorite one. Although the physical knowledge described in it is still at a relatively shallow level, it is quite qualified if it is only from the perspective of scientific popularization. But I don't agree with this paragraph...... Sooner or later, humanity will know that all they can gain by going down this path is despair. What awaits physics at the end is the end of the world created by its own hands, because the only thing that is certain in this universe is uncertainty. ”

After saying that, the old man closed the book, put it back in his purse, turned his body in a direction behind him, and pressed his hat with a slight bow: "I really hope you can understand what I just said, but it seems ......"

On the extension of his gaze, a young girl dressed in green with two katanas stumbled out from behind a tree: "...... Uh, what did you just say? I didn't hear ......."

"Let the other one come out too, Miss Soul Dream. Smiling, Alston looked up, "Miss Yuyuko of Saigyoji Temple...... I'm curious why you don't follow an inconspicuous old man like me instead of your own home......"

"Ahh With a fan in her hand, Yuyuko walked out from behind the tree with a smile on her face, "It's just that it's too boring to stay at home...... It's just a matter of coming out and relaxing...... Grab some snacks along the way......"

"Eat...... Some...... ......" Youmeng, who was standing next to her, shook her body, "Eat...... Some...... It's okay, I'm mentally prepared...... It really doesn't matter...... Whining...... It seems that Yuyuko-sama eats a lot more than I expected......"

"Does it really make sense for a ghost to eat? if it's just to replenish the mass, air should be enough, right?"

"How can you say that? Of course it makes sense, it makes sense. Covering her face with a fan, Yuyuko said, "It feels very different to supplement it with different things......

"Ah...... I see. I'm really sorry, but I don't know enough about ghosts. With a look of abrupt realization on his face, Auston nodded, "But if it's just a walk, the two of you can walk on the road openly, why do you have to hide?

"Hmm...... Well, yes, yes, that's what Gensokyo rules are. Obviously having a thought process, Yuyuko nodded her head vigorously, "It's naturally impossible for outsiders to understand...... However, there are a lot of guests today. ”

"What a lot of guests...... Indeed, because the curtain is about to be drawn, it is normal for all the actors to get together. "Hey...... It turns out that those people are all actors arranged by you...... So who's the audience? Is that you?"

"How could it be. Alston smiled and shook his head, "I'm just an actor trying to see the end." There is only one audience, and there will only be one. Want to be a spectator...... We're not even close. ”

"Ahra, it's a play for one audience...... So, who is that audience?" inadvertently, a trace of coldness crossed Yuyuko's eyes, "That's it...... The so-called observer?"

"It's better to stop in moderation, Miss Yuyuko of Saigyoji Temple. All we wanted to do was witness the end, and we didn't interfere too much in the process. Easily blocking the opponent's invisible attack, Auston looked at Yuyuko, who suddenly had a bad face a few meters away, "The observer is not an actor, and it is impossible to be an actor." Observation was his only job, so he couldn't have participated in the show, and the universe had only given him a partial right to cheer. I can imagine the truth that you and Miss Yakumo have deduced, but a large part of it is wrong. However, I can't blame you, you still know too little information, and it's no wonder that you have equated the 'observer' mentioned before the fall asleep with the 'god' mentioned by the Nazi Party in the video. I don't know how to explain this, except to say that the truth is far more complex than you think, and the implications are enormous...... There is a price to pay to learn about it. ”

"What is the cost? What impact can an old story that has been gone for quite some time have passed?"

"Miss Yuyuko of Xixing Temple, it seems that although you are the eldest lady of the Baiyulou Xixing Temple family, you are not at all clear about the concept that the current high-level people in the underworld have. Of course, this underworld refers to the underworld in a broad sense, which includes hell and the other side...... And so on and so forth, all in all, it's a whole system for dealing with special life forms like ghosts. As he spoke, Auston turned away, as if to move on, "Even you, you can't survive the siege of thousands of ghosts......, right?" This development is really strange. So it's a shame that if I'm here to meet Miss Yakumo, maybe I'll be able to tell her what I know. However, as a relationship in the underworld, it is better for you to know as little as possible about this kind of thing. ”

"You ......" let her face return to normal, Yuyuko looked at Auston's back, "Who is it?"

"You can call me Auston Ylan. Just a passerby. Well, goodbye, Miss Yuyuko of Saigyoji. ”

"Wait...... Yuyuko-sama?" Seeing the hand in front of his body, Youmeng, who had wanted to step forward to stop him, let out a puzzled voice, "Why do you want to stop me? We've already put in an intruder, and another ...... in"

"You can't beat him. The other hand stroked his chest, and Yuyuko's face showed a serious look that Youmeng had never seen before, "You definitely can't beat him, just going over and stopping him like this is simply fatal...... Since he said that he would only play the role of a bystander in this incident, then don't provoke him again......"

"But if he's lying......"

"Even if he is lying, we have nothing to stop him. Not at all. Speaking of this, Yuyuko sighed, "Is it really a little too arrogant...... The world is very big......"

"Yuyuko-sama......" His eyes couldn't help but be attracted by Yuyuko's sad and beautiful face, and Yume's hand holding the knife gradually relaxed, "That person, can it really be so strong? so strong that even Yuyuko-sama ......"

"No, youmeng, if you want to stop him, I can still stop him. Anyway, I'm also the eldest lady of the Saiyuji family. Putting down a raised arm, the smile returned to Yuyuko's face, "So Youmeng, let's go eat!"

"Haven't you just eaten up all the stock of that steamed bun shop in the world?

The ...... of the Underworld Looks like there's something I don't know. What's next?

While listening to the shouts of Youmu who caught up behind her, Yuyuko thought as she could.

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"As I should have already mentioned, in classical physics we can use phase space to describe the state of a system. Similarly, in quantum theory, we can use a similar approach, all that needs to be done is to transform the classical phase space into a complex Hilbert vector space. If you can't understand the details with the mathematical tools you currently have, you just need to remember one thing: the state of a complex system can be seen as a point or a vector in some kind of high-dimensional space. For example, let's talk about you, your current state can correspond to a state vector in a certain Hilbert space, in which Sanae Dongfuya is not the appearance of the dignified and beautiful girl now, but a function described by a string of letters and mathematical symbols in the coordinate representation...... You can understand it until here, right?"

"Uh, well, it's mostly understandable...... And then, then, when is it going to be the theory of the multiverse?"

"It's early, don't worry. Sighing at Sanae's strong desire to learn for some reason, Ge Yiwei thought for a while, "Really, what should I say next...... Popular science is really a technical job......"

"Mr. Ge?" Seeing Ge Yiwei's somewhat worried expression, Sanae seemed a little uneasy, "Am I ...... It's so annoying?"

"Annoying? Not really. It's just that my language level is too scummy, I don't know how to say it......" Taking a sip of the tea on the table to moisten his throat, Ge Yiwei knocked his head, "Alas, I'm really sorry, Miss Dongfangu, it's rare that you're so interested, but I don't know what to say......"

"No need Mr. Ge, you don't have to blame yourself!" Hearing this, Sanae hurriedly waved her hand, "I just asked when I was suddenly interested, and I didn't plan to really understand it......"

"In other words, my enthusiasm for studying physics was just extinguished? It's too bad......"

"That's not Mr. Ge! You really don't need to blame yourself, I ...... I ......"

"Don't worry, when will you not even be able to make jokes?" Drinking all the tea in the cup in one go, Ge Yiwei stretched, "Hawkers, this should be the last time to be able to relax for a while...... Tomorrow is going to be busy. ”

"Tomorrow...... Are you really in such a hurry? Wouldn't it be better if we took it a little longer? We have just overcome so many difficulties and returned to Gensokyo, and we are about to go to war again...... It's going to be tiring. ”

"If you don't want to go, you can not go, I have already said that the selection of this mission is voluntary, and I will not force anyone. Slumped in his chair, Ge Yiwei's tone sounded a little lazy, "Even, I'm ready for the most extreme scenario: no one wants to participate except me and Miss Kumingdi...... Well, it's a bit bottomless. ”

"But it's a pity, my brother is dead. Before Sanae could speak, Ge Yiwei suddenly sighed, "He's also an agent no matter what, if you can win him over, maybe it will help somewhat......"

"Mr. Ge, you ...... Do you still have some resentment against Alice?"

"Resentment? What's the use of that? Can I pick up my gun and blow her head right now? Even if I could, what good would I gain by killing her now?" Ge Yiwei said calmly, "But he just died this morning, and it would be absolutely a lie to say that there was no emotional turmoil at all." But after all, people are dead, and when they die, there is nothing...... I seem to have said that before...... Ah, by the way, I mentioned it in the conversation with my boss. ”

"When a person dies, there is nothing......" Sanae repeated the other party's words softly, remembering the appearance of Reimu in the hospital when she put Ge Yiwei's pistol on her chest. Seeing this scene, Ge Yiwei smiled: "Miss Dongfeng Valley, why does this kind of vulgar sentence make me feel like a famous quote from a great man?"

"Indeed, it is indeed a common saying, people die...... There was nothing left. So, while you're alive......" Sanae suddenly raised her head, "Mr. Ge, can you make a statement now? I hope to participate in this mission." ”

"Participating in this mission, don't regret it?" Looking at Sanae's serious expression, Ge Yiwei nodded, "Ah, of course I'm happy to have a helper...... But Miss Dongfenggu, if you want to regret it, you can do it, and the final decision will be made tomorrow at four o'clock in the morning after I change the medicine. I think it's better for you to discuss this matter with Miss Yasaka. Anyway, you're also a shrine maiden at Moriya Shrine, so they're your boss......es, right?

"Mr. Ge is not the same. Did you ever get permission from Reimu to do so? I don't think I had a single one, did you?"

"It's different, it's not different. Ge Yiwei waved his hand, "I'm just...... It's just, well, how can I say it......"

"Don't think of excuses, Mr. Ge, that's the way it is. Although you call Reimu your boss verbally, you haven't heard her speak of it once. What is this called, ah, unorganized and undisciplined, not following the orders of superiors, right?"

"You ......" Looking at the mischievous smile on Sanae's face, Ge Yiwei helped his forehead, "You're taking revenge for my joke just now......, right? Isn't it funny to just look like I can't speak?"

"Of course it's interesting, it's really interesting. Sanae nodded, "But Mr. Ge, are you really in such a hurry, can you start tomorrow just after changing the medicine?"

"The youkai in the Earth Spirit Temple don't have that time. They are still struggling to hold on even though they are surrounded by a large army, and if they drag on any longer, they will add more variables. And, I also want to know what I want to know earlier. Ge Yiwei stood up, "So, Miss Dongfeng Valley, although it may be a little late, but-"

"I hope you can accept my apology?"

"Hey, Mr. Ge?" Looking at Ge Yiwei who bowed in front of him, Sanae quickly stood up, "Don't do this! Your wound is not healed yet, is it really okay to do this kind of action?"

"Ahh Still, I hope you accept my apology. For the matter of throwing you in Mongolia without permission......"

"That's not Mr. Ge's fault! because a lot of things have happened...... All in all, it's not Mr. Ge's problem!"

“…… When you say that, I am a little cautious. Well, let this matter pass. Straightening up, Ge Yiwei smiled, "I still have some things, so I'll go out first." If you can...... See you tomorrow morning, Sanae in the East Wind Valley...... Homosexuals. ”

“…… Well, I'll see you tomorrow morning, Mr. Ge. ”