I caught my objection and ground it between my back molars.
“This example involved momentum, but we could say much the same thing for the position. Imagine an electron inside a box, unseeable from the outside. We add a partition to the box, dividing it into left and right sides. Since electrons are waves, it has not been put in one or the other side; it exists simultaneously in both. When we open the lid to observe it, only then is the electron particle discovered to be on the left or the right. Until that moment it could have been on either.”
I could see why he’d forbid me from saying I find that hard to believe.
“This is the state of quantum superposition. Building on this, let us examine the concept of quantum entanglement. This is the main point you need to follow.”
I feel like I’ve got an itch on the inside of my head.
“As demonstrated in Einstein’s famous equation, E=mc², since energy and matter are equivalent, it is possible for energy to create matter with mass. Take the elementary particle known as the quark; this was likely born from energy via some impetus. The quark created in that moment was not alone; it was generated in a pair with equal but opposite qualities.”
Let’s pretend I followed that.
“Referencing that, and putting aside the how, we generate two electrons from a single quantum. According to the law of conservation of angular momentum, the spin of these two electrons must be in opposite directions.”
Okay, I’ll take your word for it.
“One will always be observed to rotate up, and the other down.”
Apparently.
“Let us call these Electron A and Electron B.”
No argument there.
“Not to repeat myself, but either Electron A or B spins up, and the other spins down. They cannot both have the same spin. If A is up, B is down; if A is down, B must be up.”
That much I can follow.
“Let’s imagine we haven’t observed these two electrons. We keep Electron A with us, then send Electron B to the other side of the world—somewhere in Brazil. Then we observe the electron we kept, Electron A. Fifty percent chance of being up or down; now we know which. Let’s say this observation determines that Electron A’s spin is up. That automatically means that Electron B, in Brazil, has a down spin.”
O…kay. Right.
“As I mentioned beforehand, the direction of the spin was not preordained, but determined entirely by probabilities at the moment of observation. In other words, it was equally likely that Electron A would be observed to have a downward spin. In that case, Electron B would automatically have an upward spin. However…”
However?
“That begs the question—how did the electron in Brazil know that Electron A had been observed? Like I said at the start, a single electron always has a fifty percent chance of spinning up or down. It’s as if Electron B thought, ‘A’s been observed spinning up, so I’d better spin down,’ and determined its own spin accordingly.”
I’d like to voice a doubt but can’t quite put it in words.
“The same thing would be true if Electron B was not in Brazil, but on the far side of the galaxy. No matter how far apart the two elections are, they remain a set, as if they are bound together, and that link cannot be severed. That’s what we call quantum entanglement.”
Nagato had mentioned that on the ship.
“And we have to assume that information transfer between these two electrons occurs faster than the speed of light. If one is observed, then no matter how great the distance between them, the other’s state is determined in that same instant. This contradicts the theory of relativity, and Dr. Einstein’s displeasure at the concept is a famous event in physics history.”
Now that I think about it, it’s not like I really understand the theory of relativity, either.
“Let us call the entangled electrons an EPR pair. Those letters are from the initials of three scientists who raised objections to quantum theory at the time—E being Einstein.”
Was this name chosen out of spite?
“So, have you managed to follow all of this? Superposition and entanglement are vital concepts, so I really need to force this point.”
We can’t do a more basic comparison?
“I suppose…when someone is just tossing ideas around inside their head, that’s one thing, but once two people pit their ideas against each other, then relations get entangled.”
“That metaphor is inapplicable,” Nagato interjected, speaking for the first time.
Koizumi hung his head.
“Well, that’s the best primer I can give. I could get into the uncertainty principle, or time symmetrization, or that famous cat, or quote Feynman, but those aren’t strictly relevant to our current predicament, so I must leave them out.”
So this whole lecture is somehow related to understanding the mess we’re in?
“It is. Right, Nagato?”
“Substantially.”
“So, using what we’ve learned as a baseline, let us consider what we actually are. Applied theory.”
Professor Koizumi’s lecture in the Nagato seminar seemed far from over.
My eyes wandered to the stage below and found a ballroom in the Spartan palace, with Menelaus and his wife, Helen, warmly receiving Paris and the Trojan contingent.
Dude was about to experience the tragedy of NTR, and Helen was supposed to be a world-class beauty, so I scoped them out and was mildly surprised—but convinced.
“Well, then.”
Once, they were the prince and princess kidnapped by a demon lord, another time they were from some galactic empire, kidnapped by pirates, and still another time, they’d been ranchers held hostage by outlaws in the American West—that same man and woman who were constantly getting themselves captured.
Neither was distinctive enough to leave anything more than a vague impression, but this play expected me to believe they were a handsome hunk and the world’s greatest beauty.
Menelaus was just sort of standing there, while the handsome Paris and Helen—who fell for him at first sight thanks to the goddess’s meddling—were staring into each other’s eyes. Dramatic music was trying real hard to sell the hand of fate at work. Keeping one ear tuned to the unseen orchestra, I glanced at the thrones beside me, and found Haruhi and Asahina savoring the endless stream of dishes, elegantly enjoying the play.
Sensing someone else looking, I turned.
“…………”
Nagato was also staring at them. No—just at Haruhi.
I felt like I detected a hint of urgency in her inert expression, but perhaps she caught me looking—she broke off her stare.
Why would Nagato be staring at Haruhi here?
“Now, then,” Koizumi said, like an old-timey detective who’d just assembled all the suspects at the scene of a crime. “We are here—but what are we? What is this world? What are we doing here? Let us turn our minds to these and other questions.”
Sounds like he had all the answers.
Koizumi stole a glance at Nagato and did not seem especially disappointed when she refused to meet it.
“On the pirate ship, Nagato suggested that this is a virtual space, and we’re a quantized portion of our actual selves. I’ve been considering this ever since.”
Come to think of it, when did you first realize this wasn’t real, but VR? Amazed you didn’t find yourself forgetting that.
“Yes, well—that initial fantasy world was far too unreal. I’ve had my doubts all along. I found if I focused my mind on a single topic, that was enough for me to avoid the amnesia effect. Still, it did repeatedly slip from my mind, only to come back after the fact.”
Acting like an MC, he waved dramatically.
“Can we get a word from Nagato here?”
Nagato intoned, “At an unknown point in the real world, we seem to have collided with virtual particles in a quantum state.”
……………Koizumi, interpret.
He plucked an apple from the fruit tray, a silver knife in his free hand.
“I assume a dual-aspect virtual particle collided with the five members of our SOS Brigade. We and this particle interacted, causing a dissociation—and quantizing us.”
He sliced the apple in two.
“Our real-world selves and the versions of us here are both in a state of superposition and EPR paired—is what Nagato is trying to say.”
Nagato’s head shifted. I took that as a nod.
“Okaaay,” I groaned. “And to do something that nuts…”
“If not the Data Overmind, then something else from outer space. Space is vast, after all.”
Still, I didn’t want to picture the galaxy stuffed full of godlike entities we could not even perceive. I needed less headaches in my life.
“So,” I said, “what are these dual aspects?”
Koizumi’s gaze turned up, then all around.
“Remember the situations we’ve found ourselves in. The fantasy RPG, the space patrol, the Western, the gangster film, battling man-eating sharks, piracy on the high seas—and now a page from mythology, the Trojan War.”
Certainly all familiar motifs. Right out of our TV screens or the pages of our comic books.
“There’s your answer,” he said, toying with the apple halves. “They are in a word: fiction. We are inside of a story.”