Once We Lived in Nanjing

That night, the three of them used two spectrum analyzers and tinkered around until eleven o'clock, with no useful results, much to Mom's frustration.

The mysterious signal of BG4MSR was elusive. It was clearly audible through the headphones as if a girl was whispering by one's ear, yet the spectrum analyzer placed in the living room was clueless. Wang Ning banged on the table more than once, asserting that it must be Bai Zhen trying to fool them. After all, Bai Zhen had spent over a decade in the army as a communications technician. Isn't he well-versed in encryption?

"Are you three old sticks going to finish soon? What time is it now? Yang Ming has school tomorrow morning!"

Mom issued an eviction order.

"Come back tomorrow if there's anything else!"

To Mom, anyone who dared to impede Bai Yang's studies or future deserved no mercy. She would eliminate anyone blocking the way, and Bai Zhen, Wang Ning, and Zhao Bowen combined weren't exceptions.

Everyone knew how temperamental little Bowen could be. In his youth, he could even make Bai Zhen kneel and wash clothes, so Wang Ning and Zhao Bowen stood up to leave, and Bai Zhen walked them downstairs.

The spectrum analyzer stayed at Bai Zhen's home for now; Wang Ning couldn't have brought it back alone anyway.

"What do you guys think about this?" Bai Zhen asked while walking down, "My son told me that the girl lives twenty years in the future, that her time only has her left, and all the people in the world have died; buffaloes and deer roam the streets freely."

"Just a few days ago, Yangyang came to my office and asked me about this specific scenario, I thought he was writing a sci-fi novel," said Zhao Bowen, "I didn't expect it to be true. It's unbelievable. What kind of disaster could entirely wipe out humanity in just twenty years?"

"If you ask me whether I believe it or not, I definitely don't," Wang Ning shook his head, "This isn't a movie."

"But we couldn't explain why we couldn't catch the signal from BG4MSR, while Yangyang's amateur radio could," Zhao Bowen added.

"There are many possible reasons for not capturing the signal; time travel is the most far-fetched," said Wang Ning. "I keep saying it's a setup by Bai Zhen, he found a shill, hiding somewhere broadcasting spread-spectrum signals, all in cahoots to pull off this act. By expanding the normal signal into a super-wideband, it sounds just like background noise, impossible to distinguish... Bai Zhen, did I hit the nail on the head? How about we take apart the amateur radio tomorrow when we return?"

"Your amateur radio can decode spread-spectrum signals?" Bai Zhen rebuffed, "Am I staging all these tricks to fool you? What good does that do me?"

"Then it's your son fooling us, it's Yangyang's set up."

"If he's capable of that, then us three are as good as living on a dog," Bai Zhen remarked, "He would have to manually DIY, turn the amateur radio into military-grade. Do you think that's possible?"

"Based solely on that signal, I don't believe BG4MSR is living twenty years in the future," Wang Ning stubbornly stated.

"But he verified it," Bai Zhen said.

"Verified using what?" asked Zhao Bowen, "The time capsule? The one you mentioned before?"

"Yes, the time capsule," Bai Zhen replied. "Bury the time capsule, and then let the other party dig it out twenty years later."

"How could you prevent fraud?" asked Wang Ning.

"With a tritium tube."

"The half-life?" Zhao Bowen immediately recognized the key point.

"Yes, using the half-life to verify time," Bai Zhen nodded. "When the other party digs out the time capsule, the tritium tube is nearly extinguished."

Zhao Bowen and Wang Ning fell silent.

The half-life of a radioactive element is immutable, and this is irrefutable evidence.

Both thought simultaneously, Bai Yang is smart. If he used another method to verify it, they certainly could pinpoint a flaw, but the tritium tube evidence is rock solid, unshakable.

Just like those antique dealers who fabricate ancient artifacts, exposed inevitably under carbon-14 dating.

Zhao Bowen and Wang Ning could wield Occam's Razor, slashing through the implausible hypothesis of time travel, but Bai Yang subtly embedded a hard bone amid those seemingly chaotic clues, and this hard bone is the tritium tube. Occam's Razor blunts upon striking the tritium tube, shocking both men with a numbing realization.

The three reached the ground floor, and Zhao Bowen and Wang Ning told Bai Zhen not to see them out.

"I tell you, Old Wang, Old Zhao, if this is true," Bai Zhen asked looking at their backs, "what should we do?"

"I need to withdraw my housing fund and stop paying for pension insurance ASAP," said Wang Ning. "Twenty years from now, I will have just retired, not even having enjoyed a single good day before the world ends."

Zhao Bowen scratched his head, looked around, and muttered, "If this is true, then it's a big problem... a big problem in every sense and on every level."

···

"BG4MSR, BG4MSR, let's leave it here for tonight. Uncle Zhao and Uncle Wang have left, and we've tinkered all night without any results. I have school tomorrow," Bai Yang prepared to end the communication, ready to rest and wash up. "I have to wake up at 6:30 AM, and the first class is the dreadful English class, OVER."

"What did you find out?"

"Only that I'm the only one who can receive your signal; no one else can," Bai Yang answered. "Uncle Wang is in charge of the volunteer team. Tonight, he called other HAMs who were still awake to try listening at 14255, but they also heard nothing, OVER."

"Why is that?"

"I don't know either," Bai Yang shook his head, "They're still looking into it, OVER."

"Um... Will you come back tomorrow night?" asked the girl.

"Of course." Bai Yang said. "But I have evening self-study tomorrow, so it will be a bit later than tonight. You can wait for me at 14255, OVER."

"BG4MXH, what do you mean by 'evening self-study'?"

"Evening self-study means staying at school to do homework after school ends in the afternoon, all the way until 10 p.m. It's an enormous torture on teenagers' mental health, OVER."

"BG4MXH, is that also part of schooling?"

"Yes, BG4MSR, that's also part of schooling, the necessary tough training every child must go through in their growing process in this era," Bai Yang said. "Countless people fall in this process. Just imagine, an innocent naive teenager, having to deal with homework assigned by seven to eight teachers every evening! It's utterly inhumane, it's unbearably painful, it's hell, it's a slaughterhouse! OVER."

"Seven to eight teachers! You actually have seven to eight teachers!"

The girl sounded envious.

"Is that the point? BG4MSR, the point is the hell, the slaughterhouse!"

Slaughterhouse?

The girl felt horrified again.

"Does everyone have to go to school?"

"Everyone must go to school; it's called compulsory education, OVER."

"What do you learn in school?" the girl asked. "Do they also teach archery, shooting, and wilderness survival? My teacher once told me, before the era of the Dark Moon, schools used to teach fighting, grappling, wrestling, and shooting, and even had exams for them. BG4MXH, those monthly tests you mentioned, did they include fighting and shooting?"

Bai Yang thought to himself which school her teacher graduated from.

Are we really in the same world?

"Our exams...cover subjects like Language, Math, English, as well as Physics, Chemistry, Biology," Bai Yang said. "Everyone sits in a classroom and writes the answers, then they are ranked by score. You probably can't understand, thousands of students desperately compete for a score, everyone desperately studies, all for a tiny number on a test paper, a number that's more important than anything, a number that decides your destiny, you can't imagine it, OVER."

"Thousands of students, so many people, that's wonderful!"

The girl sounded envious again.

"Is that the point? The point is the scores, fighting till heads and blood break over scores!"

Fighting till heads and blood break?

The girl continued to feel terrified.

"BG4MSR, in exams, anyone with a normal brain wouldn't want too many competitors, so the fewer, the better, OVER."

"No, the more, the better, OVER."

"Why?" Bai Yang asked.

"Just because, the more, the better," Ban Xia said. "There should be millions, tens of millions; it's only good when the world is full of people, OVER."

Bai Yang scratched his head.

"BG4MSR, I should go sleep," Bai Yang yawned, glancing at the clock. "Not good... It's half past eleven, why do I always forget the time when I talk to you? I really need to go to sleep sister, you don't have school but I do, good night, 73."

"Will you come back tomorrow night?"

"I will, OVER."

"Be sure."

"Definitely!"

Ban Xia put down the headset.

She spread out the old letters on the table again, staring blankly at the handwriting in a trance, it's strange, it's hard to understand... the person she'd just been talking to was clearly a lively young boy, who could laugh, make trouble, and breathe, so full of energy and vitality, but why does he immediately turn into a person long dead the moment the headset comes off?