Once We Lived in Nanjing

Meanwhile.

Bai Zhen and Wang Ning were sitting in the living room, flipping through materials. The paper materials brought back by Zhao Bowen could fill up a suitcase, and the electronic files he brought could fill another suitcase. This afternoon, when Zhao Bowen stacked folders of various colors higher than everyone present, Old Bai and Old Wang thought he had just robbed the print shop downstairs. Then, Zhao Bowen turned around and took solid-state drives out of another suitcase, piling them even higher than everyone—a clear sign he had also raided the electronics market. Patting the folders and hard drives on the coffee table, Zhao Bowen told everyone that this was all the work they had done in the past half-month.

Both found it hard to imagine that Zhao Bowen had completed such a vast amount of work in just half a month, and they marvelled as they went through the documents.

"Nanjing City's high-altitude ionosphere F2 layer... Balloon-suspended radar reflection experiment..."

"September to December, full frequency band broad-area surveillance records of electromagnetic signals in East China."

"September to December, sunspot activity and Earth's magnetic field changes monitoring records."

"Map of the cosmic microwave background radiation... What's this? CERN? European Organization for Nuclear Research?" Bai Zhen frowned, holding a stack of papers in English, and only understood the word "Nuclear", "Nuclear weapons? Goodness, did you also get your hands on nuclear weapons?"

"CERN, the European Organization for Nuclear Research," explained Fan Jiangshu who was sitting across from Bai Zhen, "they study high-energy physics, not nuclear weapons."

"High-energy particle accelerators and Large Hadron Colliders, haven't you seen them in the news?" Wang Ning displayed his extensive knowledge, meanwhile looking down on Old Bai's ignorance.

"Europe? Did you also reach out to Europe?" Bai Zhen asked.

"To be safe, we got a copy of past experimental records from CERN," Fan Jiangshu replied.

Bai Zhen put down the materials in his hand, "Impressive, you have really done a lot in this past half-month."

Upon hearing this, all five of them felt somewhat uneasy, as if they were uncomfortable all over. Almost in unison, they glanced sideways at Bai Yang's room, then Fan Jiangshu spoke in a lower voice, "Isn't it all because of the 'Iron Hand Grim Reaper'?"

"Iron Hand Grim Reaper?"

Bai Zhen and Wang Ning were taken aback.

"Old Zhao?"

Fan Jiangshu nodded: "Teacher Zhao."

"Why call him 'Iron Hand'?" Bai Zhen asked.

"Because he always makes people clap," replied Chedi Mouse with a helpless expression, "you couldn't stand it without iron hands."

"Why call him 'Grim Reaper'?"

"Take a look at how he looks when he rushes you to work," replied Chuanshan Mouse, sitting on the same sofa, still with a lingering sense of fear, "Not even the donkeys in the production team work like that."

Bai Zhen opened another heavy black folder; on the first page was a conspicuous red seal—"Top Secret."

"Snap!" He closed the folder instantly.

"Can we really read this for free?" Bai Zhen looked up and asked.

"Feel free," nodded Chedi Mouse, "You can look at any documents brought here, and you need to know about them."

Bai Zhen took a deep breath and solemnly flipped open the folder. Since the time he took the college entrance examination at the age of twenty, Bai Zhen had never come across documents with such a high level of confidentiality.

He felt like an important person at this moment.

The folder contained a project plan for an engineering project, a thick tome of over a hundred pages.

"China Construction Eighth Engineering Bureau Co., Ltd."

"Chinese Academy of Sciences Zijin Mountain Observatory."

"Rock Physics and Reservoir Geomechanics Laboratory, Institute of Geology and Geophysics, Chinese Academy of Sciences."

"What a long name," Bai Zhen muttered softly, "Nanjing City Deep Earth Rock Mechanics Major Science Project... Rock mechanics? That's civil engineering, right?"

Wang Ning also leaned over curiously to look.

The two of them flipped page by page, casually browsing and got a rough understanding of what the project plan entailed. It was a scientific project to study the impact of human engineering on the deep underground geotechnical structure of Nanjing City, planned jointly by the Chinese Academy of Sciences Zijin Mountain Observatory and the Chinese Academy of Sciences Geology Institute, with the construction under the responsibility of China Construction Eighth Bureau. According to the plan in the project book, they were to dig a deep pit in Nanjing City and install a small unmanned laboratory to measure the stress conditions of the rock layers.

But Bai Zhen didn't understand why he was shown this; he wasn't in the geological and civil engineering field. Why was a scientific project on geology and rock mechanics mixed into the Reverse Future World-saving Amateur Radio Emergency Communication Command Center?

"This is another type of time capsule," Chedi Mouse spoke, "a super time capsule."

Bai Zhen and Wang Ning were surprised.

"In the past half-month, we have been studying methods of Time Slow Delivery. We have already confirmed that a sufficient distance can evade the Great Filter, but sending time capsules into space is limited, costly, and the preparation cycle is long, constrained by rocket capacity. So, we have been actively researching other viable methods," continued Chedi Mouse. "Chief Wang, a previous experiment of yours inspired us. You embedded a time capsule into the wall with concrete."

"To be precise, it was the community gate."

Wang Ning curled his lips; that time capsule was still embedded in the gate of Meihua Villa community.

"This proves that in addition to sending the time capsule into space, giving it enough strong protection and fixation can also ensure its successful survival to the doomsday era," said Fan Jiangshu.

"This is also a means of weakening purposefulness?" Bai Zhen asked.

"Yes, this can weaken purposefulness." Fan Jiangshu nodded, "We bury it deep underground and seal it off; indisputably, in essence, it is no different from being sent to Mars' orbit."

"So what is it that you guys are sending over this time?" Bai Zhen asked.

"It's the black box." The voice of Zhao Bowen suddenly rose.

Everyone turned their heads together to see Zhao Bowen with his arms crossed, leaning against the door frame of Bai Yang's room.

"What we are sending over this time is a black box," Zhao Bowen walked over. "Do you know what a black box is? Every commercial airliner carries a black box, which is a recorder with a sturdy shell, cyclically recording the internal communication logs of the aircraft. In case of an air disaster, the black box provides the most direct and clearest evidence, allowing people to analyze the causes of the disaster. What we are sending to the future is such a black box. It will tell us precisely what happens in the future."

"A recorder?" Wang Ning asked.

"An robot." Zhao Bowen said, "An AI system, which will experience everything in the next twenty years for us, and then tell us exactly what the apocalypse looks like."

"Hard to imagine," Bai Zhen said.

He pictured a little robot like WALL-E in his mind; when disaster strikes, the little machine would find a place to hide, stay hidden for twenty years, until BG4MSR found it.

"It's not as complicated as you think. Our era itself is a world where information technology is highly developed, with immense data flow being transmitted between everyone's mobile phones every single day. No matter what happens, news will break out on the internet immediately. So the black box doesn't need to actively search for information. It only needs to listen, hidden in the deep underground listening to the world's noises—it has a keyword capturing and filtering system. Once it detects suspicious information, it will capture and store it," Zhao Bowen explained, "This technology is actually very mature. The government departments use this method for public opinion monitoring. We just directly copied a set from Tencent."

"Then you have to ensure its safety," Bai Zhen said, "Make sure it can survive the next twenty years, and still function normally after the apocalypse."

"This is the most difficult to achieve. We can't launch it into space, so the safest place is underground," Zhao Bowen nodded, "Dig a deep pit and bury it."

"This thing must be much larger than a time capsule, right?" Bai Zhen asked, "Based on your description, it must require at least a server room, as well as data transmission lines, power systems, and cooling systems…You're planning on digging a deep pit to bury this huge setup. That's a terrifying amount of engineering work."

"We'll make use of what's already there."

"Already there?"

Zhao Bowen pointed to the ground beneath their feet, "Right under our feet, in the underground of this city, there is already a vast and interconnected tunnel system."

Bai Zhen and Wang Ning suddenly realized.

That's right, under this city, there indeed exists an extensive system of tunnels, with thousands of people moving through them underground every day.

The subway.

"We have comprehensively surveyed Nanjing City's subway system. Taking various factors into consideration, we finally selected two locations." Zhao Bowen spread a map on the coffee table, took out a marker, and drew two circles—one at Drum Tower Park, and one by Mochou Lake. "Beneath the office building of the Chinese Academy of Sciences Zijin Mountain Observatory is Line 4, and next to Mochou Lake is Line 3's Mochou Lake station."

Like most underground labs in the world, Zhao Bowen's method is to dig branching tunnels from existing tunnels. Jimping Mountain in Sichuan houses the world's deepest dark matter laboratory, which is a space diverged from a tunnel traversing a mountain, with 2,600 meters of mountain rock overhead. Nanjing's Line 3 has Jiangsu Province's deepest subway station at Mochou Lake Station. Zhao Bowen branched a small tunnel from Line 3's passageway, above which lay a 30-meter thick layer of soil and rock.

"We'll dig a secret chamber beneath the observatory, and another next to Mochou Lake station—as backup for each other. All equipment can be transported through the subway station into the secret chamber, and once everything is set up, we'll seal the entrance from the subway tunnel," Zhao Bowen explained, "This way, from the surface we only need to dig a very small passageway that is just enough for a person to pass through, reducing the volume of construction work by at least eighty percent."

"What about the power system?"

"Nuclear batteries." Zhao Bowen replied without hesitation, "Multiple nuclear batteries linked together to generate electricity can last for more than twenty-five years."

"And cooling?"

"Next to Mochou Lake station is a lake, we've designed a water-cooling channel," Zhao Bowen answered, "The secret chamber underneath the observatory is less deep and can therefore be ventilated."

This guy has already considered everything.

Just how much have they accomplished in mere half a month's time?

"We have four teams advancing simultaneously, Teacher Zhao is the second in charge of the entire project," Fan Jiangshu said.

"I did say I would bring an army of thousands."

Zhao Bowen looked proudly over everyone: Am I amazing or what?

Bai Zhen: Amazing!

Wang Ning: Amazing!

Zhao Bowen: Applause!

The whole room burst into warm applause.

"The official explanation of the entire project to the public is that it is a geomechanical science project, but its true purpose is absolutely confidential. The overt purpose of the excavation is to install rock stress detection devices, when in fact, it is to bury a data recording system," Zhao Bowen continued, "Once this system is sealed, only one person in the whole world will be able to open it."

"BG4MSR," Bai Zhen said.

This is indeed a super time capsule, employing countless resources and manpower to carve out a space underneath Nanjing City, which only that girl can open.

"Among all of us, Teacher Zhao, you treat her the best," Wang Ning said, "One gift after another, reaching for the moon in the sky and diving for turtles in the oceans."

"When does this project start?" Bai Zhen asked.

"Start?" Zhao Bowen let out a cold snort and said dismissively, towering above the rest, "It's already completed."