“I’m truly sorry, we’re back again.”

Zhao Bowen gave a bitter smile.

“Uncle Zhao.”

Bai Yang changed his shoes at the entrance. He couldn’t quite figure out what kind of situation this was—why had Zhao Bowen made this sudden return? Hadn’t he disappeared with the radio, leaving without a trace?

Bao Longtu once again presided over the Kaifeng Prefecture, with Wang, Ma, Zhang, and Zhao arranged on both sides. On the tea table sat a large stapler. Five unfamiliar middle-aged men were either standing or sitting, their expressions solemn. The scene was grander than last time—previously there were three Imperial Cats, this time it was the Five Rats stirring up trouble in the Eastern Capital. Bai Yang swept his gaze across them: the one standing against the wall on the far left was slightly thin with a long face and aquiline nose—Bai Yang dubbed him the Sky-Penetrating Rat. The second from the left sat on the sofa with his arms crossed and eyes closed in meditation—he named him the Earth-Penetrating Rat. Sitting together with the Earth-Penetrating Rat was the River-Crossing Rat, and across from him sat the Mountain-Crossing Rat. The last one, the Brocade-Furred Rat, looked the youngest, probably not yet thirty, standing on the right side of the living room.

Not only had Zhao Bowen returned, but Wang Ning was back too.

Old Wang was currently sitting with his legs crossed, flipping through a thick stack of materials.

After changing his shoes, Bai Yang walked into his room with his backpack, shocked to find that the Icom 725 had already been returned to its original owner, sitting properly on the bookshelf, almost exactly as it had been before.

Zhao Bowen followed him in and sat on the bed.

“What happened?” Bai Yang put down his backpack. “Why is it back? Have you finished your research? Are all the problems solved?”

Zhao Bowen shook his head.

“During this time, we only achieved one result, only figured out one thing. Besides that, we know nothing.”

“What thing?”

Zhao Bowen stood up, leaned against the bookshelf, and gently patted the radio’s casing.

“Yang Yang, have you ever asked BG4MSR where she lives?”

Bai Yang was startled.

“Meihua Mountain Villa.”

“Which building, which number?” Zhao Bowen continued asking.

Bai Yang hesitated, then scratched his head. “I… I never asked. After all, it’s not very polite to directly ask a girl for her specific address… Besides, she’s living alone in an apocalyptic era, so asking which building and unit number doesn’t mean anything…”

“Indeed, it doesn’t mean anything,” Zhao Bowen said. “But because of this, you missed a very important piece of intelligence.”

“Intelligence?”

“Yes.” Zhao Bowen nodded. “Let me ask you another question: do you know which radio BG4MSR uses?”

“How could I possibly know that?” Bai Yang was surprised. “There are so many IC-725 radios in the world, almost every old HAM operator has one.”

“See, you haven’t made the connection, you’re too close to see it.” Zhao Bowen pointed at him. “But that’s normal. We only gradually realized this point after multiple tests. I’ll tell you now where BG4MSR lives and which IC-725 radio she uses.”

“You… you know?”

“Can’t be one hundred percent certain, but I’d say it’s about ninety percent likely.” Zhao Bowen answered, “BG4MSR lives at 66 Mushu Garden Street, Qinhuai District, Nanjing City, Meihua Mountain Villa, Zhongqin Court, Building 11, Unit 2, Room 804.”

“That’s my address!” Bai Yang jolted.

“But it’s also her address,” Zhao Bowen said.

“Uncle Zhao, you… you mean…”

“That’s right, she lives in your house.” Zhao Bowen pointed at the floor beneath them. “Maybe even in the same bedroom, lying in the same bed—you’ve been sharing a bed for two months without realizing it.”

Bai Yang was dumbfounded.

“Holy shit.”

“Now about the radio, you should have guessed already.”

Bai Yang’s gaze fell on the radio.

“Her IC-725…”

“Exactly.” Zhao Bowen patted the radio’s casing. “It’s this very IC-725.”

“Want to know how we discovered this? Well, that’s quite a long story.”

“I’ve got enough data.” Bai Yang sat down. “Tell me slowly.”

“I had suspicions early on. We knew from the beginning that this radio’s energy wasn’t radiating outward, right?” Zhao Bowen sat down as well. “The spectrum analyzer couldn’t detect its electromagnetic radiation. So where did that energy go? Where did the high-frequency vibrations generated by the radio’s crystal oscillator go?”

“We don’t understand the mechanism of trans-temporal communication. There must be a cause behind this that we can’t comprehend. Since we couldn’t detect the electromagnetic waves radiating from the radio at 14.255MHz, it’s unlikely that the radio waves were transmitted and then crossed through time and space. More likely, it was transferred to 2040 while still inside the radio.” Zhao Bowen continued, “At the time, we couldn’t determine at which stage it crossed time and space—it could have been at the crystal oscillator stage, the power amplifier stage, or it might have crossed over while still in the internal feedline.”

“Do you know now?”

“Yes,” Zhao Bowen said.

“Where did the signal cross time and space?”

“Right at the source, in the IC-725’s crystal oscillator.” Zhao Bowen said, “That day when we took the IC-725 back, we immediately sent it to Nanjing University of Science and Technology. We borrowed their electromagnetic anechoic chamber—you’ve seen those chambers online, right? The walls are covered with dense pyramidal absorbers. They often put fighter jets and such in these rooms to test electromagnetic component performance. The chamber’s outer shell is a sealed steel structure, and the inner walls are lined with wave-absorbing materials. This kind of chamber can maximize the shielding and blocking of external electromagnetic interference, ensuring a clean electromagnetic environment. We placed the radio inside and conducted comprehensive testing, precisely measuring the electrical levels of various internal components to determine where the signal was being cut off. Finally, we discovered it never left the crystal oscillator. After figuring this out, we developed a preliminary hypothesis about the radio’s trans-temporal communication mechanism.”

“Resonance?”

“Correct.” Zhao Bowen nodded. “Trans-temporal resonance. When your radio’s internal crystal oscillator vibrates, it directly drives the oscillator in the other radio, thereby instantaneously transmitting information. Looking at it this way, the speed at which information travels between your two radios exceeds the speed of light. But since information can’t travel faster than light, I have reason to suspect that the IC-725 you and she have are the same radio—because it’s the same device, from its perspective it’s just talking to itself, so there’s no information transmission, and therefore it doesn’t violate existing laws of physics.”

“When trans-temporal communication is happening, does the law about information not exceeding light speed still matter?” Bai Yang asked.

“No, it doesn’t.” Zhao Bowen said. “But I need some basis for my theory, right?”

“Alright.”

“If the radio you two are using is the same one, then it makes sense that you live in the same place.” Zhao Bowen said. “However, these are all speculations. The experimental results are what proves my theory—we conducted numerous experiments and got a very troubling result.”

“What result?”

“This radio cannot contact BG4MSR once it leaves your bedroom.” Zhao Bowen answered. “We couldn’t recreate your trans-temporal communication no matter what. We tested it in various locations—within Nanjing, outside Nanjing, underground, in the air, even taking it above 20,000 meters altitude, connecting it to ultra-high gain antennas—nothing worked.”

“You… you’ve been working on all this for the past two weeks?” Bai Yang’s eyes widened.

Zhao Bowen nodded somewhat helplessly.

“Not just that. You don’t know the full situation—it’s complete chaos, the people are in chaos, the matters are in chaos. We assembled an expert team as quickly as possible, bringing in everyone we could get. We conducted extensive investigations within our capabilities. To be honest, there isn’t much to research about the IC-725. We examined it inside and out but couldn’t find anything significant.” Zhao Bowen continued, “Finally, we reached a consensus that investigating the cause of the apocalypse twenty years from now through the IC-725 radio isn’t feasible. It’s not a good entry point, so we quickly returned it here, to this place.”

Bai Yang remained silent for a moment, then looked up and asked: “What next? What do you plan to do next?”

“That depends on your opinion.” Zhao Bowen said. “It’s up to you, Yang Yang. We have several plans, but we unanimously believe you’re still the best candidate because you’re most familiar with BG4MSR. Your emotional connection with her is the most stable, and she listens to you the most. Of course, I must admit this is an extremely high-pressure task that shouldn’t be shouldered by a high school student, so if you’re not willing, we also have…”

“I’m willing.”

Bai Yang interrupted Zhao Bowen almost without thinking.

“You can think it over. You don’t need to give me an answer now. We can give you time to consider…”

“No need to consider.” Bai Yang said. “I’m willing.”

Zhao Bowen was somewhat stunned. He watched the young man before him sitting silently in the chair, head lowered, face turned to the side, one foot bent and resting flat on the chair’s surface, both hands pressing on his ankle.

What was he thinking about right now?

Zhao Bowen wondered.

This was a mountain of responsibility, bearing the fate of all humanity. Old Zhao couldn’t imagine what kind of psychological state this required. He was just worried—worried whether those thin shoulders, slender arms, and young spine could bear such an immense burden.