"It's unlikely to be an object. Mr. Daozi casually gave us the mechanical Azure Ox spaceship to study, which suggests there were no secret objects aboard it. He doesn't seem able to conceal anything important on his person either. So I think it's very likely he learned some important information or stole their technology. Of those two, stealing technology is much less likely. If he had stolen technology, I believe he would have handed it straight over to us. He hasn't mentioned a word of it and is in a hurry to leave, so he must have learned some secrets he wasn't supposed to know."
"That rotten old man. He keeps stirring up trouble and leaving us to clean up his mess."
"Zhonghua, you've had too much to drink. Go get some rest. The secret Mr. Daozi knows must be incredibly important, or that civilization couldn't have crossed thousands of light-years to find him. And Mr. Daozi thinks we aren't yet qualified to know it at our current level. It could be an earth-shattering secret."
"What do we do now?"
"If my judgment is correct, that civilization is thousands of light-years away from us, so its pursuing forces will be very spread out by the time they reach here. After all, this is three-dimensional space, and the search area covers hundreds of millions of cubic light-years. Our fleet is huge, but it's insignificant compared with that space. If their search forces are spread thin because of the distance, they might not find us. Even if they do, there may only be a few or a dozen of their warships. Although they're a level above us, it's unlikely they can wipe us out with just that many."
"What if they call in nearby warships for support?"
"That's why our safest option right now is still to find the four-dimensional bubble the old gentleman mentioned."
"Who knows whether what that rotten old man said can be trusted?"
"I think it can, and I also think Mr. Daozi has more secrets," Academician Xiao Yi said, analyzing the situation. "If Mr. Daozi had intended to harm us, there would have been no need to tell us any of this. Secondly, Mr. Daozi is traveling in the Azure Ox spaceship, which can only reach fifty times light speed. He knows the dimensional bubble exists but isn't hiding in it, so he's clearly confident he can escape pursuit. That's well worth considering. There's also how Mr. Daozi learned that the star system-level civilization was pursuing him. And earlier, when Chief of Staff Wen asked about the Abyss, Mr. Daozi's expression made it clear he knew something, yet he flatly denied it. Then there's why that small star sector civilization abducted Mr. Daozi in the first place and what exactly they were looking for. Given the strength of a small star sector civilization, I'm certain it couldn't have been merely to study a member of a species that was still in the agricultural civilization era at the time. What happened afterward raises even more questions. As a leader, he rescued a low-level member of an unfamiliar civilization who was being studied, and they even seemed to have an unusual relationship. All these questions are worth examining."
"Yes, I think there are a lot of questions too. But I believe Mr. Daozi can stand with us. Perhaps we're still too weak, which is why he hasn't told us these secrets. Now he's also told us there's a four-dimensional space bubble nearby. On the surface, he's telling us to hide in it, but everyone knows the value of such things. Perhaps the old gentleman wants us to grow stronger. I keep feeling there are many secrets in the Milky Way that we don't know about, and they aren't as simple as an invasion by the Insect Race." Academician Zeng Zhaoyuan agreed.
"We secretly tested Mr. Daozi's DNA and confirmed that he is unquestionably human. His genes are also closer to those of our ancestors. There's no problem with his identity," Academician Xiao added.
"It's just that none of us has ever seen what a higher-dimensional space bubble actually looks like. The Destroyers mentioned before that the higher-dimensional space bubbles used to deliver insect swarms were at least as big as Earth. Mr. Daozi also mentioned that the bubbles used to deliver insect swarms were several Earths in size. That shows higher-dimensional space bubbles are fairly large, but finding something the size of Earth within a hundred light-years, especially something that isn't even a physical object, will be difficult," Hu Yu said.
Finding an Earth-sized object in a three-dimensional space a hundred light-years across was as difficult as finding a strand of hair in a space the size of Earth. On that scale, even stars became faint points of light, let alone a so-called higher-dimensional space bubble.
"General, since Mr. Daozi said that, he must be confident we can find it. He knows our Deep Blue can only travel at five times light speed, so the bubble is very likely not too far from us. As for how to find it, we still need to study the problem," Academician Zeng said.
"How about this, Old Hu? I'll first send three hundred thousand Hunter-Killers out in all directions, deploying satellites along the way to conduct a wide-area search. We'll leave three hundred thousand to guard the Deep Blue Fleet. The fleet had better stop maneuvering and stay where it is. That way, we'll have the smallest chance of being discovered."
"All right, but the search fleet must wait until the four-dimensional communications network is complete before setting out. The area is too large. Without communications, it would take even longer to pass on the news if they found it. Four-dimensional network communications technology is already basically mature. Academician Zeng, sorry to trouble you with it. Also, try to see if there are other ways to find the space bubble. If we can't find it, we'll have no choice but to face the wrath of this star system-level civilization and fight to the death."
"The four-dimensional network can be completed within a month. I also suggest focusing the search on the space within fifty light-years. If it's too far away, even if we find it, it would take the Deep Blue a long time to reach it, so there would be little point. Mr. Daozi wouldn't do that."
Engineering ships were urgently manufacturing the information relay equipment, while the technicians building the dimensional channels were already hard at work aboard the Hunter-Killers. Six hundred thousand pairs of entangled quanta were extracted. Each warship was a node, and each node had four quanta, connecting it to four other warships.
Aboard the warships, the quanta were held in place by directed magnetic field lines and continuously supplied with energy from several fusion reactors on each Hunter-Killer. Energy was injected into a particle, and when it reached an extremely high level, a particle-based spatial channel slightly wider than a strand of hair appeared. Through the fourth dimension, this spatial channel connected precisely to another quantum aboard another warship. With that, a four-dimensional communications channel was established.
A month later, with three hundred thousand nodes, six hundred thousand channels, 1.2 million channel entrances, and the node relay equipment, a four-dimensional communications network was complete. The channels were no longer as fragile as quanta and would not break even when the warships maneuvered at high warp speeds.
A test message was sent from one Hunter-Killer and relayed through two hundred thousand nodes. Two seconds later, it arrived precisely at another Hunter-Killer. Although there was still a two-second delay, the network surpassed previous quantum and conventional electromagnetic communications in both stability and timeliness. Moreover, its timeliness would not change at all as the warships moved, because their movement took place in three-dimensional space and had no effect on the communications channels in the fourth dimension. That would change only if technology advanced enough for warships to move in the fourth dimension.
With this network, a command ship could issue orders to every warship on the battlefield. Of course, the command ship needed a few more connections to guard against the four ships connected to it all being destroyed at once. When faced with a vast number of warships, the old quantum communications system had allowed only a pyramid-style chain of command. Information could not be passed directly to every warship, and sharing battlefield information was also extremely troublesome. As a result, fleets had often been forced to fight separately, with poor efficiency.
Now, with this four-dimensional communications network, commanders could not only direct every warship in real time and check the battlefield situation at any moment to adjust and deploy tactics, but warships could also communicate instantly with one another. Tactics involving coordination, support, and cover during battle could be carried out more effectively. The entire fleet's combat strength had increased by more than fifty percent.
The three hundred thousand Hunter-Killers had already set out, carrying large amounts of satellite equipment to explore the surrounding space within a hundred light-years. Each Hunter-Killer was nearly three hundred meters long. Gathered together, three hundred thousand of them made an immense sight, like dark clouds blotting out the sun and a rainbow stretching across the sky. But once they entered the vast universe, their number was as insignificant as a handful of salt scattered into the sea. Finding even one of them was incredibly difficult.
Everyone hoped that the three hundred thousand Hunter-Killers and the satellite equipment they scattered along the way would find the so-called four-dimensional space bubble. With each passing day, the chance of being discovered by that star system-level civilization grew. Since that civilization could track the Azure Ox spaceship, which was only a few dozen meters long, there was a very high chance it would also discover this enormous fleet. Although the fleet had stopped maneuvering and hidden itself in the void, no one could guarantee it would escape the star system-level civilization's notice.
If the fleet were discovered by the star system-level civilization, the humans who looked just like Daozi would certainly not meet a good end, especially if they were found in the same region of space. The other side would surely believe that the secret Mr. Daozi knew had been leaked to the fleet. The best outcome would be for the fleet to be escorted back to the star system-level civilization's territory for investigation, but that was unlikely. The simple and efficient solution was to destroy the fleet outright, ensuring the secret would never leak.
What exactly was this secret? If they knew it, perhaps they could negotiate with the star system-level civilization. Even if they couldn't find the four-dimensional space bubble, they might still win a slim chance of survival. At least it would be better than fighting outright. Hu Yu thought about it for a long time but couldn't think what the secret might be. Any secret within a civilization would be insignificant in the wider universe, unless it was the most advanced technology. But how much cutting-edge technology could a star system-level civilization possess? Of course, nothing was absolute. Perhaps some star system-level civilization had suddenly acquired technology that even a great star region civilization had never mastered. But if it was technology, and technology of the highest order at that, Hu Yu believed Mr. Daozi would have given it to the fleet to develop and use directly against that star system-level civilization.
If it wasn't a technological secret, then it had to concern dealings between civilizations, and something that couldn't bear the light of day at that, to make that star system-level civilization cross thousands of light-years to pursue an old man, even at the risk of trespassing into other civilizations' territory. Hu Yu believed the secret must involve more than just one or two civilizations. Two years had passed, and the farthest Hunter-Killer had reached sixty light-years away. After the first group of Hunter-Killers set out, Hu Yu had sent another two hundred thousand to focus on the area within twenty light-years of the fleet. Neither the five hundred thousand Hunter-Killers nor the hundreds of millions of satellite devices had found the so-called bubble.
Several times, the fleet and satellites reported unusual occurrences, but Academician Zeng Zhaoyuan verified that none of them were four-dimensional space bubbles. Right now, the busiest people were neither the fleet nor Hu Yu, but the group of space physicists aboard the science ship. They tried every possible way to locate the bubble, but the fleet's space science was still in its infancy, and the scientists' accumulated knowledge was limited. The repeated failures to verify their findings were a considerable blow to them.
But at least those setbacks proved that certain approaches led nowhere. Under the pressure of the fleet's shared fate, the scientists were shaken by their failures but not discouraged. Instead, they grew more excited. They even forgot the imminent danger, devoting their entire minds and bodies to space research. Any small advance could provide an opportunity to find the four-dimensional space bubble.
Another two years passed in the blink of an eye. The second group of two hundred thousand Hunter-Killers had long since completed their search and returned, while the first group of three hundred thousand were still searching the area within a hundred light-years. That day, a message arrived from the most distant satellite. It was not news of the four-dimensional space bubble, however, but of the arrival of warships from another alien civilization. These warships could travel at more than five hundred times light speed and had enormous hulls several kilometers long, though there were only five of them.
Clearly, this was the fleet of the star system-level civilization pursuing Mr. Daozi. Against a fleet from a civilization of that level, the Hunter-Killers and conventional weapons were no longer of much use. Hu Yu had no choice but to deploy all their antimatter throughout the space around the fleet, hoping that if the other side attacked, these antimatter bombs hidden in space would have some effect.
All three hundred thousand Hunter-Killers guarding the Deep Blue were in position, awaiting the coming battle. The three hundred thousand Hunter-Killers that had been sent out to search first were also ready to return at full speed, but even at their fastest, they would take two or three years to arrive. The enemy ships, traveling at five hundred times light speed, would need only a little over two and a half months to reach the vicinity of the Deep Blue Fleet.
Hu Yu rejected the first group's request to return and ordered the three hundred thousand warships to scatter in all directions, returning only once the crisis had passed. If the Deep Blue Fleet was destroyed and these three hundred thousand warships managed to escape pursuit, they could return to the Tau Ceti System once it was safe. The secret base left on the third planet could help them gradually develop there.
"General!"
"There's no need to say more. This was planned from the very beginning. Your mission wasn't just to search for the four-dimensional bubble. You're also the seed of our fleet. That's why I never ordered you to return. Unless the danger passes, you won't receive an order to come back. I'll use fifty thousand Hunter-Killers to accommodate your families and the hundred-odd thousand scientists and technicians, then send them fleeing in different directions. If disaster does befall the fleet, I hope you'll preserve the spark of our civilization," Hu Yu said solemnly.
Hu Yu knew how cruel this was. The power to decide who lived and who died was now in his hands. No matter whom he chose to live or die, it would be wrong. But for the sake of civilization, he had to do it.
Aboard the science ship.
"Both of you, Academicians, evacuate immediately. The science ship is too slow, and it's a big target. You're the hope of our civilization. I beg you to lead the scientists away at once."
"No, we still have one last hope. I was just about to come find you. I need the entire fleet's cooperation to conduct an experiment," Academician Zeng said. "If the experiment succeeds, we'll have a chance of getting through this danger safely. But if it fails, we might not even have time to escape."