Death's End

by Cixin Liu

  And then they slept. Dreamless.

  PART V

  Bunker Era, Year 67

  Orion Arm of the Milky Way

  Examining the data was Singer’s job; judging the sincerity of the coordinates was Singer’s joy.

  Singer understood that what he did wasn’t important—it just filled in the pieces. But it had to be done, and the task was enjoyable.

  Speaking of enjoyment, when this seed had departed from the home world, that world was still a place full of joy. But later, as the home world began to war against the fringe world, joy diminished. By now, more than ten thousand grains of time had passed. There wasn’t much joy to speak of on the home world or in this seed. The happiness of the past was recorded in classical songs, and singing those songs was another of the few joys left.

  Singer sang one of these classical songs as he reviewed the data.

  I see my love;

  I fly next to her;

  I present her with my gift,

  A small piece of solidified time.

  Lovely markings are carved into time

  As soft to the touch as the mud in shallow sea.

  Singer did not complain much. Survival required so much thought and mental energy.

  Entropy increased in the universe, and order decreased. The process was like the boundless wings of the giant balance bird pressing down upon all of existence. But low-entropy entities were different. The low-entropy entities decreased their entropy and increased their order, like columns of phosphorescence rising over the inky-dark sea. This was meaning, the highest meaning, higher than enjoyment. To maintain this meaning, low-entropy entities had to continue to exist.

  As for any meaning higher than that, it was pointless to think about. Thinking about the subject led nowhere and was dangerous. It was even more pointless to think about the apex of the tower of meaning—maybe there wasn’t an apex at all.

  Back to the coordinates. Many sets of coordinates flitted across space, like the matrix insects flitting across the sky of the home world. Picking up coordinates was the job of the main core, which swallowed all the messages passing through space: medium membrane, long membrane, light membrane, and maybe one day even short membrane. The main core remembered the positions of all the stars. By matching the received data against various map projections and position schema, it could pick out the coordinates of the messages’ origin. It was said that the main core could match position schema from five hundred million time grains ago. Singer never tried anything like that—it would be meaningless. In that distant age, the low-entropy clusters in space were rare and far apart, and had not evolved the hiding gene and the cleansing gene. But now—

  Hide yourself well; cleanse well.

  Out of all the coordinates, only some were sincere. Believing in insincere coordinates meant cleansing empty worlds. This was wasteful. And there were other harms besides. These empty worlds might be useful in the future. It was incomprehensible why anyone would send out insincere coordinates—they would get what they deserved someday.

  Sincere coordinates followed certain patterns. For instance, a mass cluster of coordinates was usually insincere. But these patterns were all only heuristics. Judging the sincerity of coordinates effectively required intuition. The main core on this seed was incapable of this task, and even the supercore back on the home world could not do it. This was one reason why low-entropy entities had no substitute.

  Singer had this skill, this intuition, but it wasn’t a gift or instinct; rather, it was something honed by the accumulated experience of tens of thousands of time grains. A set of coordinates seemed nothing more than a simple matrix in the eyes of the uninitiated, but to Singer, it was alive. Its every detail was expressive. For instance, how many reference points were taken? What was the method for marking the target star? And many other subtle details besides. The main core was able to provide some information, such as the historical records associated with this set of coordinates, the direction of the coordinate broadcast source, the broadcast time, and so forth. Together, these formed an organic whole, and what emerged in Singer’s consciousness was a sense of the coordinate broadcaster himself. Singer’s spirit crossed the chasm of space and time, resonated with the spirit of the broadcaster, and felt its terror and anxiety, along with other feelings unfamiliar to the home world, such as hatred, envy, greed, and so on. But for the most part, it was terror. Terror was what endowed a set of coordinates with sincerity. For all low-entropy entities, terror guaranteed existence.

  Just then, Singer noticed a sincere set of coordinates near the course of the seed. The set of coordinates was broadcast by long membrane, and even Singer himself couldn’t be sure what told him that the set of coordinates was sincere—intuition could not always be explained. He decided to cleanse it. He wasn’t busy, and the task wasn’t going to distract him from singing. Even if he got it wrong, it was not a big deal. Cleansing was not a precision task and didn’t require absolute accuracy. It also wasn’t urgent. He just had to get it done eventually. This was also why his position wasn’t prestigious.

  Singer took a mass dot out of the seed’s magazine, then he turned to look for the star indicated by the set of coordinates. The main core guided his gaze, like a spear sweeping through the starry sky. Singer grasped the mass dot with a force field feeler and prepared to flick it. But then he saw the location indicated by the set of coordinates and the feeler relaxed.

  Of the three stars, one was missing. There was a white cloud of dust in its place, like the feces of an abyss whale.

  It’s already been cleansed. Nothing more to do.

  Singer put the mass dot back into storage.

  That was fast.

  He activated a main core process to trace the source of the mass dot that had killed that star. This was a hopeless task with almost zero chance of success, but required by established procedure. The process soon terminated, and like every other time, yielded no results.

  Singer soon understood why the cleansing had happened so fast. He saw a slow fog in the vicinity of that destroyed world. The slow fog was about half a structure length away from that world. Seen by itself, it wasn’t apparent where the fog had come from, but when connected with the broadcast coordinates, it was obvious that the fog belonged to that world. The slow fog showed that the world was dangerous, which was why the cleansing had come so quickly. It appeared that there were other low-entropy entities with even sharper intuition than he; but that wasn’t strange. It was as the Elder said: In the cosmos, no matter how fast you are, someone will be faster; no matter how slow you are, someone will be slower.

  Every set of broadcast coordinates would eventually be cleansed; it was just a matter of sooner versus later. One low-entropy entity might think this set of coordinates insincere, but on the millions upon millions of low-entropy worlds there were billions upon billions tasked with cleansing—someone would think it sincere. All low-entropy entities possessed the cleansing gene, and cleansing was an instinct. Also, cleansing was a very simple thing. The cosmos was full of sources of potential power—one just had to trigger them to complete the task. It required so very little, and didn’t even delay singing.

  If Singer were patient, all sincere coordinates would eventually be cleansed by other, unknown low-entropy entities. But this was not a good thing for either the home world or the seed. Since Singer had received the set of coordinates and even glanced at the world pointed to by the coordinates, Singer had a connection to that world. It would be naïve to think of this connection as unidirectional. Recall the great law of reversible discovery: If you could see a low-entropy world, then that low-entropy world could also see you—it was only a matter of time. Thus, waiting for others to complete cleansing was dangerous.

  The next task was to put this now-useless set of coordinates into the data bank called the tomb. This was also required by established procedure. Of course, all other information having to do with the location needed to go into the data bank as well, just as pers
onal effects were buried with the body, as was the custom on the home world.

  Among the “personal effects” was something that piqued Singer’s interest. It was a record of the dead world’s three communications with another location using medium membrane. Medium membrane was the least efficient communication membrane, also called primitive membrane. Most communications preferred long membrane, though it was said that even short membrane could be used to convey messages. If true, that would make the communicators akin to gods. But Singer liked primitive membrane. He thought primitive membrane possessed a simple beauty, symbolizing an age full of joy. He often turned primitive membrane messages into songs. He thought they sounded pretty, even if he didn’t understand them. Understanding them wasn’t necessary, however; other than coordinates, primitive membrane messages didn’t have much useful information. It was enough to enjoy the music.

  But this time, Singer was able to understand some of the message, because some parts carried a self-decoding system! Although Singer was only able to understand a little, grasp an outline, it was enough for him to see an incredible history.

  First, the other location had broadcast a message via primitive membrane. The low-entropy entities of that world clumsily plucked their star—Singer decided to call them the Star-Pluckers—like ancient bards of the home world plucking the strings of the rough country zither, to send out the message. It was this message that contained the self-decoding system.

  Although the self-decoding system was primitive and clumsy, it was sufficient to allow Singer to see that a subsequent message sent out by the dead three-star world followed the same encoding scheme—apparently an answer to the first message sent by the Star-Pluckers! This was already nearly inconceivable, but after that, the Star-Pluckers responded again!

  Interesting. Very interesting!

  Singer had indeed heard of low-entropy worlds that possessed neither the hiding gene nor the hiding instinct, but this was the first time he had seen one. Of course, the three communications between these two would not reveal their absolute coordinates, but they did expose the distance between the two worlds. If the distance were fairly large, it wouldn’t be a big deal either; but the distance was very short, only 416 structures—the two worlds were practically on top of each other. This meant that if one world’s coordinates were exposed, the other would also be exposed—it was just a matter of time.

  This was how the Star-Pluckers’ coordinates were revealed.

  Nine time grains after the first three communications, another record appeared: The Star-Pluckers plucked their star again to send out another broadcast … a set of coordinates! The main core was certain that it was a set of coordinates. Singer looked for the star indicated by the coordinates and saw that it had also been cleansed, about thirty-five time grains ago.

  Singer thought that perhaps he had been wrong. The Star-Pluckers must have possessed the hiding gene. They obviously had the cleansing gene, so it was impossible that they didn’t also possess the hiding gene. But like most coordinate broadcasters, they didn’t have the ability to cleanse on their own.

  Interesting. Very interesting.

  Why did whoever cleansed the dead three-star world not also cleanse the world of the Star-Pluckers? Many possibilities. Perhaps they hadn’t noticed these three communications—primitive membrane messages often didn’t get much attention. But given the millions upon millions of worlds out there, someone would have noticed—Singer was just one who did. Even without Singer, some other low-entropy entity would have noticed them; it was just a matter of time. Or perhaps they had noticed them, but decided that a low-entropy group that didn’t possess the hiding gene wasn’t much of a threat, and cleansing them was more trouble than it was worth.

  But that would be a mistake, a terrible mistake! Broadly speaking, if low-entropy entities like these Star-Pluckers really didn’t have the hiding gene, then they would not be afraid of exposing their own presence, and they would expand and attack without fear.

  At least until they got killed.

  However, as applied to this particular case, the situation was more complicated. The first three communications were followed nine time grains later by the coordinate broadcast. Then, sixty time grains after that, there was another long-membrane coordinate broadcast from somewhere else, pointing at the dead three-star world. The chain of events painted an uneasy picture, a picture that indicated danger. The cleansing against the dead three-star world had happened twelve time grains ago, so the Star-Pluckers must have realized that their own position had been revealed. Their only choice was to shroud themselves in slow fog so that they would appear perfectly safe and no one would bother them.

  But they hadn’t. Maybe they didn’t have the ability? But more than sufficient time had passed from the time they could pluck their star to send out a primitive membrane message for them to possess this ability.

  Perhaps they didn’t want to shroud themselves.

  If that was so, that made the Star-Pluckers very dangerous; far more dangerous than the dead world.

  Hide yourself well; cleanse well.

  Singer gazed at the world of the Star-Pluckers. It was an ordinary star that had at least a billion more time grains of life left. It possessed eight planets: four giant liquid planets and four solid ones. Singer’s experience told him that the low-entropy entities who had sent out the primitive membrane broadcast lived on one of the solid planets.

  Singer activated the process for the big eye—he rarely did this; he was exceeding his authority.

  “What are you doing?” asked the seed’s Elder. “The big eye is busy.”

  “I’d like to take a closer look at one of the low-entropy worlds.”

  “Your job doesn’t require close-up examinations.”

  “I’m just curious.”

  “The big eye has to observe more important targets. There’s no time for your curiosity. Go back to doing your job.”

  Singer didn’t persist in his request. The cleansing agent had the lowest position on the seed. Everyone thought of him contemptuously, thought of his work as easy and trivial. But they forgot that coordinates that had been broadcast often indicated far more danger than the vast majority who kept themselves well hidden.

  The only thing left was cleansing. Singer took a mass dot out of the magazine again, then realized that he couldn’t use a mass dot to cleanse the Star-Pluckers. Their planetary system had a different structure than the dead world’s system: it possessed blind corners. Using a mass dot might leave something behind, thereby wasting effort. He needed to use a dual-vector foil. However, Singer didn’t have the authority to retrieve a dual-vector foil out of the magazine; he had to ask the Elder for approval.

  “I need a dual-vector foil for cleansing.”

  “Permission granted,” said the Elder.

  The dual-vector foil drifted in front of Singer. It was sealed in its package, crystal clear. Although it was an ordinary object, Singer liked it a lot. He didn’t like the expensive tools too much; they were too violent. He liked the unyielding tenderness displayed by the dual-vector foil, a kind of aesthetic that could turn death into a song.

  Yet Singer felt a bit uneasy. “Why did you give it to me without so much as asking a question?”

  “It’s not like this is very costly.”

  “But if we make too much use of this—”

  “It’s being used everywhere in the cosmos.”

  “Yes, that is true. But in the past, we’ve always been restrained. Now—”

  “Have you heard something?” The Elder began to riffle through Singer’s thoughts, and Singer shuddered. Very quickly, the Elder found the rumor in Singer’s mind. It wasn’t a great sin—the rumor was an open secret on the seed.

  It was a rumor about the war between the home world and the fringe world. Before, news about the war had been frequent, but then the reports stopped, indicating that the war wasn’t going well, perhaps even heading into a crisis. But the home world couldn’t coexist wit
h the fringe world. The fringe world had to be destroyed, lest the home world be destroyed by it. If the war couldn’t be won, then …

  “Has the home world decided to transform into two dimensions?” Singer asked. Of course, the Elder already knew the question.

  The Elder did not answer, which was also an answer.

  If the rumor was true, then it was a great sorrow. Singer couldn’t imagine such a life. On the tower of values, survival ranked above all. When survival was threatened, all low-entropy entities could only pick the lesser of two evils.

  Singer removed these thoughts from his organ of cogitation. These were not thoughts he should have, and he was only going to be uselessly troubled by them. He tried to remember where he had stopped in his song. It took a while before he found his place. He continued to sing:

  Lovely markings are carved into time

  As soft to the touch as the mud in shallow sea.

  She covers her body with time,

  And pulls me along to fly to the edge of existence.

  This is a spiritual flight:

  In our eyes, the stars appear as ghosts;

  In the eyes of the stars, we appear as ghosts.

  As he continued to sing, Singer picked up the dual-vector foil with a force field feeler and carelessly tossed it at the Star-Pluckers.

  Bunker Era, Year 67

  Halo

  Cheng Xin awakened to find herself in weightlessness.

  Hibernation wasn’t like regular sleep. A hibernator didn’t feel the passage of time. Throughout the entire process, one could only feel time during the hour spent entering hibernation and the hour emerging from it. No matter how much time passed during hibernation, subjectively, the hibernator only felt that he or she had slept no more than two hours. Thus, waking up always involved a sharp break, a feeling that the self had passed through a door in time and emerged into a new world.