Death's End

by Liu Cixin

  “I thought you could move the exit of the mini-universe at lightspeed,” Yifan said. “Can’t you move it around to find a habitable location?”

  “If you insist, I will try. But I still think staying here is the best choice. There are two possible futures if you remain: If the Returners succeed in their mission, the great universe will collapse into a singularity and lead to a new big bang so that we can go to the new universe. But if the Returners fail and the great universe dies, you can live out the rest of your lives in this mini-universe. This isn’t too bad.”

  “If everyone in every mini-universe thinks that way,” said Cheng Xin, “then they will have doomed the great universe.”

  Sophon gazed at Cheng Xin wordlessly. Given the speed of Sophon’s thought, perhaps this period of time felt as long as several centuries to her. It was hard to imagine that software and algorithms could produce such a complex expression. Perhaps Sophon’s AI software had brought up all the memories accumulated across almost twenty million years since she had met Cheng Xin. All these memories seemed to precipitate in her gaze: sorrow, admiration, surprise, reproach, regret … so many complicated feelings mixed together.

  “You’re still living for your responsibility,” Sophon said.

  Excerpt from A Past Outside of Time

  The Stairs of Responsibility

  All my life has been spent climbing up a flight of stairs made of responsibility.

  When I was little, my only duty was to study hard and obey my parents.

  Later, in high school and college, the responsibility to study hard continued, but there was also the added obligation to make myself useful rather than a drain on society.

  By the time I started to work toward my doctorate, my responsibilities became more concrete. I needed to contribute to the development of chemical rockets, to build more powerful, more reliable rockets so that more materials and a few men and women could be sent into Earth orbit.

  Later, I joined the PIA, and my responsibility was to send a probe into space a light-year away to meet the invading Trisolaran Fleet. This was a distance about ten billion times greater than the distance I had worked with as a rocket engineer.

  And then, I received a star. During the new era, it brought me previously unimaginable responsibilities. I became the Swordholder, whose duty was to maintain dark forest deterrence. Looking back on it now, perhaps it was a bit of an exaggeration to claim that I held the fate of humankind; but I really did control the direction of development for two civilizations.

  Later, my responsibilities became more complicated: I wanted to endow humans with lightspeed wings, but I also had to thwart that goal to prevent a war.

  I don’t know how much those catastrophes and the final destruction of the Solar System had to do with me. Those are questions that could never be answered definitively. But I’m certain they had something to do with me, with my responsibilities.

  And now, I’ve climbed to the apex of responsibility: I am responsible for the fate of the universe. Of course this responsibility doesn’t belong only to me and Guan Yifan, but we own a share of the responsibility, a share of something that I never could have imagined.

  I want to tell all those who believe in God that I am not the Chosen One. I also want to tell all the atheists that I am not a history-maker. I am but an ordinary person. Unfortunately, I have not been able to walk the ordinary person’s path. My path is, in reality, the journey of a civilization.

  And now we know that this is the journey that must be made by every civilization: awakening inside a cramped cradle, toddling out of it, taking flight, flying faster and farther, and, finally, merging with the fate of the universe as one.

  The ultimate fate of all intelligent beings has always been to become as grand as their thoughts.

  Outside of Time

  Our Universe

  Through Universe 647’s control system, Sophon managed to move the mini-universe’s exit inside the great universe. The door moved quickly through the great universe, searching for a habitable world. The amount of information that the door could transmit to the mini-universe was very limited, and no images or videos were possible. All that could be sent back was a rough analysis of the environment. This was a number between negative ten and ten, indicating the habitability of the environment. Humans could survive only if the number were greater than zero.

  The door jumped tens of thousands of times in the great universe. After three months, only once did they discover a habitable planet, with a rating of three. Sophon had to concede that this was probably the best result they could get.

  “A rating of three indicates a dangerous and inhospitable world,” Sophon warned.

  “We’re not afraid,” said a resolute Cheng Xin. Yifan nodded. “Let’s go there.”

  The door appeared in Universe 647. Like the door Cheng Xin and Guan Yifan had seen on Planet Blue, it was also a rectangle limned by glowing lines. But this door was much bigger, perhaps to make it easier to transport material through it. Initially, the door was not connected to the great universe, and anything could pass through it without leaving the mini-universe. Sophon adjusted its parameters so that anything moving through it would disappear and reappear in the great universe.

  Next, it was time to return matter from the mini-universe to the great universe.

  Sophon had explained that the mini-universe had no matter of its own. All of its mass had come from material brought out of the great universe. Of the several hundred mini-universes constructed by the Trisolarans, Universe 647 was one of the smallest. In total, it required about five hundred thousand metric tons of matter from the great universe, which was about the carrying capacity of a large oil tanker. It was practically nothing at the scale of the universe.

  They began with the soil. After the last harvest, the field had been left fallow. The robots used a wheelbarrow to cart the moist earth; at the door, two of the robots lifted the wheelbarrow to dump the soil through the door; and the soil disappeared. It happened very quickly. Three days later, all the soil in the mini-universe was gone. Even the trees around the house had been returned through the door.

  With all the soil removed, they saw the metallic floor of the mini-universe. The floor was pieced together with smooth metal tiles that reflected the sun like a mirror. The robots took off the metal tiles one by one and sent them through the door as well.

  Underneath the floor was a small spaceship. Although the ship was less than twenty meters long, it contained the most advanced technologies of the Trisolarans. Designed with human occupants in mind, it could seat three, and was equipped with both a nuclear fusion drive and a curvature drive. There was a miniature ecological cycling system aboard suitable for human needs as well as equipment for hibernation. Like Halo, it was capable of landing and taking off from planetary surfaces. It had a slender, streamlined profile, perhaps to make it easier to go through the mini-universe’s door. It had been intended for the inhabitants of Universe 647 to enter the new great universe after the next big bang. It could serve as a living base for a considerable amount of time, until they found a suitable location in the new universe. But now, they would use it to return to the old great universe.

  As the rest of the metal floor tiles were removed, they also revealed more machinery beneath. These were the first objects Cheng Xin and Guan Yifan had seen in the mini-universe that bore obvious signs of being of Trisolaran origin. Like Cheng Xin had suspected, the design of these machines evinced an aesthetic completely different from human ideals. Cheng Xin and Guan Yifan couldn’t even tell at first that they were looking at machinery; rather, the objects resembled strange sculptures or natural geologic formations. The robots began to disassemble the machinery and send the pieces through the door.

  Cheng Xin and Sophon busied themselves in a room and wouldn’t let Yifan in. They said that they were working on a “women’s project” and would surprise him later.

  After some machine under the floor was shut off, gravity disappeared fr
om the mini-universe. The white house began to float in air.

  The weightless robots disassembled the sky, which was a thin membrane capable of displaying a blue sky and white clouds. Finally, the remnants of the floor below the machinery were also disassembled and sent away.

  The water in the mini-universe had evaporated and fog was everywhere. The sun shone from behind a veil of clouds and a spectacular rainbow appeared that crossed from one end of the universe to the other. Whatever liquid water was left in the mini-universe formed spheres of various sizes and drifted around the rainbow, reflecting and refracting sunlight.

  Disassembling the machines also meant turning off the ecological cycling system. Cheng Xin and Yifan had to put on space suits.

  Sophon adjusted the parameters in the door again to allow gas through. A low rumble shook the mini-universe, caused by air escaping through the door. Below the rainbow, the white fog cloud formed a great maelstrom around the door, like a view of a typhoon from space. And then, the whirling fog turned into a tornado, and let out a high-pitched howl. The drifting balls of water were sucked into the twister, torn apart, and disappeared through the door. Countless small objects drifting in the air were also swallowed up by the cyclone. The sun, the house, the spaceship, and other large objects also drifted in the direction of the door, but robots equipped with thrusters quickly secured them back in place.

  As the air thinned, the rainbow disappeared, and the fog dissipated. The air became more transparent, and gradually, the mini-universe’s space appeared. Like space in the great universe, it was also dark and deep, but there were no stars. Only three objects floated in space: the sun, the house, and the spaceship, along with about a dozen weightless robots. In Cheng Xin’s eyes, this simplified world resembled the naïve, clumsy pictures she had drawn in her childhood.

  Cheng Xin and Guan Yifan activated the thrusters on their space suits and flew toward the depths of space. After a kilometer, they reached the end of the universe and, in a flash, found themselves back where they had started. They could see the projected images of every floating object repeated endlessly in every direction. Like two mirrors placed against each other, the images extended in rows into infinity.

  The house was disassembled. The last room to be taken apart was the parlor decorated in an Eastern style in which Sophon had welcomed them. All the scrolls, the tea table, and the pieces of the house were sent out the door by the robots.

  The sun finally went out. It was a metal sphere where one hemisphere, the part that had emitted light, was transparent. Three robots pushed it through the door. Only lamps now illuminated the mini-universe, and the vacuum that was space soon cooled. What was left of the water and air soon turned into ice fragments that sparkled in the lamplight.

  Sophon directed the robots to line up and go through the door, one after the other.

  Finally, only the slender ship was left in the mini-universe, along with three figures drifting near it.

  Sophon held a metal box. This box would be left behind in the mini-universe, a message in a bottle for the new universe that would be born after the next big bang. The box contained a miniature computer whose quantum memory held all the information in the mini-universe’s computer—this was practically the entire memory of the Trisolaran and Earth civilizations. After the birth of the new universe, the metal box would receive a signal from the door, and it would go through the door using its own tiny thrusters and enter the new universe. It would drift through the high-dimensional space of the new universe until the day it was picked up and read. At the same time, it would continuously broadcast its message using neutrinos—assuming the new universe also had neutrinos.

  Cheng Xin and Guan Yifan believed that in the other mini-universes, at least those mini-universes that heeded that call of the Returners, the same things were being done. If the new universe were really born, it would contain many bottles containing messages drifting through it. It was believable that a considerable number of bottles contained storage mechanisms that held the memories and thoughts of every individual of that civilization, as well as their complete biological details—maybe the records would be sufficient for a new civilization in the new universe to revive that old civilization.

  “Can we keep another five kilograms here?” Cheng Xin asked. She was on the other side of the ship and dressed in her space suit. In her hand, she held a glowing, transparent sphere. The sphere was about half a meter in diameter, and a few balls of water drifted inside it. Inside some of the water spheres were tiny fish, along with green algae. There were also two miniature drifting continents covered with green grass. The light came from the top of the transparent sphere, where there was a tiny glowing emitter, the sun of this miniature world. This was a completely sealed ecological sphere, the result of more than ten days of work by Cheng Xin and Sophon. As long as the tiny sun inside the sphere continued to give off light, this miniature ecological system would persist. As long as it remained here, Universe 647 would not be a lifeless, dark world.

  “Of course,” said Guan Yifan. “The great universe isn’t going to fail to collapse because it misses five kilograms.” He had another thought that he did not voice: Perhaps the great universe really would fail to collapse because it lacked a single atom’s mass. The precision of Nature can sometimes exceed the imagination. For instance, life itself required the precise collaboration of various universal constants within a billion-billionth of a certain range. But Cheng Xin could still leave behind her ecological sphere. Out of all the countless mini-universes created by the countless civilizations, it was certain that some number of them would not heed the call of the Returners. Ultimately, the great universe was certain to lose at least a few hundred million tons of matter, or perhaps even a million billion billion tons.

  Hopefully, the great universe could ignore such a loss.

  Cheng Xin and Guan Yifan entered the spaceship, and Sophon came in last. She had long ceased wearing her magnificent kimono and turned once again into that lean and nimble warrior dressed in camouflage. She had all sorts of weapons and survival gear strapped to her body, the most prominent being the katana on her back.

  “Don’t worry,” she said to her two human friends. “As long as I’m alive, no harm will come to you.”

  The fusion drive activated and the thrusters emitted a dim blue light. The spaceship slowly went through the door of the universe.

  * * *

  The message in a bottle and the ecological sphere were the only things left in the mini-universe. The bottle faded into the darkness so, in this one-cubic-kilometer universe, only the little sun inside the ecological sphere gave off any light. In this minuscule world of life, a few clear watery spheres drifted serenely in weightlessness. One tiny fish leapt out of a watery sphere and entered another, where it effortlessly swam between the green algae. On a blade of grass on one of the miniature continents, a drop of dew took off from the tip of the grass blade, rose spiraling into the air, and refracted a clear ray of sunlight into space.

  TRANSLATOR’S POSTSCRIPT

  I’m indebted to the following beta readers for their invaluable help during the translation process: Anatoly Belilovsky, John Chu, Elías Combarro, Rachel Cordasco, Derwin Mak, Alex Shvartsman, and Igor Teper. All translators should be so lucky.

  I’m also thankful for special assistance from the following individuals: Wang Meizi, for advice on transliterated names; Anna Gustafsson Chen, for pointers on Scandinavian geography; and Emma Osborne, for tracking down books for me on the other side of the globe.

  My heartfelt gratitude goes to David Brin for championing the Three-Body series and acting as a wonderful sounding board for me.

  I continue to be awed by the genius of Liu Cixin every time I read another passage from this novel. Of the three books in the trilogy, this third one is my favorite. I’ve been very fortunate to get the chance to work on this book with Da Liu.

  Finally, I want to thank the many individuals who played indispensable (though often unde
rappreciated) roles in the epic tale of bringing Three-Body to the English-speaking world: Li Yun and Song Yajuan at China Educational Publications Import & Export Corporation Ltd., for seeing the potential of a global audience for the series and commissioning the translation; Joel Martinsen, who translated The Dark Forest and, by example, showed me how to handle some tricky parts in this book; Emily Jiang, Wang Meizi, and Chen Qiufan, for building the bridge that connected Tor Books to Liu Cixin; Joe Monti, for encouraging me to take on this project in the first place; and the many wonderful individuals at Tor Books who worked so hard to make the vision of these books a reality. Among them are: Irene Gallo, Stephan Martinière, and Jamie Stafford-Hill, for extraordinary art direction, artwork, and cover design; Leah Withers and Diana Griffin, for an outstanding publicity campaign; Joe Bendel for his sales and marketing insight; Kevin Sweeney, Heather Saunders, Nathan Weaver, Karl Gold, and Megan Kiddoo, from Tor’s production department; Christina MacDonald, who ensured that errors and bugs would not survive in the manuscript; Miriam Weinberg, for assisting with editorial matters; and most of all, Liz Gorinsky, who left an indelible mark on the text with her meticulous and insightful editorial touch, improving this translation in innumerable ways. I hope to continue to make beautiful books with them all in the future.

  TOR BOOKS BY CIXIN LIU

  The Three-Body Problem

  The Dark Forest

  Death’s End

  ABOUT THE AUTHOR

  Cixin Liu is the most popular science fiction writer in the People’s Republic of China. Liu is a winner of the Hugo Award and a multiple winner of the Galaxy and Xingyun (Nebula) Awards, China’s two highest honors for speculative fiction. Prior to becoming a writer, he worked as an engineer in a power plant in Yangquan, Shanxi. You can sign up for email updates here.