To Hold Up the Sky

by Cixin Liu

  Bigtooth straightened. “Esteemed god, the Devouring Empire will complete preparations for battle tonight!” he said solemnly.

  “Good, very good, the coming days will be interesting. But before all else, let us finish this gourd.” Li Bai nodded happily as he took up the gourd and poured the remaining wine. He looked at the river, now shrouded in night, and continued to savor those words: “A fine poem indeed, the first, haha, the first and already so fine.”

  THE ULTIMATE POETRY COMPOSITION

  The poetry-composition software was in fact very simple. Represented in humanity’s C language, it would be no more than two thousand lines of code, with an additional database of modest size appended storing the Chinese characters. Once the software was uploaded onto the quantum computer in the orbit of Neptune, an enormous transparent cone floating in the vacuum, the ultimate poetry composition began.

  Only now did the Devouring Empire learn that the god version of Li Bai was merely one individual member of his ultra-advanced civilization. The dinosaurs had previously assumed that any society that had advanced to this level of technology would have melded their consciousness into one being long ago; all five of the ultra-advanced civilizations they’d met in the past ten million years had done so. That Li Bai’s race had preserved their individual existences also somewhat explained their extraordinary ability to grasp art. When the poetry composition began, more individuals from Li Bai’s race jumped into the solar system from various places in distant space and began construction on the storage device.

  The humans living in the Devouring Empire couldn’t see the quantum computer in space, or the new arrivals from the race of gods. To them, the process of the ultimate poetry composition was simply the increase and decrease of the number of suns in space.

  One week after the poetry software began execution, the gods successfully extinguished the sun, reducing the sun count to zero. But the cessation of nuclear fission inside the sun caused the star’s outer layer to lose support, and it quickly collapsed into a new star that illuminated the darkness once more. However, this sun’s luminosity was a hundred times greater than before; smoke rose from the grass and trees on the surface of the Devouring Empire. The new star was once again extinguished, but a while later it burst alight again. So it went on, lighting only to be extinguished, extinguishing only to light once more, as if the sun were a cat with nine lives, struggling stubbornly. But the gods were highly practiced at killing stars. They patiently extinguished the new star again and again, until its matter had, as much as possible, fused into the heavier elements needed in the construction of the storage device. Only after the eleventh star dimmed was the sun snuffed out for good.

  At this point, the ultimate poetry composition had run for three Earth months. Long before then, during the appearance of the third new star, other suns had appeared in space. These suns rose and fell in succession throughout space, brightening and dimming. At one point, there were nine new suns in the sky. They were releases of energy as the gods dismantled the planets. With the star-sized sun diminishing in brightness later on, people could no longer tell the suns apart.

  The dismantlement of the Devouring Empire commenced the fifth week after the start of the poetry composition. Before it, Li Bai had made a suggestion to the Empire: The gods could jump all the dinosaurs to a world on the other side of the Milky Way. The civilization there was much less advanced than the gods’, its members being unable to convert themselves into pure energy, but still much more advanced than the Devourers’ civilization. There, the dinosaurs would be raised as a form of livestock and live happy lives with all their needs taken care of. But the dinosaurs would rather break than bend, and angrily refused this suggestion.

  Next, Li Bai made another request: that humanity be allowed to return to their mother planet. To be sure, Earth had been dismantled, and most of it went toward the storage device. But the gods saved a small amount of matter to construct a hollow Earth, about the same size as the original, but with only a hundredth of its mass. To say that the hollow Earth was Earth hollowed-out would be incorrect, because the layer of brittle rock that originally covered the Earth could hardly be used to make the spherical shell. The shell material was perhaps taken from the Earth’s core. In addition, razor-thin but extremely strong reinforcing hoops crisscrossed the shell, like lines of latitude and longitude, made from the neutronium produced in the collapse of the sun.

  Movingly, the Devouring Empire not only immediately agreed to Li Bai’s request, allowing all humans to leave the great ring world, but also returned the seawater and air they’d taken from Earth in their entirety. The gods used them to restore all of Earth’s original continents, oceans, and atmosphere inside the hollow Earth.

  Next, the terrible battle to defend the great ring began. The Devouring Empire launched barrages of nuclear missiles and gamma rays at the gods in space, but these were useless against their foe. The gods launched a powerful, invisible force that pushed at the Devourers’ ring, spinning it faster and faster, until it finally fell apart under the centrifugal forces of such rapid rotation. At this time, Yi Yi was en route to the hollow Earth. From twelve million kilometers away, he witnessed the complete course of the Devouring Empire’s destruction:

  The ring came apart very slowly, dreamlike. Against the pitch-black backdrop of space, this immense world dispersed like a piece of milk foam on coffee, the fragments at its edges slowly sinking into darkness, as if being dissolved by space. Only by the flashes of sporadic explosions would they reappear.

  Excerpt from Devourer

  The great, fierce civilization from ancient Earth was thus destroyed, to Yi Yi’s deepest lament. Only a few dinosaurs survived, returning to Earth with humanity, including the emissary Bigtooth.

  On the return journey to Earth, the humans were largely in low spirits, but for different reasons than Yi Yi: Once they were back on Earth, they’d have to farm and plow if they wanted to eat. To humans accustomed to having every need provided for in their long captivity, grown indolent and ignorant of labor, it really did seem like a nightmare.

  But Yi Yi believed in Earth’s future. No matter how many challenges lay ahead, humans were going to become people once more.

  THE CLOUD OF POEMS

  The poetry voyage arrived on the shores of Antarctica.

  The gravity here was already weak; the waves cycled slowly in a dreamlike dance. Under the low gravity, the impact of waves upon shore sent spray dozens of meters into the air, where the seawater contracted under surface tension into countless spheres, some as large as soccer balls, some as small as raindrops, which fell so slowly that one could draw rings around them with one’s hand. They refracted the rays of the little sun, so that when Yi Yi, Li Bai, and Bigtooth disembarked, they were surrounded by crystalline brilliance.

  Due to the forces of rotation, the Earth was slightly stretched at the North and South Poles, causing the hollow Earth’s pole regions to maintain their old chilly state. Low-gravity snow was a wonder, loose and foamy, waist-high in the shallow parts and deep enough at others that even Bigtooth disappeared beneath it. But having disappeared, they could still breathe normally inside the snow! The entire Antarctic continent was buried underneath this snow-foam, creating an undulating landscape of white.

  Yi Yi and company rode a snowmobile toward the South Pole. The snowmobile skimmed across the snow-foam like a speedboat, throwing waves of white to either side.

  The next day, they arrived at the South Pole, marked by a towering pyramid of crystal, a memorial dedicated to the Earth Defense War of two centuries ago. Neither writing nor images marked its surface. There was just the crystal form in the snow-foam at the apex of the Earth, silently refracting the sunlight.

  From here, one could gaze upon the entire world. Continents and oceans surrounded the radiant little sun, so that it looked as if it had floated up from the waters of the Arctic Sea.

  “Will that little sun really be able to shine forever?” Yi Yi asked Li Bai. />
  “At the very least, it will last until the new Earth civilization is advanced enough to create a new sun. It is a miniature white hole.”

  “White hole? Is that the inverse of a black hole?” asked Bigtooth.

  “Yes, it’s connected through a wormhole to a black hole orbiting a star, two million light-years away. The black hole sucks in the star’s light, which is released here. Think of the sun as one end of a fiber-optic cable running through hyperspace.”

  The apex of the monument was the southern starting point of the Lagrangian axis, the thirteen-thousand-kilometer line of zero gravity between the North and South Poles of the hollow Earth, named after the zero-gravity Lagrangian point that had existed between the Earth and moon before the war. In the future, people were certain to launch various satellites onto the Lagrangian axis. Compared to the process on Earth before the war, this would be easy: one would only have to ship the satellite to the North or South Pole, by donkey if one wanted to, and give it a good kick up with one’s foot.

  As the party viewed the memorial, another, larger snowmobile ferried over a crowd of young human tourists. After disembarking, the tourists bent their legs and jumped straight into the air, flying high along the Lagrangian axis, turning themselves into satellites. From here, one could see many small, black specks in the air, marking out the position of the axis: tourists and vehicles drifting in zero gravity. They would have been able to fly directly to the North Pole if it weren’t for the sun, placed at the midpoint of the Lagrangian axis. In the past, some tourists flying along the axis had discovered their handheld miniature air-jet thrusters broken, been unable to decelerate, and flown straight into the sun. Well, in truth, they vaporized a considerable distance from it.

  In the hollow Earth, entering space was also easy. One only needed to jump into one of the five deep wells on the equator (called Earthgates) and fall (fly?) a hundred kilometers through the shell, then be flung by the centrifugal forces of the hollow Earth’s rotation into space.

  Yi Yi and company also needed to pass through the shell to see the Cloud of Poems, but they were heading through the Antarctic Earthgate. Here, there were no centrifugal forces, so instead of being flung into space, they would only reach the outer surface of the hollow Earth. Once they’d put on lightweight space suits at the Antarctic control station, they entered the one-hundred-kilometer well—although, without gravity, it was better termed a tunnel. Being weightless here, they used the thrusters on their space suits to move forward. This was much slower than the free fall on the equator; it took them half an hour to arrive on the outside.

  The outer surface of the hollow Earth was completely barren. There were only the crisscrossing reinforcing hoops of neutronium, which divided the outside by latitude and longitude into a grid. The South Pole was indeed where all the longitudinal hoops met. When Yi Yi and company walked out of the Earthgate, they saw that they were located on a modestly sized plateau. The hoops that reinforced Earth resembled many long mountain ranges, radiating in every direction from the plateau.

  Looking up, they saw the Cloud of Poems.

  In place of the solar system was the Cloud of Poems, a spiral galaxy a hundred astronomical units across, shaped much like the Milky Way. The hollow Earth was situated at the edge of the Cloud, much as the sun had been in the actual Milky Way. The difference was that Earth’s position was not coplanar with the Cloud of Poems, which allowed one to see one face of the Cloud head-on, instead of only edge-on as with the Milky Way. But Earth wasn’t nearly far enough from the plane to allow people here to observe the full form of the Cloud of Poems. Instead, the Cloud blanketed the entire sky of the southern hemisphere.

  The Cloud of Poems emitted a silvery radiance bright enough to cast shadows on the ground. It wasn’t that the Cloud itself was made to glow, apparently, but rather that cosmic rays would excite it into silver luminescence. Due to the uneven spatial distribution of the cosmic rays, glowing masses frequently rippled through the Cloud of Poems, their varicolored light rolling across the sky like luminescent whales diving through the Cloud. Rarely, with spikes in the cosmic radiation, the Cloud of Poems emitted dapples of light that made the Cloud look utterly unlike a cloud. Instead, the entire sky seemed to be the surface of a moonlit sea seen from below.

  Earth and the Cloud did not move in sync, so sometimes Earth lay in the gaps between the spiral arms. Through the gap, one could see the night sky and the stars, and most thrillingly, a cross-sectional view of the Cloud of Poems. Immense structures resembling Earthly cumulonimbuses rose from the spiraling plane, shimmering with silvery light, morphing through magnificent forms that inspired the human imagination, as if they belonged to the dreamscape of some super-advanced consciousness.

  Yi Yi tore his gaze from the Cloud of Poems and picked up a crystal chip off the ground. These chips were scattered around them, sparkling like shards of ice in winter. Yi Yi raised the chip against a sky thick with the Cloud of Poems. The chip was very thin, and half the size of his palm. It appeared transparent from the front, but if he tilted it slightly, he could see the bright light of the Cloud of Poems reflect off its surface in rainbow halos. This was a quantum memory chip. All the written information created in human history would take up less than a millionth of a percent of one chip. The Cloud of Poems was composed of 1040 of these storage devices, and contained all the results of the ultimate poem composition. It was manufactured using all the matter in the sun and its nine major planets, of course including the Devouring Empire.

  “What a magnificent work of art!” Bigtooth sighed sincerely.

  “Yes, it’s beautiful in its significance: a nebula fifteen billion kilometers across, encompassing every poem possible. It’s too spectacular!” Yi Yi said, gazing at the nebula. “Even I’m starting to worship technology.”

  Li Bai gave a long sigh. He had been in a low mood all this time. “Ai, it seems like we’ve both come around to the other person’s viewpoint. I witnessed the limits of technology in art. I—” He began to sob. “I’ve failed.…”

  “How can you say that?” Yi Yi pointed at the Cloud of Poems overhead. “This holds all the possible poems, so of course it holds the poems that surpass Li Bai’s!”

  “But I can’t get to them!” Li Bai stomped his foot, which shot him meters into the air. He curled into a ball in midair, miserably burying his face between his knees in a fetal position; he slowly descended under the weak gravitational pull of the Earth’s shell. “At the start of the poetry composition, I immediately set out to program software that could analyze poetry. At that point, technology once again met that unsurpassable obstacle in the pursuit of art. Even now, I’m still unable to write software that can judge and appreciate poetry.” He pointed up at the Cloud of Poems. “Yes, with the help of mighty technology, I’ve written the ultimate works of poetry. But I can’t find them amid the Cloud of Poems, ai…”

  “Is the soul and essence of intelligent life truly untouchable by technology?” Bigtooth loudly asked the Cloud of Poems above. He’d become increasingly philosophical after all he’d endured.

  “Since the Cloud of Poems encompasses all possible poems, then naturally some portion of those poems describes all of our pasts and all of our futures, possible and impossible. The bug-bug Yi Yi would certainly find a poem that describes how he felt one night thirty years ago while clipping his fingernails, or a menu from a lunch twelve years in his future. Emissary Bigtooth, too, might find a poem that describes the color of a particular scale on his leg five years from now.…”

  Li Bai had touched down once more on the ground; as he spoke, he took out two chips, shimmering under the light of the Cloud of Poems. “These are my parting gifts for you two. The quantum computer used your names as keywords to search through the Cloud of Poems, and found several quadrillion poems that describe your various possible future lives. Of course, these are only a tiny portion of the poems with you as subject in the Cloud of Poems. I’ve only read a couple dozen of these. My favorite i
s a seven-character-line poem about Yi Yi describing a romantic riverbank scene between him and a beautiful woman from a faraway village.…

  “After I leave, I hope humanity and the remaining dinosaurs can get along with each other, and that humanity can get along with itself even better. If someone nukes a hole into the shell of the hollow Earth, it’s going to be a real problem.… The good poems in the Cloud of Poems don’t belong to anyone yet. Hopefully humans will be able to write some of them.”

  “What happened to me and the woman, afterward?” Yi Yi asked.

  Under the silver light of the Cloud of Poems, Li Bai chuckled. “Together, you lived happily ever after.”

  THE THINKER

  TRANSLATED BY JOHN CHU

  THE SUN

  He still remembered how he felt the first time he saw the Mount Siyun Astronomical Observatory thirty-four years ago. After his ambulance crossed the mountain ridge, Mount Siyun’s highest peak emerged in the distance. Its observatories’ spherical roofs reflected the golden light of the setting sun like pearls inlaid into the mountain peak.

  At the time, he’d just graduated from medical school. A brain-surgery intern assisting the chief of surgery, he’d been rushed here to save a visiting research scholar from England who’d fallen on a hike. The scholar had injured his head too seriously to be moved. Once the ambulance arrived, they drilled a hole in the patient’s skull, then drained some blood out to reduce brain swelling. Once the patient had been stabilized enough to move, the ambulance took him to the hospital for surgery.

  It was late at night by the time they could leave. Out of curiosity, while others carried the patient into the ambulance, he examined the several spherical observatories that surrounded him. How they were laid out seemed to imply some sort of hidden message, like a Stonehenge in the moonlight. Spurred on by some mystical force that he still didn’t understand even after a lifetime of contemplation, he walked to the nearest observatory, opened its door, then walked inside.