To Hold Up the Sky

by Cixin Liu

  “How are we hearing your voice?” the US president asked.

  “I am emitting superstring waves into your atmosphere.”

  “Superstring waves?”

  “A strong interactive force released from an atomic nucleus. It excites your atmosphere like a giant hand beating a drum. That’s how you hear me.”

  “Where do you come from?” the secretary general asked.

  “I am a mirror drifting through the universe. I originate so far away in both time and space it is meaningless to speak of it.”

  “How did you learn English?”

  “I said that I see all. I should note that I’m speaking English because most of the audience at this concert was conversing in that language, not because I believe any ethnic group on the world below is superior to any other. It’s all I can do when there’s no global common tongue.”

  “We do have a world language, but it is little used.”

  “Your world language? Less an effort toward world unity than a classic expression of chauvinism. Why should a world language be Latinate rather than based on some other language family?”

  This caused a commotion among the world leaders, who whispered nervously to each other.

  “We’re surprised at your understanding of Earth culture,” the secretary general said earnestly.

  “I see all. Besides, a thorough understanding of a speck of dust isn’t hard.”

  The US president looked up at the sky and said, “Are you referring to the Earth? You may be bigger, but on a cosmic scale you’re on the same order as the Earth. You’re a speck of dust, too.”

  “You’re less than dust,” the mirror said. “A long, long time ago I used to be dust, but now I’m just a mirror.”

  “Are you an individual or a collective?” the Chinese president asked.

  “That question is meaningless. When a civilization travels far enough on the road of time, individual and collective both disappear.”

  “Is a mirror your intrinsic form, or one of your many expressions?” the UK prime minister asked.

  The secretary general added, “In other words, are you deliberately exhibiting this form for our benefit?”

  “This question is also meaningless. When a civilization travels far enough on the road of time, form and content both disappear.”

  “We don’t understand your answers to the last two questions,” the US president said.

  The mirror said nothing.

  Then the secretary general asked the key question: “Why have you come to the solar system?”

  “I am a musician. A concert is being held here.”

  “Excellent,” the secretary general said with a nod. “And humanity is the audience?”

  “My audience is the entire universe, even if it will be a century before the nearest civilized world hears my playing.”

  “Playing? Where’s your instrument?” Richard Clayderman asked from the stage.

  They realized the reflected Earth covering most of the sky had begun to slip swiftly toward the east. The change was frightening, like the sky falling, and a few people on the lawn involuntarily buried their head in their hands. Soon the reflection’s edge dipped below the horizon, but at practically the same time, everything turned hazy in a sudden bright light. When sight returned, they saw the sun sitting smack in the middle of the sky right where the reflected Earth had been. Brilliant sunlight illuminated their surroundings under a brilliant blue sky that had replaced the black night. The oceans of the reflected Earth blended with the blue of the sky so the land seemed like a patch of clouds. They stared in shock at the change, but then a word from the secretary general explained the change that had taken place.

  “The mirror tilted.”

  Indeed, the huge mirror had tilted in space, drawing the sun into the reflection and casting its light onto the Earth’s nighttime side.

  “It rotates fast!” the Chinese president said.

  The secretary general nodded. “Yes, and at that size, the edges must be nearing the speed of light!”

  “No physical object can tolerate the stresses from that rotation. It’s a field, like our astronaut demonstrated. Near-light-speed motion is entirely normal for a field,” the US president said.

  Then the mirror spoke: “This is my instrument. I am a star player. My instrument is the sun!”

  These grand words silenced them all, and they stared mutely at the reflected sun for a long while before someone asked, their voice trembling with awe, how it was played.

  “You’re all aware that many of the instruments you play have a sound chamber whose thin walls reflect and confine sound waves, allowing them to resonate and produce pleasing sounds. In the case of EM waves, the chamber is a star—it may lack visible walls, but it has a transmission speed gradient that reflects and refracts the waves, confining them to produce EM resonance and play beautiful music.”

  “What does this instrument sound like?” Clayderman asked the sky.

  “Nine minutes ago, I played tuning notes on the sun. The instrument’s sound is now being transmitted at the speed of light. Of course, it’s in EM form, but I can convert it to sound in your atmosphere through superstring waves. Listen.…”

  They heard a few delicate, sustained notes, similar to those of a piano, but with a magic that held everyone momentarily under its spell.

  “How does the sound make you feel?” the secretary general asked the Chinese president.

  “Like the whole universe is a huge palace, one that’s twenty billion light-years tall. And the sound fills it completely.”

  “Can you still deny the existence of God after hearing that?” the US president asked.

  The Chinese president eyed him, and said, “The sound comes from the real world. If it can produce such a sound, then God is even less essential.”

  THE BEAT

  “Is the performance about to start?” the secretary general asked.

  “Yes. I’m waiting for the beat,” the mirror replied.

  “The beat?”

  “The beat began four years ago and is being transmitted here at the speed of light.”

  Then there was a fearsome change in the sky. The reflected Earth and sun disappeared, replaced by dancing bright silver ripples that filled the sky, making them feel like Earth had been plunged into an enormous ocean and they were looking up at the blazing sun beyond the water’s surface.

  The mirror explained: “I’m blocking intense radiation from outer space. I can’t totally reflect it, so what you’re seeing is the small portion that gets through. The radiation comes from a star that went supernova four years ago.”

  “Four years ago? That’s Centauri,” someone said.

  “That’s right. Proxima Centauri.”

  “But that star has none of the necessary conditions for supernova,” the Chinese president said.

  “I created the conditions,” the mirror said.

  They realized that when the mirror had said it made preparations for this concert four years ago, it was referring to that event; after selecting the sun as its instrument, it had detonated Proxima Centauri. Judging from the audio test of the sun, it was evidently capable of acting through hyperspace and pulsing the sun 1 AU away. But whether it possessed the same ability for a star four light-years away remained unknown. The detonation of Proxima Centauri could have been accomplished in one of two ways: from the solar system via hyperspace, or by teleporting to its vicinity, detonating it, and then teleporting back. Both were godlike power, so far as humanity was concerned, and in any case the light from the supernova would still take four years to reach to the sun. The mirror said that music it played would be transmitted to the cosmos by EM, so was the speed of light for that hypercivilization akin to the speed of sound for humans? And if light waves were their sound waves, what was light for them? Humanity would never know.

  “Your ability to manipulate the physical world is alarming,” the US president said.

  “Stars are stones in the cosmic desert
, the most commonplace of objects in my world. Sometimes I use stars as tools, other times as weapons, and other times as musical instruments.… I’ve turned Proxima Centauri into a metronome, basically the same as the stones used by your ancestors. We both take advantage of ordinary objects in our world to enlarge and extend our abilities.”

  But the occupants of the lawn could see no similarity between the two, and abandoned the attempt to discuss technology with the mirror. Humanity could no more comprehend it than an ant could understand the ISS.

  Little by little the light in the sky began to dim, giving them the impression that it was moonlight shining on the ocean, not sunlight, and that the supernova was going out.

  The secretary general said, “If the mirror hadn’t blocked the energy from the supernova, the Earth would be a dead planet.”

  By this point the ripples in the sky were gone, and the Earth’s enormous reflection again occupied most of the sky.

  “Where’s the beat?” Clayderman asked. He had left the stage and was sitting among the world leaders.

  “Look to the east!” someone shouted, and they saw in the eastern sky a dividing line, ramrod straight, bisecting the heavens into two distinct images. The reflected Earth, partially cut off, remained on the western side, but in the east was a dazzling starfield that many of them knew was the correct one for the northern hemisphere rather than the reflected southern sky. The division line marched west, enlarging the starry sky and wiping out the reflected Earth.

  “It’s flying away!” shouted the secretary general. And they realized he was right: the mirror was leaving the space over Earth. Its edge soon vanished beneath the western horizon, leaving them standing beneath the stars of an ordinary sky. It did not reappear—perhaps it had flown off to the vicinity of its sun instrument.

  It comforted them somewhat to see the familiar world, the stars and city lights as they had been, and to smell the blossoms wafting over the lawn.

  Then came the beat.

  Day arrived without warning with a sudden blue sky and blazing sunlight that flooded the land and lit up their surroundings with brilliant light. But daytime lasted but a second before extinguishing into renewed night as stars and city lights returned. And the night lasted only a second before day returned, only for a second, and then it was night again. Day, and then night, then day, then night … like a pulse, or as if the world were a projector switching back and forth between two slides.

  A beat formed out of night and day.

  They looked up and saw the flashing star, now just a blinding, dimensionless point of light in space. “A pulsar,” said the Chinese president.

  The remains of a supernova, a whirling neutron star, the naked hot spot on its dense surface turning it into a cosmic lighthouse, its revolution sweeping the beam emitted by its hot spot through space, and giving Earth a brief moment of daytime as it swept past the solar system.

  “I seem to recall,” the secretary general said, “that a pulsar’s frequency is far faster than this. And it doesn’t emit visible light.”

  Shielding his eyes with a hand and struggling to adjust to the crazy rhythm of the world, the US president said, “The high frequency is because the neutron star retains the former star’s angular momentum. The mirror may be able to somehow drain that momentum. As for visible light … do you really think that’s something the mirror can’t do?”

  “There’s another thing,” the Chinese president said. “There’s no reason to believe that the pace of life for all beings in the universe is like that of humanity. The beat for their music might be on a completely different frequency. The mirror’s normal beat, for example, may be faster than even our fastest computers.”

  “Yes,” the US president said, nodding. “And there’s no reason to believe that what they perceive as visible light is the same EM spectrum.”

  “So you’re saying that the mirror’s music is benchmarked to human senses?” the secretary general asked in surprise.

  The Chinese president shook his head. “I don’t know. But it’s got to be based on something.”

  The pulsar’s powerful beam swept across the empty sky like a four-trillion-kilometer-long baton, still growing at the speed of light. At this end, played on the sun by the mirror’s invisible fingers and transmitted to the cosmos at the speed of light, the sun concert began.

  SUN MUSIC

  A rustle like radio jamming or the endless pounding of waves on sand occasionally offered up hints of a vast desolation within its more abundant chaos and disorder. The sound went on for more than ten minutes without changing.

  The Russian president broke the silence: “Like I said, we can’t understand their music.”

  “Listen!” Clayderman said, pointing at the sky, but it was a long moment before the rest of them heard the melody his trained ears had picked out at once. A simple structure of just two notes, reminiscent of a clock’s tick-tock. The notes repeated, separated by lengthy gaps. Then another two-note section, and a third, and a fourth … paired tones emerging ceaselessly from the chaos like fireflies in the night.

  Then a new melody emerged, four notes. Everyone turned toward Clayderman, who was listening attentively and seemed to have sensed something. The four-note phrases multiplied.

  “Here,” he said to the heads of state. “Let’s each of us remember a two-note measure.” And so they all listened carefully, and each found a two-note measure and then focused their energy on committing it to memory. After a while, Clayderman said, “Very well. Now concentrate on a four-note phrase. Quickly, though, or else the music will grow too complex for us to pick them out.… Yes, that one. Does anyone hear that?”

  “The first half is the pair of notes I memorized!” called the head of Brazil.

  “The second half is my pair!” said the head of Canada.

  They realized that every four-note phrase was made up of two of the previous note pairs, and as the four-note phrases multiplied they seemed to be depleting the isolated pairs. Then came eight-note phrases, similarly formed out of sets of four-note phrases.

  “What do you hear?” the secretary general asked the people around him.

  “A primeval ocean lit by flashes of lightning and volcanoes, and small molecules combining into larger ones … of course, that’s purely my own imagination,” the Chinese president said.

  “Don’t constrain your imagination to the Earth,” the US president said. “The clustering of these molecules may be taking place in a nebula glowing with starlight. Or maybe they’re not molecules, but the nuclear vortices inside a star…”

  Then came a high-pitched, multi-note phrase that repeated like a bright spark in the dim chaos. “It’s like it’s describing a fundamental transformation,” the Chinese president said.

  Then they heard a new instrument, a sustained violin-like string sound that repeated a gentle shadow of the standout melody.

  “It’s expressing a kind of duplication,” the Russian president said.

  Now came an uninterrupted melody from the violin voice, changing smoothly as if it were light in curvilinear motion. The UK prime minister said to the Chinese president, “To borrow your idea, that ocean has something swimming in it now.”

  At some point the background music, which they’d nearly forgotten about, had begun to change. From the sound of waves it had turned into an oscillating rush, like a storm assaulting the bare rock. Then it changed again, into wind-like bleakness. The US president said, “The swimmer has entered a new environment. The land, or perhaps the air.”

  Then all the instruments played in unison for a brief moment, a fearsomely loud sound like an enormous physical collapse, then they abruptly dropped out, leaving just the lonely sound of the surf. Then the simple note pairs started up again and turned gradually complex, and everything repeated.…

  “I can say with certainty that a great extinction was just described, and now we’re listening to the revival afterward.”

  After another long and arduous process, the
ocean swimmer ventured again into other parts of the world. Slowly, the melody grew grander and more complicated, and interpretations diversified. Some people thought it was a river rushing downhill, others imagined the advance of a great army across a vast plain, others saw billowing nebulae in the darkness of space caught in the vortex of a black hole, but they all agreed that it was expressing some grand process, an evolutionary process. The movement was long, and an hour had passed before the theme at last began to change. The melody gradually split into two vying parts that smashed wildly into each other or tangled together.…

  “The classic style of Beethoven,” Clayderman declared, after a long stretch immersed in the grand music.

  The secretary general said, “It’s like a fleet smacking across huge waves on the sea.”

  “No,” said the US president, shaking his head. “Not that. You can tell that the two forces are not essentially different. I think it’s a battle that spans a world.”

  “Wait a moment,” interrupted the Japanese prime minister, breaking a long silence. “Do you really imagine you can comprehend alien art? Your understanding of the music may be no better than a cow’s appreciation for a lyre.”

  Clayderman said, “I think our understanding is basically correct. The common languages of the cosmos are mathematics and music.”

  The secretary general said, “Proving it won’t be difficult. Can we predict the theme or style of the next movement?”

  After a moment’s thought, the Chinese president said, “I’d say next will be an expression of worship, and the melody will possess a strict architectural beauty.”

  “You mean like Bach?”

  “Yes.”

  And so it was. The listeners seemed to hear a great imposing church and the echoes of their footsteps inside that magnificent space, and they were overcome by fear and awe of an all-encompassing power.

  Then the complicated melody turned simple again. The background music vanished, and a series of short, clear beats appeared in the infinite stillness: one, then two, then three, then four … and then one, four, nine, and sixteen … and then increasingly complex series.