Hold Up The Sky

by Liu Cixin

  Bai Bing took out two cigarettes, handing one to Song Cheng. He lit his own and drew deeply, blowing the smoke at the three dead faces on the screen. “I’m definitely destroying the digital mirror. I only kept it around until now so you can see. But nothing we do now matters. That’s one bit of consolation: everything that happens afterward has nothing to do with us.”

  “Someone else created a digital mirror too?”

  “The theory and technology for it are both out there, and according to superstring theory, the number of viable initialization parameter sets is enormous, but still finite. If you keep going down the list, you’ll eventually run into that one set…. More than thirty thousand years from now, till the last days of civilization, humanity will still be thanking and worshiping a guy named Nick Kristoff.”

  “Who is he?”

  “According to the historical records: a devout Christian, physicist, and inventor of the digital mirror software.”

  MIRROR ERA

  FIVE MONTHS LATER, AT THE PRINCETON UNIVERSITY

  CENTER OF EXPERIMENTAL COSMOLOGY

  When the radiant sea of stars appeared on one of the fifty display screens, all of the scientists and engineers present erupted into cheers. Five superstring computers stood here, each simulating ten virtual machines, for a total of fifty sets of big bang simulations running day and night. This newly created virtual universe was the 32,961st.

  Only one middle-aged man remained unmoved. He was heavy-browed and alert-eyed, imposing in appearance, the silver cross at his breast all the more striking against his black sweater. He made the sign of the cross, and asked:

  “Gravitational constant?”

  “6.67 times 10–11!”

  “Speed of light in a vacuum?”

  “2.998 times 105 kilometers per second!”

  “Planck’s constant?”

  “6.626 times 10–34!”

  “Charge of electron?”

  “1.602 times 10–19 coulombs!”

  “One plus one?” He gravely kissed the cross at his chest.

  “Equals two! This is our universe, Professor Kristoff!”

  ODE TO JOY

  An alternate history of the sophon

  TRANSLATED BY JOEL MARTINSEN

  THE CONCERT

  The concert held to close the final session of the United Nations was a depressing one.

  A utilitarian attitude toward the body, dating back to bad precedents set at the start of the century, had been on the rise; countries assumed the UN was a tool to achieve their interests, and interpreted its charter to their own benefit. Smaller nations challenged the authority of the permanent members, while each permanent member believed it deserved more authority within the organization, which lost all authority of its own as a result. A decade on, all efforts at a rescue had failed, and everyone agreed that the UN and the idealism it represented no longer applied to the real world. It was time to be rid of it.

  All heads of state assembled for the final session, to observe a solemn funeral for the UN. The concert, held on the lawn outside the General Assembly building, was the final item on the program.

  It was well after sunset. This was the most bewitching time of day, the handover from day to night when the cares of reality were masked by the growing dusk. The world was still visible under the last light from the setting sun, and on the lawn, the air was thick with the scent of budding flowers.

  The secretary general was the last to arrive. On the lawn, she ran across Richard Clayderman,1 one of the evening’s featured performers, and struck up a cheerful conversation.

  “Your playing fascinates me,” she told the prince of pianists with a smile.

  Clayderman, dressed in his favorite snow-white suit, looked uncomfortable. “If that’s genuine, then I’m overjoyed. But I’ve heard there have been complaints about my appearance at a concert like this.”

  Not merely complaints. The head of UNESCO, a noted art theorist, had publicly criticized Clayderman’s playing as “busker-level,” and his performances as “blasphemy against piano artistry.”

  The secretary general lifted a hand to stop him. “The UN can have none of classical music’s arrogance. You’ve erected a bridge from classical music to the masses, and so must we bring humanity’s highest ideals directly to the common people. That’s why you were invited here tonight. Believe me, when I first heard your music under the sweltering sun in Africa, I had the feeling of standing in a ditch looking up at the stars. It was intoxicating.”

  Clayderman gestured toward the leaders on the lawn. “It feels more like a family gathering than a UN event.”

  The secretary general looked over the crowd. “On this lawn, for tonight at least, we have realized a utopia.”

  She crossed the lawn and reached the front row. It was a glorious evening. She had planned on switching off her political sixth sense and just relaxing for once, taking her place as an ordinary member of the audience, but this proved impossible. That sense had picked up a situation: The president of China, engaged in conversation with the president of the United States, looked up at the sky for a moment. The act itself was utterly unremarkable, but the secretary general noticed that it was a little on the long side, perhaps just an extra second or two, but she’d noticed it. When the secretary general sat down after shaking hands with the other world leaders in the front row, the Chinese president looked up at the sky again, confirming his perception. Where national leaders are concerned, apparently random actions are in fact highly precise, and under normal circumstances, this act would not have been repeated. The US president also noticed it.

  “The lights of New York wash out the stars. The sky’s far brighter than this over DC,” he said.

  The Chinese president nodded but said nothing.

  The US president went on, “I like looking at the stars, too. In the ever-changing course of history, our profession needs an immovable reference object.”

  “That object is an illusion,” the Chinese president said.

  “Why do you say that?”

  Instead of responding directly, the Chinese president pointed at a cluster of stars that had just come out. “Look, that’s the Southern Cross, and that’s Canis Major.”

  The US president smiled. “You’ve proven they’re immovable enough. Ten thousand years ago, primitive man would have seen the same Southern Cross and Canis Major as we do today. They may have even come up with those names.”

  “No, Mr. President. In fact, the sky might even have been different just yesterday.” The Chinese president looked up for a third time. He remained calm, but the steel in his eyes made the other two nervous. They looked at the same placid sky they had seen so many times before; nothing seemed wrong. They looked questioningly at the Chinese president.

  “The two constellations I just noted should only be visible from the southern hemisphere,” he said without pointing them out or looking upward. He turned thoughtfully toward the horizon.

  The secretary general and US president looked questioningly at him.

  “We’re looking at the sky from the other side of the Earth,” he said.

  The US president yelped, but then restrained himself and said in a voice even lower than before, “You’ve got to be kidding.”

  “Look, what’s that?” the secretary general said, pointing at the sky with a hand raised only to eye level so as not to alarm the others.

  “The moon, of course,” the US president said after a brief glance overhead. But when the Chinese president slowly shook his head, he looked up a second time and was less certain. At first, the semicircular shape in the sky looked like the moon in first quarter, but it was bluish, as if a scrap of daytime sky had gotten stuck. The US president looked more closely at the blue semicircle. He held out a finger and measured the blue moon against it. “It’s growing.”

  The three politicians stared up at the sky, not caring anymore if they’d startle the others. The heads of state in the surrounding seats noticed their movements, and more p
eople looked upward. The orchestra on the outdoor stage abruptly stopped its warm-up.

  By now, it was clear that the blue semicircle was not the moon, because its diameter had grown to twice that, and its darkness-shrouded other half was now visible in dim blue. In its brighter half, details could be made out; its surface was not a uniform blue but had patches of brown.

  “God! Isn’t that North America?” someone shouted. They were right. You could distinguish the familiar shape of the continent, which lay smack on the border between the light and dark halves. (It may have occurred to someone that was the very same position they occupied.) Then they found Asia, and the Arctic Ocean and the Bering Strait….

  “It’s … Earth!”

  The US president drew back his finger. The blue sphere in the sky was now growing at a rate visible without a reference object, and was now at least three times the diameter of the moon. At first, it looked like a balloon rapidly inflating in the sky, but then a shout from the crowd abruptly changed that impression:

  “It’s falling!”

  The shout provided a reasonable interpretation of the scene before them. Regardless of its accuracy, they immediately had a new sense of what was happening: another Earth was crashing toward them in space! The approaching blue planet now occupied a third of the sky, and surface details could be made out: brown continents covered in mountain wrinkles, cloud coverage looking like unmelted snow, outlined in black from the shadows cast on the ground. There was white at the North Pole, parts of which glittered—ice, rather than clouds. On a blue ocean, a snow-white object spiraled lazily with the delicate beauty of a velvet flower in a blue crystal vase—a newborn hurricane…. But when the huge blue sphere grew to cover half the sky, their perception experienced an almost simultaneous transformation.

  “God! We’re falling!”

  The feeling of inversion came in an instant. The sphere filling half the sky gave them a feeling of height, or that the ground beneath their feet had vanished and they were now falling toward the other Earth. Its surface was clearer now, and on the dark side, not far from the shadow line, those with keen eyes could see a faint glowing band: the lights of America’s East Coast cities, their own location in New York a somewhat brighter spot within it. The other planet now filled two-thirds of the sky, and it seemed as if the two Earths would collide. There were screams from the crowd, and many of them shut their eyes.

  Then all was still. The Earth overhead was no longer falling (or the ground they stood on was no longer falling toward it). The sphere hung motionless covering two-thirds of the sky, bathing the land in its blue glow.

  Now sounds of chaos could be heard from the city, but the occupants of the lawn had the strongest nerves on the planet in unstable situations, so they held back their panic at the nightmarish scene and approached it more quietly.

  “It’s a hallucination,” the secretary general said.

  “Yes,” the Chinese president said. “If it were real, we’d feel the gravity. And this close to the sea, we’d be drowned by the tide.”

  “It’s more than just the tides,” the Russian president said. “The two Earths would be torn to pieces by their mutual attraction.”

  “The laws of physics don’t permit two Earths to remain motionless,” the Japanese prime minister said, and, turning to the Chinese president, added, “When that Earth first appeared, you were saying that the stars of the southern hemisphere were in the sky above us. Could the two phenomena be connected?” It was a tacit admission of eavesdropping, but they were past caring at this point.

  “Perhaps we’re about to find out,” the US president said. He spoke into a mobile phone; the secretary of state, at his elbow, informed the others that he was speaking with the International Space Station. And so they focused their anticipation on the president, who listened attentively to the phone but said only a few words. Silence reigned on the lawn, where in the blue light of that other Earth they looked like a throng of ghosts. After about two minutes, the president set down the phone, climbed onto a chair, and shouted to the expectant crowd:

  “It’s simple. A huge mirror has appeared next to the Earth!”

  THE MIRROR

  There was no way to describe it other than a huge mirror. Its surface perfectly reflected visual light as well as radar with no energy or image loss. Viewed from the right distance, the Earth would look like a stone on a go board ten billion square kilometers in area.

  It shouldn’t have been difficult for Endeavor’s astronauts to obtain preliminary data, since an astronomer and a space physicist were on board and had all the necessary equipment available and at their disposal, including the ISS, to conduct observations; however, their momentary panic had nearly sent the orbiter to its doom. The ISS was a fully-equipped observation platform, but its orbit was not conducive to observing an object situated 450 kilometers above the North Pole nearly perpendicular to the Earth’s axis. Endeavor’s orbit sent it over the poles so it could carry out observations of the ozone holes; at a height of 280 kilometers, it was flying right between the Earth and the mirror.

  Flying with an Earth on either side was nightmarish, like speeding along a canyon with blue cliffs towering above them. The pilot insisted it was a mirage, like the spatial disorientation he had experienced twice during his three thousand hours in a fighter jet, but the commander was convinced there really were two Earths. He ordered their orbit adjusted to compensate for the gravitational pull of the second one, but the astronomer stopped him in time. Once they got over their initial shock and learned from observations of the shuttle’s orbit that one of the two Earths had no mass, they let out a sigh of relief: if they had made the compensational adjustments, Endeavor would be nothing more than a shooting star over the North Pole.

  The astronauts carefully observed the massless Earth. Visual inspection indicated the orbiter was much farther away from it, but its North Pole seemed little different from that of the nearer Earth, if not entirely identical. They saw laser beams emitting from both North Poles, two long, dark red snakes twisting slowly in identical shapes at identical positions. Eventually they discovered one thing that the nearer Earth did not have: an object in flight above the massless Earth. Visually they judged it to be in an orbit roughly three hundred kilometers above its surface, but when they attempted to probe its orbit more precisely using shipboard radar, the radar seemed to bounce back from a solid wall a hundred-odd kilometers away. The massless Earth and the flying object were on the opposite side of that wall. Observing the object through the cockpit window using high-powered binoculars, the commander saw another space shuttle flying in low orbit over the frozen Arctic ice pack like a moth crawling along a blue striped wall. There was a figure behind that shuttle’s cockpit window, looking through binoculars. The commander waved, and the figure waved at the same time.

  And so they discovered the mirror.

  They altered course to draw closer to the mirror. At a distance of three kilometers, the astronauts could see clearly Endeavor’s reflection six kilometers away, the glow of its aft engines lending it the form of a creeping firefly.

  One astronaut took a spacewalk for humanity’s first close encounter with the mirror. Thrusters on the suit spurted streams of white, speeding him across the distance. Carefully, he adjusted the jets to bring himself into position ten meters from the mirror. His reflection was remarkably clear, without any distortion. Since he was in orbit but the mirror was stationary with respect to the Earth, he had a relative speed of ten kilometers per second. He was racing past it, but no motion at all was visible. It was the smoothest, shiniest surface in the universe.

  When the astronaut decelerated, his thruster jets had been aimed at the mirror for an extended period, and a white fog of benzene propellant had drifted toward it. During previous space walks, whenever the fog had come into contact with the shuttle or the outside wall of the ISS, it would leave a conspicuous smudge; he imagined it would be the same with the mirror, except that with the high relative velo
city, the smudge would be a long stripe, like he used to draw with soap on the bathroom mirror as a child. But he saw nothing. The fog vanished upon contact with the mirror, whose surface remained bright as ever.

  The shuttle’s orbital trajectory gave them only a limited amount of time near the mirror, prompting the astronaut to act quickly. In an almost unconscious act the moment the fog disappeared, he took a wrench out of his tool bag and tossed it at the mirror, but once it left his hand, he and the astronauts aboard the shuttle were paralyzed with the realization that the relative velocity between it and the mirror gave it the force of a bomb. In terror they watched the wrench tumble toward the mirror and had a vision of the spiderweb fractures that in just moments would spread like lightning across the surface from the point of impact, and then the enormous mirror shattering into billions of glittering fragments, a sea of silver in the blackness of space…. But when the wrench touched the surface it vanished without a trace, and the mirror remained as smooth as before.

  It actually wasn’t hard to see that the mirror was massless, not a physical body, since floating motionless over Earth’s North Pole would be impossible otherwise. (It might be more accurate to state, given their relative sizes, that the Earth was floating in the middle of the mirror.) Rather than a physical entity, the mirror was a field of some sort. Contact with the fog and the wrench proved that.

  Delicately manipulating his thrusters and making continual microadjustments of the jets, the astronaut drew within half a meter of the mirror. He stared straight into his reflection, amazed once again at its fidelity: a perfect copy, one perhaps even more finely wrought than the original. He extended a hand toward it until he and his reflected hand were practically touching, separated by less than a centimeter. His earpiece was silent—the commander did not order him to stop—so he pushed forward, and his hand disappeared into the mirror. He and his image were joined at the wrist. There had been no sensation of contact. He retracted his hand and looked at it carefully. The suit glove was perfectly unharmed. No marks whatsoever.