Manifold: Space

by Stephen Baxter

  It had happened over and over. And it will happen again, she saw. Again and again, a drumbeat of extinction. That is what the Gaijin have learned.

  "And for us," Malenfant growled, "it's back to the fucking pond, every damn time... So much for Fermi's paradox. Nemoto was right. This is the equilibrium state for life and mind: a Galaxy full of new, young species struggling out from their home worlds, consumed by fear and hatred, burning their way across the nearby stars, stamping over the rubble of their forgotten predecessors."

  ...And this is what the Gaijin tried to show me, Madeleine recalled, on my first Saddle Point jaunt of all, to the burster neutron star: the star lichen, fast-evolving life-forms wiped out by a stellar fluke every fourteen seconds. It was a fractal image of this, the greater truth.

  The Galaxy image abruptly receded, the spiral arms and the core and the surrounding halo imploding on itself like a burst balloon. Madeleine gasped at the sudden illusory motion. The world congealed around her: grass and trees and that black sky, all of it illuminated by fierce blue cosmic light. She was flooded with intense physical relief, as if she could breathe again.

  But her mind was racing. "There must be ways to stop this. All we have to do is evade one collapse – and gain the time to put aside the wars and the trashing, and get a little smarter, and learn how to run the Galaxy properly. We don't have to put up with this shit."

  Malenfant smiled. "Nemoto always did call you a meddler."

  BUT YOU ARE RIGHT, the Gaijin said. SOME OF US ARE TRYING...

  Ahead of them, she saw a group of Neandertals. They were dancing, signing furiously to each other, jumping up and down in the light of the cosmos. Something was changing in the sky, and the Neandertals were responding.

  She looked that way. That cosmic light point seemed to be expanding.

  The unwrapping sky was full of stars. It was the center of the Galaxy.

  Malenfant was confronting the Gaijin. "Cassiopeia," he said softly, "what has all this got to do with me?"

  MALENFANT, the Gaijin said, YOU ARE OUR BEST HOPE.

  And now the Gaijin turned with a scrape of metal, a soft hiss as her feet sank deeper into the loam.

  IT IS RISING.

  She turned and began to stalk across the meadow, with that stiff, three-legged grace of hers, away from the stand of trees. Madeleine saw the Neandertals were following, a shadowy group of them, their muscles prominent in the starlight.

  Malenfant grabbed her hand.

  They walked through a meadow. The grass was damp, cool under her feet, and dew sparkled, a shattered mirror of the stars.

  They were all immersed in diffuse shadowless light, in this place where every corner of the sky glowed as bright as the surface of the Moon. The light was silvery, the colors bleached out of everything; the grass was a deep green, the leaves on the trees black. Madeleine wondered vaguely if there was enough nourishment in that Galaxy light to fuel photosynthesis, if life could survive on a rogue, sunless planet here, just eating the dense starlight.

  They topped a ridge and looked down over a broad, shallow valley. There were scattered trees and standing water, ribbons and pools of silver-blue, all of it still and a little eerie in the diffuse starlight.

  The Gaijin, Cassiopeia, had stopped, here at the crest. The Neandertals had gathered a little way away, along the ridge, and they were looking out over the valley.

  But now one of the Neandertals came shambling toward Malenfant, with that clumsy, inefficient gait of theirs. It was a man, stoop-shouldered, the flesh over his ribs soft and sagging, and sweat slicked over his shoulders. That great brow pulled his face forward, so that his chin almost rested on his chest.

  "Hello, Esau –" Malenfant said.

  Esau slapped him, and his fingers rattled, his fist thumping his forehead.

  Malenfant grinned, and translated. "Hello, Stupid." Malenfant seemed genuinely pleased to see this old Neandertal geezer again.

  But now Cassiopeia stirred, and Madeleine grabbed his arm. "Malenfant. Look. Oh, shit."

  A new star was rising above the valley, over the newly revealed horizon, brighter than the background wash.

  It was a neutron star, a brilliant crimson point. Near the star there were multiple lobes of light. They contained structure: veins and streamers, something like the wings of a butterfly around that ferocious, dwarfed body. They glowed pink and an eerie blue, perhaps through the synchrotron radiation of accelerated electrons.

  And there was something alongside the star. It looked like netting – scoop shaped, like a catcher's mitt, facing the star as if endeavoring to grasp it.

  Obviously artificial.

  Cassiopeia spoke. OUR JOURNEY IS NOT YET DONE, MALENFANT. WE MUST PENETRATE THE GALACTIC CENTER ITSELF. THIS IS WHAT WE WILL SEEK.

  "This is the site of a gamma-ray burster," Malenfant said. "A future reboot event. I'm right, aren't I, Cassiopeia?"

  THE STAR'S COMPANION IS AS YET SOME DISTANCE AWAY – BILLIONS OF KILOMETERS, IN FACT, TOO REMOTE TO SEE. AND YET THE CONVERGENCE HAS BEGUN. THE COLLISION IS INEVITABLE. UNLESS –

  "Unless somebody does something about it," Madeleine whispered.

  That strange artifact continued to ride higher in the sky, like a filmy, complex moon. It was a net, cast across the stars. It must have been thousands of kilometers wide.

  Madeleine found it impossible to believe it wasn't a few meters above her head, almost close enough for her to just reach out and touch. The human mind was just not programmed to see giant planet-spanning artifacts in the sky. Think of an aurora, she told herself, those curtains of light, rippling far above the air you breathe. And now imagine that: It would hang there far beyond any aurora, suspended in space, perhaps beyond the Moon...

  But there was something wrong: the netting was obviously unfinished, and great holes had been rent into its structure.

  "It's broken," Malenfant said.

  YOU WOULD CALL THIS A SHKADOV SAIL, the Gaijin said.

  It would be a thing of matter and energy, of lacy rigging and magnetic fields: a screen to reflect the neutron star's radiation and solar wind. But it was bound to the star by invisible ropes of gravity.

  "Ah," Madeleine said. "You disturb the symmetry of the solar wind. You see, Malenfant? The wind from the star will push at the sail. But the sail isn't going anywhere, relative to the star, because of gravity. So the wind gets turned back..."

  "It's a stellar rocket," Malenfant said. "Using the solar wind to push aside the star."

  THAT IS THE PURPOSE. WHEN COMPLETE IT WILL BE A DISC A HUNDRED THOUSAND KILOMETERS ACROSS, ALL OF IT LACED WITH INTELLIGENCE, A DYNAMIC THING, CAPABLE OF SHAPING THE STAR'S SOLAR WIND, RESPONDING TO ITS COMPLEX CURRENTS.

  Malenfant grinned. "Hot damn. Somebody is fighting back."

  "Who is building this thing? You?" Madeleine asked.

  NOT US ALONE. MANY RACES HAVE COME HERE, COOPERATED ON THE SAIL'S CONSTRUCTION. IT APPEARS TO HAVE BEEN A RELIC FROM A PREVIOUS CYCLE, FROM BEFORE A PREVIOUS REBOOT.

  "Like the Saddle Point network."

  Madeleine peered doubtfully at the huge, unlikely structure. "How can a sail like that move a neutron star – an object more massive than the Sun?"

  THE THRUST IS VERY SMALL, THE ACCELERATION MINUSCULE. BUT OVER LONG ENOUGH PERIODS, SMALL THRUSTS ARE SUFFICIENT TO MOVE WORLDS. EVEN STARS.

  "And will that be enough to stop the coalescence of this binary, to stop the reboot?" Madeleine asked.

  NOT TO STOP IT. TO POSTPONE IT GREATLY, BY ORDERS OF MAGNITUDE. IF WE CAN DELAY THIS STERILIZATION EVENT –

  "We might win time," Malenfant said.

  Madeleine challenged the Gaijin. "Is this really the best option? Haven't you come up with anything smarter?"

  Malenfant eyed her. "Like what?"

  "Hell, I don't know. You could use antigravity. Einstein's cosmological constant, the force that makes the universe expand. Or you could interfere with the fundamental constants of physics. For example there is a particle called the Higgs boson,
which gives matter its mass. If you took it away, switched it off, you could make your neutron stars lighter, and then just push them aside. In fact, take all the mass away and they would fly off at the speed of light. Easy. Give me a lever and I will move the world..."

  WE HAVE NO SUCH POWERS, Cassiopeia said, and Madeleine thought she detected sadness in that synthesized voice. WE HAVE SEARCHED. THERE IS NO CIVILIZATION SIGNIFICANTLY MORE ADVANCED THAN OUR OWN – EVEN BEYOND THE GALAXY.

  IT IS LIKE YOUR FERMI PARADOX. IF THEY EXISTED, WE WOULD SEE THEM. IMAGINE A GALAXY WITH ALL THE STARS FARMED, COVERED BY DYSON SPHERES, THEIR PHYSICS ALTERED PERHAPS TO EXTEND THEIR LIFETIMES. IMAGINE THE GALAXY ITSELF ENCLOSED BY A DYSON STRUCTURE. AND SO ON. EVEN SUCH CLUMSY ENGINEERING, ON SUCH A SCALE, WOULD BE VISIBLE. WE SEE NO SUCH THING, AS FAR OUT AS WE LOOK, AS DEEP INTO SPACE AND TIME.

  But it wasn't a surprise, Madeleine thought. How long would it take a galactic civilization to rise – even supposing somebody could survive the wars and assorted despoliation? Because of light speed, it would take a hundred thousand years for a message to cross the Galaxy just once. How many such exchanges would it take to homogenize the shared culture of a thousand species, born of different stars and biochemistries, creatures of flesh and metal, of rock and gas? A thousand Galaxy crossings, minimum?

  But that would take a hundred million years, and by that time the next burster would have blown its top, the next reboot driven everybody back to pond scum.

  So maybe this clumsy net really was the best anybody could do. But still, good intentions weren't enough.

  "Tens of millions of years," she said. "You'd have to maintain that damn thing for tens of millions of years, to make a difference. How can any species remotely like us, or even you, maintain a consistency of purpose across megayears? None of us even existed in anything like our present forms so long ago."

  BUT, Cassiopeia said slowly, WE MUST TRY.

  "We?" Malenfant said.

  YOU MUST JOIN US, MALENFANT.

  Madeleine clutched at Malenfant's hand. But he pushed her away. She looked up at him. His face was pinched, his eyes narrow. He was starting to feel scared, she realized, drawn out, as if pulled into space by the thing in the sky, up toward the zenith.

  Because, she realized, this is his destiny.

  Malenfant stood before the alien robot, silhouetted against Galaxy core light. He looked helplessly weak, Madeleine thought, a ragamuffin, before this representative of a cool, immeasurably ancient galactic power.

  Yet it was Cassiopeia who was supplicating before Malenfant, the human.

  "You can't do it," he said, wondering. "You can't complete this project. There is something... missing in you."

  THERE IS CONTROVERSY, Cassiopeia said.

  Madeleine glared up at that filmy structure. There were holes in the netting you could have passed a small planet through, places where thousand-kilometer threads seemed to have been burned or melted or distorted. Controversy.

  "Wars have been fought here," Malenfant said bluntly.

  THE RACES OF THE GALAXY ARE VERY DIVERGENT. UNITY DISSOLVES. THERE IS FREQUENT CONFLICT. SOMETIMES A RACE WILL SEEK TO TAKE THIS TECHNOLOGY AND USE IT FOR ITS OWN PURPOSES; THE OTHERS MUST MOUNT A COALITION TO STOP THE ROGUE. SOMETIMES A RACE WILL SIMPLY ATTEMPT TO IMPOSE ITS WILL ON OTHERS. THAT USUALLY ENDS IN CONFLICT, AND THE EXPULSION OR EXTERMINATION OF THE AMBITIOUS.

  Malenfant laughed. "Infighting. Sounds like every construction project I ever worked on."

  THERE ARE DIVERGENCES AMONG US.

  Madeleine looked up, startled. "You mean, even among the Gaijin?"

  THERE ARE FACTIONS WHO WOULD ARGUE THAT WE SHOULD ABANDON THE PROJECT TO OTHER RACES, CALCULATING –

  Malenfant grunted. "Calculating that the others will finish the job for you – without you incurring the costs of the work. Gambling on the altruism of others, while acting selfishly. Games theory."

  OTHERS SEEK A TIME SYMMETRY...

  Malenfant seemed baffled by that, but Madeleine thought she understood. "Like the Moon flowers, Malenfant. Do you know of them? If the Gaijin could train themselves to think backward in time, then they needn't face this... terminus... in the future."

  Malenfant laughed at the Gaijin, mocking.

  Madeleine felt disturbed at this blatant evidence of discord among the Gaijin. Weren't they supposed to merge into some kind of supermind, make decisions by consensus, with none of the crude arguing and splits of human beings? Dissension like this, so visible, must represent an agony of indecision in the Gaijin community, faced by the immense challenge of the star sail project. Indecision – or schizophrenia.

  Malenfant said, still challenging, "But your factions are wrong. Aren't they? Completing this project isn't a question of a game, theoretical or not. It is a question of sacrifice."

  Sacrifice? Madeleine wondered. Of what – or who?

  MALENFANT, YOU ARE SHORT-LIVED – YOUR LIVES SO BRIEF, IN FACT, THAT YOU CAN OBSERVE NONE OF THE UNIVERSE'S SIGNIFICANT PROCESSES. YOUR RESPONSE TO OUR PRESENCE IN THE SOLAR SYSTEM WAS SPLINTERED, CHAOTIC, FLUID. YOU DO NOT EVEN UNDERSTAND YOURSELVES.

  AND YET YOU TRANSCEND YOUR BREVITY. HUMANS, DOOMED TO BRIEF LIVES, CHOOSE DEATH VOLUNTARILY – FOR THE SAKE OF AN IDEA. AND WITH EVERY DEATH, THAT IDEA GROWS STRONGER.

  WE HAVE ENCOUNTERED MANY SPECIES ON OUR TRAVELS. RARELY HAVE WE ENCOUNTERED SUCH A CAPACITY FOR FAITH.

  Malenfant stalked back and forth on the hillside, obviously torn. "What are you talking about, Cassiopeia? Do you expect me to start a religion? You want me to teach faith to the toiling robots and cyborgs and whatnot who are building the neutron-star sail – something to unite them, to force them to bury their differences, to persist and complete the project across generations... Is that it?"

  No, Madeleine thought sadly. No, she is asking for something much more fundamental than that.

  She wants you, Malenfant. She wants your soul.

  And the Gaijin started talking of mind, and identity, and memes, and idea viruses.

  To Cassiopeia, Malenfant was scarcely sentient at all. From the Gaijin's point of view, Malenfant's mind was no more than a coalition of warring idea viruses: uneasy, illogically constructed, temporary. The ideas grouped together in complexes that reinforced each other, mutually aiding replication – just as those other replicators, genes, worked together through human bodies to promote their own reproduction.

  Yes, Madeleine thought, beginning to understand. And the most fundamental idea complex was the sense of self.

  A self was a collection of memories, beliefs, possession, hopes, fears, dreams: all of them ideas, or receptacles for ideas. If an idea accreted to the self – if it became Malenfant's idea, to be defended, if necessary, with his life – then its chance of replication was much stronger. His sense of self, of him self, was an illusion. Just a web woven by the manipulating idea viruses.

  The Gaijin had no such sense of self. But sometimes, that was what you needed.

  Malenfant understood. "Every damn one of the Gaijin has a memory that stretches back to those ugly yellow seas on the Cannonball. But they are... fluid. They break up into their component parts and scatter around and reassemble; or they merge in great ugly swarms and come out shuffled around. Identity for them is a transient thing, a pattern, like the shadow of a passing cloud. Not for us, though. And that's why the Gaijin don't have this." He stabbed a finger at his chest. "They don't have a sense of me."

  And without self, Madeleine saw, there could be no self-sacrifice.

  That was why the Gaijin couldn't handle the reboot prevention project. Only humans, it seemed – slaves of replicating ideas, nurtured and comforted by the illusion of the self – might be strong enough, crazy enough, for that.

  Through the dogged sense of his own character, Malenfant must give the fragmented beings toiling here a sense of purpose, of worth beyond their own sentience. A sense of sacrifice, of faith, of self. To help the Gaijin, to save the Galaxy, Malenfant was going to have to become like the Gaiji
n. He was going to have to lose himself – and, in the incomprehensible community that labored over the strands of the sail, find himself again.

  Malenfant, standing before the spidery Gaijin, was trembling. "And you think this will work?"

  No, Madeleine thought. But they are desperate. This is a throw of the dice. What else can they do?

  The Gaijin didn't reply.

  "I can't do this," Malenfant whispered at last, folding his hands over and over. "Don't ask me. Take it away from me."

  Madeleine longed to run to him, to embrace him, offer him simple human comfort, animal warmth. But she knew she must not.

  And still the Gaijin would not reply.

  Malenfant stalked off over the empty grassland, alone.

  Madeleine slept.

  When she woke, Malenfant was still gone.

  She lay on her back, peering up at a sky crowded with stars and glowing dust clouds. The stars seemed small, uniform, few of them bright and blue and young, as if they were deprived of fuel in this crammed space – as perhaps they were. And the dust clouds were disrupted, torn into ragged sheets and filaments by the immense forces that operated here.

  Toward the heart of the Galaxy itself, there was structure, Madeleine saw. Laced over a backdrop of star swarms she made out two loose rings of light, roughly concentric, from her point of view tipped to ellipticity. The rings were complex: She saw gas and dust, stars gathered into small, compact globular clusters, spherical knots of all-but-identical pinpoints. In one place the outer ring had erupted into a vast knot of star formation, tens of thousands of hot young blue stars blaring light from the ragged heart of a pink-white cloud. The rings were like expanding ripples, she saw, or billows of gas from some explosion. But if there had been an explosion it must have been immense indeed; that outermost ring was a coherent object a thousand light-years across, big enough to have contained almost all the naked-eye stars visible from Earth.

  And when Madeleine lifted her head, she saw that the inner ring was actually the base of an even larger formation that rose up and out of the general plane of the Galaxy. It was a ragged arch, traced out by filaments of shining gas, arching high into the less crowded sky above. It reminded her of images of solar flares, curving gusts of gas shaped by the Sun's magnetic field – but this, of course, was immeasurably vaster, an arch spanning hundreds of light-years. And rising out of the arch she glimpsed more immensity still, a vast jet of gas that thrust out of the Galaxy's plane, glimmering across thousands of light-years before dissipating into the dark.