Manifold: Space

by Stephen Baxter

  And there were more fundamental differences. Cassiopeia seemed much smarter at solving the equations than Malenfant, or any human. He managed to set out for her the equations of fluid mechanics, one of his specialties at college, and she seemed to understand them qualitatively: She could immediately see how these equations, which in themselves merely described how scraps of flowing water interacted with each other, implied phenomena like turbulence and laminar flow, implications it had taken humans years – using sophisticated mathematical and computational tools – to tease out.

  Could Cassiopeia look at the equations of relativity and see an implied universe of stars and planets and black holes? Could she look at the equations of quantum mechanics and see the intricate chemistry of living things?

  Of course, that increased smartness must lead to a qualitative jump in understanding. A chimp didn't think about things more simply than Malenfant did; it couldn't grasp some of his concepts at all. There were clearly areas where Cassiopeia was simply working above Malenfant's wretched head.

  Cassiopeia had spent time trying to teach him about a phenomenon just a little beyond his own horizon – as chaos theory might have been to an engineer of, say, the 1950s. It was something to do with the emergence of complexity. The Gaijin seemed able to see how complexity, even life, naturally emerged from the simplest of beginnings: not fundamental physical laws, but something even deeper than that – as far as he could make out, the essential mathematical logic that underlay all things. Human scientists had a glimmering of this. His own DNA somehow contained, in its few billion bases, enough information to generate a brain of three trillion connections...

  But for the Gaijin this principle went farther. It was like being given a table of prime numbers and being able to deduce atoms and stars and people as a necessary consequence of the existence of the primes. And since prime numbers, of course, existed everywhere, it followed there was life and people, humans and Gaijin, everywhere there could be.

  Life sprouting everywhere, like weeds in the cracks of a pavement. It was a remarkable, chilling thought.

  "Take me to your home," he'd said one day.

  Cassiopeia's choice of a human label for her remote home was "Zero-zero-zero-zero," the great sky map's origin of coordinates.

  I AM THE SUCCESSOR OF A REPLICANT CHAIN THAT EMERGED THERE, she'd said. She was descended from emigrants? Not exactly, because she'd continued. I RETAIN RECORDS OF ZERO-ZERO-ZERO-ZERO. Memories? Did each Gaijin come to awareness with copies of the memories of those who bore her – or constructed her? Were they, then, her memories, or a mere copy? IT IS POSSIBLE TO TRANSLATE TO ZERO-ZERO-ZERO-ZERO. THERE IS NO PURPOSE.

  "I'd like to see it."

  THERE ARE RECORDS THAT –

  "Your records only show me your world through your eyes. If we're ever going to understand each other, you have to let me see for myself."

  There was a long hesitation after that.

  FINALLY, she'd said then.

  "What?"

  THERE ARE MANY PLACES TO SEE. MANY WORLDS. BEFORE ZERO-ZERO-ZERO-ZERO.

  "I understand. One day..."

  ONE DAY.

  But not today, Malenfant thought, as he opened his eyes to the light of a foreign Sun. Not today. Today, we are both far from home.

  Cassiopeia provided him with an environment suit – a loosely cut coverall of what felt like a high-grade plastic. It had no zippers; he learned to seal it up by passing his thumb along the open seams. He lifted a hoodlike helmet over his head. There was a clear faceplate, a slightly opaque filter near his mouth.

  There was no independent air supply, just one layer of fabric. The whole thing jarred with Malenfant's intuition of the protection he would need to walk on an alien world. But Cassiopeia assured him it would be enough. And besides, the only alternative was his battered shuttle EMU suit, still with him, crammed into a corner of the lander, his only possession, long past its operational lifetime.

  "Open the door. Please."

  The lander door dilated away. The world beyond was green and black.

  The lander's cabin floor was almost flush with the ground, and he stepped out, pace by pace, testing his suit. Gravity was a little more than Earth normal, comfortingly familiar, and the air pressure just a little higher than Earth's sea level.

  First impressions:

  He was alone in an open forest, like park land. There were objects that were recognizably trees, about the size of Earth trees, and what appeared to be grass under his feet. Above his head a Sun sailed through a sky littered with high wispy cirrus clouds.

  He closed his eyes. He could hear the soft hiss of wind over the grass, and a distant piping, for all the world like a bird's song, and when he breathed in he filled his lungs with cool, crisp air.

  It might have been Earth.

  But when he opened his eyes, he saw a sky that was a lurid yellow-green. It was like a haze of industrial smog. The vegetation was a very deep green, almost black.

  And he could smell chlorine.

  His filter removed all but a trace of the chlorine compounds that polluted the atmosphere – including phosgene, toxic stuff humans had once used to slaughter each other. If not for his suit, this friendly looking world would soon kill him.

  Chlorine: That was the big difference here. Most of Earth's chlorine was locked up in the oceans, in the form of a stable chloride ion. This world seemed to have started out as roughly Earthlike. But something, one small detail, had been different: Here, something had pumped all that chlorine into the air.

  He walked forward, over grass that crushed softly under his feet.

  He reached a narrow valley, a rushing brook. There was a stand of trees nearby. The bed of the little stream was just a soft muddy clay, no sign of any rocks. The water was colorless, clear. He knelt down, stiffly, and dipped his fingers into the water. It was cold, its pressure gentle against his gloved hands.

  WARNING. SOLUTION OF HYDROGEN CHLORIDE. HYPOCHLORIC ACID.

  He snatched back his fingers. Like a swimming pool, he thought: Chlorine plus water gave a solution of acid and bleach. The weathering of any rocks here must be ferocious; no wonder only clays survived.

  He straightened up to inspect a tree. He touched branches, leaves, a trunk, even a blossom. But to his gloved fingers the leaves felt slippery, soapy.

  From a hollow in the tree trunk, at about his eye level, a small face peered out: the size and shape of a mouse's, perhaps, but with a central mouth, three eyes arranged symmetrically around it. The mouth opened, showing flat grinding surfaces, and the little creature hissed, emitting a cloud of greenish gas. Then it ducked back into the hole, out of his sight.

  The trunk didn't feel like wood. He reached up and broke off a twig; it snapped reluctantly. The interior was springy, fibrous. The leaves, the tree trunk, were made of some kind of natural plastic – perhaps a form of polyvinyl chloride, PVC. If he could smell the blossom, it would surely stink like toxic waste.

  It was like a grotesque model of a tree, a thing of plastic and industrial waste. And yet the breeze ruffled it convincingly, and sunlight dappled the green-black grass beneath.

  In his ear, Cassiopeia, from orbit, began to lecture him about biochemistry. THE LIVING THINGS HERE ARE CONSTRUCTED OF CELLS – ANALOGOUS TO LIVING THINGS ON EARTH, TO YOU. THEIR METABOLISMS ARE NOT TOLERANT OF THE CHLORINE. BUT THEY HAVE EVOLVED SHIELDING AT THE CELLULAR LEVEL...

  He interrupted. "There are trees here," he said. "Grass. Flowers. Animals." You see biochemistry. I see a flower, he thought.

  There was a long silence.

  It was the Gaijin way of seeing reality: from the equations of quantum mechanics, working up to a world. But that wasn't the way Malenfant thought. Humans, it seemed, were better at broad comprehension than the Gaijin, quicker at abstracting simplicity from complexity. This object before Malenfant wasn't a tree, because trees only grew on Earth. But it helped Malenfant to think in those terms, to seek patterns and map them back to what he knew.

&n
bsp; The Gaijin, slowly, were learning to ape his thinking.

  YES, came the reply. THERE ARE TREES.

  "Cassiopeia. Why did you bring me here, to this chlorine-drenched waste dump?"

  TO GATHER MORE DATA, MALENFANT.

  Malenfant scowled at the sky.

  The Gaijin seemed to be trying to educate him, for purposes of their own. They had shown him worlds, all of them very different, all of them bearing life. All of them scarred, in some way.

  The Gaijin saw the universe as some immense computer program, he was coming to believe: an algorithm for generating life and, presumably, mind wherever and whenever it could.

  The trouble was, the program had bugs.

  He grunted. "All right. Where? How?"

  WALK A KILOMETER, TOWARD THE SUN.

  Muttering complaints, sipping cool water from a pipe inside his hood to dispel the swimming-pool taste of chlorine, he stalked on.

  And, long before the kilometer was covered, he found people.

  There was a crowd of them, a hundred or more, gathered around what appeared to be a pit in the ground. They moved in a kind of dance, chains of people weaving in and out to a murmur of noise, soft as a wind blowing.

  Most of the dancers appeared to be somewhere near his own height. Few were taller, but several were a lot smaller – children? The elderly, withered by age?

  Not humans, of course. But people, yes.

  He glanced around, seeking cover. But Cassiopeia reassured him.

  THERE IS A PERCEPTUAL DYSFUNCTION, MALENFANT. He translated to himself: They can't see you.

  "Why not?... Oh. Captain Cook."

  COMMUNICATION DYSFUNCTION.

  There was a story – probably apocryphal – that on one of the islands visited by Cook, the natives had been unable even to see his great exploratory ships. They had never encountered such large floating artifacts before. It was only when Cook's crew put out in landing boats that the natives were able to comprehend.

  Thus, Malenfant was simply too strange an element in the dancers' world for them to perceive.

  "Never mind. Humans have limits like that too."

  Feeling a little bolder, he stepped forward, looking more closely.

  He picked out one of the dancers. She – he decided the sex arbitrarily – stood upright. She had a clearly defined torso and head, sets of upper and lower limbs. But she had three of everything – three arms, three legs – and her limbs articulated back and forth in a complex, graceful way he found unnerving. She didn't walk, exactly, shifting her weight from foot to stomping foot as he did. Rather, she spun around, whirling, letting one foot after another press lightly on the ground. It was high-speed and difficult to follow, like trying to figure out how a horse ran; but after he'd watched for a few seconds it seemed easy and natural.

  Her head, positioned up at the top of her trunk, was about where his was. He saw three eyes, what appeared to be a mouth, other orifices that might be ears, nostrils. She seemed to be naked save for a belt slung over one of her three shoulders, like a sash. He could see tools dangling there: a lump of quartzlike rock that could have been a handheld hammer, what looked like a bow of the natural-plastic wood. Stone Age technology, he thought.

  ...Of course Stone Age. Most metals would just corrode here. Gold would survive, but try making a workable ax out of that. Even fire would be problematic; all that chlorine would inhibit flame. There could be no ceramics, for instance.

  Because of an accident of biochemistry these people were stuck forever in the Stone Age. And since most rock would be corroded away, there wasn't even much of that.

  Maybe these people had a rich culture, an oral tradition, dance. But that was all they could ever have. He watched the woman-thing whirl, with admiration, with pity.

  WHAT IS THE PURPOSE OF THE PATTERNLESS SOUNDS THEY MAKE?

  "Patternless..." Malenfant smiled. "Perceptual incongruence, Cassiopeia. Transform your data. Look at the frequency content, the ratios between the tones... We've discussed this before." The Gaijin analyzed sound digitally, not with analog microphonelike systems like the human ear. And so the patterns they judged as agreeable – valuable, anyhow – were complex numeric constructs, not the harmonies that pleased human ears.

  A long silence. IT IS A FORM OF MUSIC, Cassiopeia stated.

  "Yes. They're singing, Cassiopeia. Singing, that's all."

  Now the dancing reached a climax, the howl of voices more intense. One of the dancers spun out of the group, whirling in a decaying orbit toward that pit around which they all gyrated.

  Then, with a fast shimmying movement, she got to her belly and slid gracefully into the hole.

  The dancers continued, for thirty seconds, a minute, two, three, four. Malenfant just watched.

  At last the potholer returned. Malenfant saw that trio of upper arms come flopping over the rim of the pit. She seemed to be in trouble. Dancers broke away, four or five of them hurrying to haul their partner out of the hole.

  She lay on her back, shuddering, obviously distressed. But she held up something to the light. It was long, dark brown, pitted, and heavily corroded. It was a bone – bigger than any human bone, half Malenfant's height, and with a strange protrusion at one end – but unmistakably a bone even so.

  "Cassiopeia – what's hurting her?"

  CHLORINE POISONING. CHLORINE IS A HEAVY GAS. IT POOLS IN LOW PLACES.

  "Like that hole in the ground."

  YES.

  "And so, when she went down there to retrieve that bone..."

  The dancer had been asphyxiated. She was tolerant of chlorine, but couldn't breathe it.

  The potholer passed the bone on to another. Malenfant saw that where her long, flipperlike hand had wrapped around the bone, it had been corroded. And when the dancer took hold of it, the bone surface sizzled and smoked to her touch. Carbonate, burning in the air.

  That's what would happen to my bones here, slowly but surely. That bone can't have belonged to any creature now extant, here on this chlorine-drenched planet.

  SHE SACRIFICED HER LIFE, Cassiopeia said.

  "Why? What's the point?"

  Cassiopeia seemed to hesitate. WE WERE HOPING YOU COULD TELL US.

  He turned his back on the whirling, singing dancers and trudged back to his lander.

  He felt exhausted, depressed.

  "This wasn't always a chlorine dump. Was it, Cassiopeia?"

  NO, she replied.

  That bone pit was the key. That, and the sparse biosphere.

  Once this had been a world very much like Earth, with the chlorine locked in the ocean. Then it had been... seeded. All it had taken was a single strain of chlorine-fixing microbes. The bugs found themselves in a friendly, bland atmosphere, with lots of chloride just floating around in the ocean, waiting to be used. And so it began.

  It had happened a long time ago, a hundred million years or more. Time enough for life-forms to adapt. Some of them had evolved defenses against the spreading stain of chlorine. Others had learned to incorporate chlorine into their cells to make themselves unpalatable to anyone wanting to eat them. Some even used the chlorine as a gas attack against predators or prey, like the tree mouse that had spat in his face. And so on. Thus, a chlorine-resistant biosphere had arisen.

  But the bone pit contained relics of the original native life, sent to extinction by the chlorine. The relics must have been trapped for megayears under a layer of limestone; but at last the limestone just dissolved, under rain like battery acid, exposing the bones.

  The Gaijin believed the seeding of the planet with chlorine fixers had probably been deliberate.

  WE HAVE FOUND MANY WAYS

  TO KILL A WORLD, MALENFANT. THIS IS ONE OF THE MORE SUBTLE.

  Subtle and disguised; the chlorine fixers might have evolved naturally, and after such a length of time it would be hard to prove otherwise. But the Gaijin had come across this modus operandi before.

  The thought shocked him more deeply than he had thought possible. This world wa
sn't natural; it was like a corpse, strangled.

  WE UNDERSTAND HOW TO KILL A WORLD, Cassiopeia said. WE EVEN UNDERSTAND WHY.

  "Competition for resources?"

  BUT WE DON'T UNDERSTAND WHY THAT DANCER KILLED HERSELF.

  "It was ritual, Cassiopeia. As far as I could see. Religion, maybe." The dancers couldn't possibly understand the story of their world, the meaning of the ancient fossils. Maybe they thought they were the bones of the giants who had created their world.

  But this was the most alien thing of all to the Gaijin.

  MALENFANT, WHAT IS IT THAT MAKES A SENTIENT BEING SACRIFICE THE POSSIBILITY OF A TRILLION YEARS OF CONSCIOUSNESS FOR AN IDEA?

  "Hell, I can't tell you that."

  BUT YOU DID THE SAME WHEN YOU CAME THROUGH THE SOL GATEWAY. YOU COULD NOT KNOW WHAT LAY ON THE OTHER SIDE. YOU MUST HAVE EXPECTED TO DIE.

  "What is this, Anthropology 101? Is this so important to you?"

  The answer startled him.

  MALENFANT, IT MAY BE THE MOST IMPORTANT THING OF ALL.

  The planet was folding over, dwindling into a watery blue dot, achingly familiar. But it was the scene of a huge crime, a biocide on a scale he could barely comprehend – and one committed so impossibly long ago.

  "So strange," he murmured. "Earth, the Solar System, contains nothing like this."

  The Gaijin would not reply to that, and he felt a deep, abiding unease.

  But the Solar System was primordial. You could see that was true.

  Wasn't it?

  Chapter 11

  Anomalies

  Carole Lerner drifted out of the air lock.

  She was tethered by a series of metal clips to a guideline, along which she pulled herself hand over hand. The line connected her ship to a moonlet. The line seemed flimsy and fragile, strung as it was between spaceship and moonlet, two objects that floated, resting on no support, in empty three-dimensional space.