Permutation City

by Greg Egan

  When they were gone, he sat and waited. The grass was soft, the sky was bright, the air was calm. He wasn’t fooled. There’d been moments like this before: moments approaching tranquility. They meant nothing, heralded nothing, changed nothing. There’d always be another vision of decay, another nightmare of mutilation. And another return to Hamburg.

  He scratched the smooth skin of his abdomen; the last number he’d cut had healed long ago. Since then, he’d stabbed his body in a thousand places; slit his wrists and throat, punctured his lungs, sliced open the femoral artery. Or so he believed; no evidence of the injuries remained.

  The stillness of the garden began to unnerve him. There was a blankness to the scene he couldn’t penetrate, as if he was staring at an incomprehensible diagram, or an abstract painting he couldn’t quite parse. As he gazed across the lawn, the colors and textures flooding in on him suddenly dissociated completely into meaningless patches of light. Nothing had moved, nothing had changed – but his power to interpret the arrangement of shades and hues had vanished; the garden had ceased to exist.

  Panicking, Thomas reached blindly for the scar on his forearm. When his fingers made contact, the effect was immediate: the world around him came together again. He sat, rigid for a moment, waiting to see what would happen next, but the stretch of dark green in the corner of his eye remained a shadow cast by a fountain, the blue expanse above remained the sky.

  He curled up on the grass, stroking the dead skin, crooning to himself. He believed he’d once hacked the scar right off; the new wound he’d made had healed without a trace – but the original faint white line had reappeared in its proper place. It was the sole mark of his identity, now. His face, when he sought it in the mirrors inside the house, was unrecognizable. His name was a meaningless jumble of sounds. But whenever he began to lose his sense of himself, he only had to touch the scar to recall everything which defined him.

  He closed his eyes.

  He danced around the flat with Anna. She stank of alcohol, sweat and perfume. He was ready to ask her to marry him; he could feel the moment approaching, and he was almost suffocating with fear, and hope.

  He said, “God, you’re beautiful.”

  Order my life. I’m nothing without you: fragments of time, fragments of words, fragments of feelings. Make sense of me. Make me whole.

  Anna said, “I’m going to ask you for something I’ve never asked for before. I’ve been trying to work up the courage all day.”

  “You can ask for anything.”

  Let me understand you. Let me piece you together, hold you together. Let me help you to explain yourself.

  She said, “I have a friend, with a lot of cash. Almost two hundred thousand marks. He needs someone who can—”

  Thomas stepped back from her, then struck her hard across the face. He felt betrayed; wounded and ridiculous. She started punching him in the chest and face; he stood there and let her do it for a while, then grabbed both her hands by the wrists.

  She caught her breath. “Let go of me.”

  “I’m sorry.”

  “Then let go of me.”

  He didn’t. He said, “I’m not a money laundering facility for your friends.”

  She looked at him pityingly. “Oh, what have I done? Offended your high moral principles? All I did was ask. You might have made yourself useful. Never mind. I should have known it was too much to expect.”

  He pushed his face close to hers. “Where are you going to be, in ten years’ time? In prison? At the bottom of the Elbe?”

  “Fuck off.”

  “Where? Tell me?”

  She said, “I can think of worse fates. I could end up playing happy families with a middle-aged banker.”

  Thomas threw her toward the wall. Her feet slipped from under her before she hit it; her head struck the bricks as she was going down.

  He crouched beside her, disbelieving. There was a wide gash in the back of her head. She was breathing. He patted her cheeks, then tried to open her eyes; they’d rolled up into her skull. She’d ended up almost sitting on the floor, legs sprawled in front of her, head lolling against the wall. Blood pooled around her.

  He said, “Think fast. Think fast.”

  Time slowed. Every detail in the room clamored for attention. The light from the one dull bulb in the ceiling was almost blinding; every edge of every shadow was razor sharp. Thomas shifted on the lawn, felt the grass brush against him. It would take so little strength, so little courage, so little love. It was not beyond imagining—

  Anna’s face burned his eyes, sweet and terrible. He had never been so afraid. He knew that if he failed to kill her, he was nothing; no other part of him remained. Only her death made sense of what he’d become, the shame and madness which were all he had left. To believe that he had saved her life would be to forget himself forever.

  To die.

  He forced himself to lie still on the grass; waves of numbness swept through his body.

  Shaking, he phoned for an ambulance. His voice surprised him; he sounded calm, in control. Then he knelt beside Anna, and slid one hand behind her head. Warm blood trickled down his arm, under the sleeve of his shirt. If she lived, he might not go to prison – but the scandal would still destroy him. He cursed himself, and put his ear to her mouth. She hadn’t stopped breathing. His father would disinherit him. He stared blankly into the future, and stroked Anna’s cheek.

  He heard the paramedics on the stairs. The door was locked; he had to get up to let them in. He stood back helplessly as they examined her, then lifted her onto the stretcher. He followed them out through the front door. One of the men locked eyes with him coldly as they maneuvered the stretcher around the landing. “Pay extra to smack them around, do you?”

  Thomas shook his head innocently. “It’s not what it looks like.”

  Reluctantly, they let him ride in the back. Thomas heard the driver radio the police. He held Anna’s hand and gazed down at her. Her fingers were icy, her face was white. The ambulance took a corner; he reached out with his free hand to steady himself. Without looking up, he asked, “Will she be all right?”

  “Nobody will know that until she’s been X-rayed.”

  “It was an accident. We were dancing. She slipped.”

  “Whatever you say.”

  They sped through the streets, weaving through a universe of neon and headlights rendered silent by the wail of the siren. Thomas kept his eyes on Anna. He held her hand tightly, and with all of his being willed her to live, but he resisted the urge to pray.

  Chapter 30

  The leaders of the Contact Group assembled in Maria’s apartment. They’d barely taken their seats when Durham said, “I think we should move to my territory before we proceed any further. I’m on the far side of the hub from the Autoverse region – for what that’s worth. If distance still means anything, we should at least try to run our models somewhere reliable.”

  Maria felt sick. The City itself was right beside the Autoverse: the fairground on the edge of the desert. But no Elysians were being computed in that public space; only buildings and puppet pedestrians. She said, “Six other founders have pyramids adjoining the Autoverse. If you think there’s a chance that effects are spilling over the border … can’t you find a pretext to get them to move their people as far away as possible? You don’t have to spell things out – you don’t have to tell them anything that might increase the danger.”

  Durham said wearily, “I’ve had enough trouble persuading thirty-seven dedicated Autoverse scholars to occupy themselves with projects which will keep them out of our way. If I started suggesting to Elaine Sanderson, Angelo Repetto and Tetsuo Tsukamoto that they rearrange the geometry of their computing resources, it would take them about ten seconds to put the entire Autoverse under scrutiny, to try to find out what’s going on. And the other three pyramids are occupied by hermits who haven’t shown themselves since the launch; we couldn’t warn them even if we wanted to. The best thing we can do is deal wit
h the problem as quickly – and inconspicuously – as possible.”

  Maria glanced at Dominic Repetto, but apparently he was resigned to the need to keep his family in the dark. She said, “It makes me feel like a coward. Fleeing to the opposite side of the universe, while we poke the hornet’s nest by remote control.”

  Repetto said dryly, “Don’t worry; for all we know, the TVC geometry might be irrelevant. The logical connection between us and the Autoverse might put as at more risk than the closest physical neighbors.”

  Maria still chose to do everything manually, via her “solid” terminal; no interface windows floating in midair, no telepathic links to her exoself. Zemansky showed her how to run the obscure utility program which would transport her right out of her own territory. The less wealthy Copies back on Earth had darted from continent to continent in search of the cheapest QIPS – but in Elysium there would never have been a reason for anyone to shift this way, before. As she okayed the last query on the terminal, she pictured her model being halted, taken apart, and piped through the hub into Durham’s pyramid – no doubt with a billion careful verification steps along the way … but it was impossible to know what even the most stringent error-checking procedures were worth, now that the deepest rules upon which they relied had been called into question.

  As a final touch, Durham cloned the apartment, and they moved – imperceptibly – to the duplicated version. Maria glanced out the window. “Did you copy the whole City as well?”

  “No. That’s the original you’re looking at; I’ve patched-in a genuine view.”

  Zemansky created a series of interface windows on the living room wall; one showed the region running the Autoverse, with the triangular face which bordered Maria’s own pyramid seen head-on. On top of the software map – the midnight-blue of the Autoverse cellular automaton program, finely veined with silver spy software – she overlaid a schematic of the Lambertian planetary system, the orbits weirdly chopped up and rearranged to fit into the five adjacent pyramids. The space being modeled was – on its own terms – a relatively thin disk, only a few hundred thousand kilometers thick, but stretching about fifty per cent beyond the orbit of the outermost planet. Most of it was empty – or filled with nothing but light streaming out from the sun – but there were no shortcuts taken; every cubic kilometer, however featureless, was being modeled right down to the level of Autoverse cells. The profligacy of it was breathtaking; Maria could barely look at the map without trying to think of techniques to approximate the computations going on in all that near-vacuum. When she forced herself to stop and accept the thing as it was, she realized that she’d never fully grasped the scale of Elysium before. She’d toured the Lambertian biosphere from the planetary level right down to the molecular – but that was nothing compared to a solar-system’s-worth of subatomic calculations.

  Durham touched her elbow. “I’m going to need your authorization.” She went with him to the terminal he’d created for himself in a corner of the room, and typed out the code number which had been embedded in her scan file back on Earth; the ninety-nine digits flowed from her fingers effortlessly, as if she’d rehearsed the sequence a thousand times. The code which would have granted her access to her deceased estate, on Earth, here unlocked the processors of her pyramid.

  She said, “I really am your accomplice, now. Who goes to prison when you commit a crime using my ID?”

  “We don’t have prisons.”

  “So what exactly will the other Elysians do to us, when they find out what we’ve done?”

  “Express appropriate gratitude.”

  Zemansky zoomed in on the map to show the individual TVC processors along the border, and then enlarged the view still further to reveal their elaborate structure. It looked like a false-color schematic of an array of three-dimensional microcircuits – but it was too rectilinear, too perfect, to be a micrograph of any real object. The map was largely conjecture, now: a simulation guided by limited data flowing in from the grid itself. There were good reasons why it “should have been” correct, but there could be no watertight evidence that anything they were seeing was actually there.

  Zemansky manipulated the view until they were peering straight down the middle of the thin layer of transparent “null” cells which separated the Autoverse region from Maria’s territory – bringing her own processors into sight for the first time. An arrow in a small key diagram above showed the orientation; they were looking straight toward the distant hub. All the processors were structurally identical, but those in the Autoverse were alive with the coded streams of activated states marking data flows, while her own were almost idle. Then Durham plugged her territory into the software he was running, and a wave of data swept out from the hub – looking like something from the stargate sequence in 2001 – as the processors were reprogrammed. The real wave would have passed in a Standard Time picosecond; the map was smart enough to show the event in slow motion.

  The reprogrammed processors flickered with data – and then began to sprout construction wires. Every processor in the TVC grid was a von Neumann machine as well as a Turing machine – a universal constructor as well as a universal computer. The only construction task they’d performed in the past had been a one-off act of self-replication, but they still retained the potential to build anything at all, given the appropriate blueprint.

  The construction wires reached across the gap and touched the surface of the Autoverse processors. Maria held her breath, almost expecting to see a defensive reaction, a counterattack. Durham had analyzed the possibilities in advance: if the TVC rules continued to hold true, any “war” between these machines would soon reach a perpetual stalemate; they could face each other forever, annihilating each other’s “weapons” as fast as they grew, and no strategy could ever break the deadlock.

  If the TVC rules failed, though, there was no way of predicting the outcome.

  There was no – detectable – counterattack. The construction wires withdrew, leaving behind data links bridging the gap between the pyramids. Since the map was showing the links as intact, the software must have received some evidence that they were actually working: the Autoverse processors were at least reacting as they should to simple tests of the integrity of the connections.

  Durham said, “Well, that’s something. They haven’t managed to shut us out completely.”

  Repetto grimaced. “You make it sound like the Lambertians have taken control of the processors – that they’re deciding what’s going on here. They don’t even know that this level exists.”

  Durham kept his eyes on the screen. “Of course they don’t. But it still feels like we’re sneaking up on some kind of … sentient adversary. The Lambertians’ guardian angels: aware of all the levels – but jealously defending their own people’s version of reality.” He caught Maria’s worried glance, and smiled. “Only joking.”

  Maria looked on as Durham and Zemansky ran a series of tests to verify that they really had plugged-in to the Autoverse region. Everything checked out – but then, all the same tests had worked when run through the authorized link, down at the hub. The suspect processors were merely acting as messengers, passing data around in a giant loop which confirmed that they could still talk to each other – that the basic structure of the grid hadn’t fallen apart.

  Durham said, “Now we try to stop the clock.” He hit a few keys, and Maria watched his commands racing across the links. She thought: Maybe there was something wrong down at the hub. Maybe this whole crisis is going to turn out to be nothing but a tiny, localized bug. Perfectly explicable. Easily fixed.

  Durham said, “No luck. I’ll try to reduce the rate.”

  Again, the commands were ignored.

  Next, he increased the Autoverse clock rate by fifty per cent – successfully – then slowed it down in small steps, until it was back at the original value.

  Maria said numbly, “What kind of sense does that make? We can run it as fast as we like – within our capacity to give
it computing resources – but if we try to slow it down, we hit a brick wall. That’s just … perverse.”

  Zemansky said, “Think of it from the Autoverse point of view. Slowing down the Autoverse is speeding up Elysium; it’s as if there’s a limit to how fast it can run us – a limit to the computing resources it can spare for us.”

  Maria blanched. “What are you suggesting? That Elysium is now a computer program being run somewhere in the Autoverse?”

  “No. But there’s a symmetry to it. A principle of relativity. Elysium was envisioned as a fixed frame of reference, a touchstone of reality – against which the Autoverse could be declared a mere simulation. The truth has turned out to be more subtle: there are no fixed points, no immovable objects, no absolute laws.” Zemansky betrayed no fear, smiling beatifically as she spoke, as if the ideas enchanted her. Maria longed to know whether she was merely concealing her emotions, or whether she had actually chosen a state of tranquility in the face of her world’s dethronement.

  Durham said flatly, “Symmetries were made to be broken. And we still have the edge: we still know far more about Elysium – and the Autoverse – than the Lambertians do. There’s no reason why our version of the truth can’t make as much sense to them as it does to us. All we have to do is give them the proper context for their ideas.”

  Repetto had created a puppet team of Lambertians he called Mouthpiece: a swarm of tiny robots resembling Lambertians, capable of functioning in the Autoverse – although ultimately controlled by signals from outside. He’d also created human-shaped “telepresence robots” for the four of them. With Mouthpiece as translator, they could “reveal themselves” to the Lambertians and begin the difficult process of establishing contact.

  What remained to be seen was whether or not the Autoverse would let them in.

  Zemansky displayed the chosen entry point: a deserted stretch of grassland on one of Planet Lambert’s equatorial islands. Repetto had been observing a team of scientists in a nearby community; the range of ideas they were exploring was wider than that of most other teams, and he believed there was a chance that they’d be receptive to Elysian theories.