Diaspora

Yatima glanced hopefully at the star they’d called Weyl. If it wasn’t the last link in the chain, it had to be close. “Eight and a half centuries later, the Diaspora reached Swift. From there, you know as much as I do.”

Paolo said, “Forget Swift. What about Orpheus?”

“Orpheus?”

“Just because your clone didn’t wake there—”

Yatima laughed. “It’s got nothing to do with that. Do you think an ancient, space-faring civilization will want to hear about every last novelty we’ve encountered in our travels?”

Paolo was unswayed. “We wouldn’t be here, if it wasn’t for Orpheus. Orpheus changed everything.”

10. DIASPORA

Carter-Zimmerman polis, Earth

55 721 234 801 846 CST

31 December 3999, 23:59:59.000 UT

Waiting to be cloned one thousand times and scattered across ten million cubic light years, Paolo Venetti relaxed in his favorite ceremonial bathtub: a tiered hexagonal pool set in a courtyard of black marble flecked with gold. Paolo wore full traditional anatomy, uncomfortable garb at first, but the warm currents flowing across his back and shoulders slowly eased him into a pleasant torpor. He could have reached the same state in an instant, by decree, but the occasion seemed to demand the complete ritual of verisimilitude, the ornate curlicued longhand of imitation physical cause and effect.

The sky above the courtyard was warm and blue, cloudless and sunless, isotropic. As the moment of Diaspora approached, a small gray lizard darted across the courtyard, claws scrabbling. It halted by the far edge of the pool, and Paolo marveled at the delicate pulse of its breathing, and watched the lizard watching him, until it moved again, disappearing into the surrounding vineyards. The scape was full of birds and insects, rodents and small reptiles-decorative in appearance, but also satisfying a more abstract aesthetic: softening the harsh radial symmetry of the lone observer; anchoring the simulation by perceiving it from a multitude of viewpoints. Ontological guy lines. No one had asked the lizards if they wanted to be cloned, though. They were coming along for the ride, like it or not.

Paolo waited calmly, prepared for every one of half a dozen possible fates.

11. WANG’S CARPETS

Carter-Zimmerman polis, Orpheus orbit

65 494 173 543 415 CST

10 September 4309, 17:12:20.569 UT

An invisible bell chimed softly, three times. Paolo laughed, delighted. One chime would have meant that he was still on Earth: an anti-climax, certainly—but there would have been advantages to compensate for that. Everyone who really mattered to him lived in Carter-Zimmerman, but not all of them had chosen to take part in the Diaspora to the same degree; his Earth-self would have lost no one. Helping to ensure that the thousand ships were safely dispatched would have been satisfying, too. And remaining a member of the Coalition, plugged into the entire global culture in real time, would have been an attraction in itself.

Two chimes would have meant that this clone of Carter-Zimmerman had reached a planetary system devoid of life. Paolo had run a sophisticated—but nonsentient—self-predictive model before deciding to wake under those conditions. Exploring a handful of alien worlds, however barren, had seemed likely to be an enriching experience for him, with the distinct advantage that the whole endeavor would be untrammeled by the kind of elaborate precautions necessary in the presence of alien life. C-Z’s population would have fallen by more than half, and many of his closest friends would have been absent, but he would have forged new friendships, he was sure.

Four chimes would have signaled the discovery of intelligent aliens. Five, a technological civilization. Six, spacefarers.

Three chimes, though, meant that the scout probes had detected unambiguous signs of life. That was reason enough for jubilation. Up until the moment of the prelaunch cloning—a subjective instant before the chimes had sounded—no reports of even the simplest alien life had reached Earth from the gleisners. There’d been no guarantee that any part of the C-Z Diaspora would find it.

Paolo willed the polis library to brief him; it promptly rewired the declarative memory of his simulated traditional brain with all the information he was likely to need to satisfy his immediate curiosity. This clone of C-Z had arrived at Vega, the second closest of the thousand target stars, twenty-seven light years from Earth. Theirs was the first ship to reach its destination; the ship aimed at Fomalhaut had been struck by debris and annihilated en route. Paolo found it hard to grieve for the ninety-two citizens who’d been awake; he hadn’t been close to any of them prior to the cloning, and the particular versions who’d willfully perished two centuries ago in interstellar space seemed as remote as the victims of Lacerta.

He examined his new home star through the cameras of one of the scout probes—and the strange filters of the ancestral visual system. In traditional colors, Vega was a fierce blue-white disk, laced with prominences. Three times the mass of the sun, twice the size and twice as hot, sixty times as luminous. Burning hydrogen fast, and already halfway through its allotted five hundred million years on the main sequence.

Vega’s sole planet, Orpheus, had been a featureless blip to the best interferometers in the solar system; now Paolo gazed down on its blue-green crescent, ten thousand kilometers below Carter-Zimmerman itself. Orpheus was terrestrial, a nickel-iron-silicate world; slightly larger than Earth, slightly warmer—a billion kilometers took the edge off Vega’s heat—and almost drowning in liquid water. Paolo rushed at a thousand times flesher, allowing C-Z to orbit the planet in twenty subjective tau; daylight unshrouded a broad new swath with each pass. Two slender ocher-colored continents with mountainous spines bracketed hemispheric oceans, and dazzling expanses of pack ice covered both poles—far more so in the north, where jagged white peninsulas radiated out from the midwinter arctic darkness.

The Orphean atmosphere was mostly nitrogen—six times as much as on Earth—with traces of water vapor and carbon dioxide, but not enough of either for a runaway greenhouse effect. The high atmospheric pressure meant reduced evaporation—Paolo saw not a wisp of cloud—and the large, warm oceans in turn helped lock up carbon dioxide. The gamma-ray burst from Lacerta had been even stronger here than on Earth, but with no ozone layer to destroy, and an atmosphere routinely ionized by Vega’s own intense ultraviolet, any change in the chemical environment or the radiation levels at low altitudes would have been relatively minor. The whole system was young by Earth standards, still thick with primordial dust. But Vega’s greater mass, and a denser protostellar cloud, would have meant swifter passage through most of the traumas of birth: nuclear ignition and early luminosity fluctuations; planetary coalescence and the age of bombardments. The library estimated that Orpheus had enjoyed a relatively stable climate, and freedom from major impacts, for at least the past hundred million years.

Long enough for primitive life to appear

A hand seized Paolo firmly by the ankle and tugged him beneath the water. He offered no resistance, and let the vision of the planet slip away. Only two other people in C-Z had free access to this scape—and his father didn’t play games with his now twelve-hundred-year-old son.

Elena dragged him all the way to the bottom of the pool, before releasing his foot and hovering above him, a triumphant silhouette against the bright surface. She was flesher-shaped but obviously cheating; she spoke with perfect clarity, and no air bubbles at all.

“Late sleeper! I’ve been waiting five megatau for this!”

Paolo feigned indifference, but he was fast running out of breath. He had his exoself convert him into an amphibious exuberant—biologically and historically authentic, though none of his own ancestors had taken this form. Water flooded into his modified lungs, and his modified brain welcomed it.

He said, “Why would I want to waste consciousness, sitting around waiting for the scout probes to refine their observations? I woke as soon as the data was unambiguous.” She pummeled his chest; he reached up and pulled her down, instinctively reducing his buoyancy to compensate, and they rolled across the bottom of the pool, kissing.

Elena said, “You know we’re the first C-Z to arrive, anywhere? The Fomalhaut ship was destroyed. So there’s only one other pair of us. Back on Earth.”

“So?” Then he remembered. Elena had chosen not to wake if any other version of her had already encountered life. Whatever fate befell each of the remaining ships, every other version of him would have to live without her.

He nodded soberly, and kissed her again. “What ant I meant to say? You’re a thousand times more precious to me, now?”

“Yes.”

“Ah, but what about the you-and-I on Earth? Five hundred times would he closer to the truth.”

“There’s no poetry in five hundred.”

“Don’t he so defeatist. Rewire your language centers.”

She ran her hands along the sides of his ribcage, down to his hips. They made love with their almost-traditional bodies-and brains; Paolo was amused to the point of distraction when his limbic system went into overdrive, but he remembered enough from the last occasion to bury his self-consciousness and surrender to the strange hijacker. It wasn’t like making love in an civilized fashion—the rate of information exchange between them was minuscule, for a start—but it had the raw insistent quality of most ancestral pleasures.

Then they drifted up to the surface of the pool and lay beneath the radiant sunless sky. Paolo thought: I’ve crossed twenty-seven light years in an instant. I’m orbiting the first planet ever found to hold alien life. And I’ve sacrificed nothing—left nothing I truly value behind. This is too good, too good. He felt a pang of regret for his other selves—it was hard to imagine them faring as well, without Elena, without Orpheus—but there was nothing he could do about that, now. Although there’d be time to confer with Earth before any more ships reached their destinations, he’d decided prior to the cloning not to allow the unfolding of his manifold future to be swayed by any change of heart. Whether or not his Earth-self agreed, the two of them were powerless to alter the criteria for waking. The self with the right to choose for the thousand had passed away.

No matter, Paolo decided. The others would find—or construct—their own reasons for happiness. And there was still the chance that one of them would wake to the sound of four chimes.

Elena said, “if you’d slept much longer, you would have missed the vote.”

The vote? The scouts in low orbit had gathered what data they could about Orphean biology. To proceed any further, it would be necessary to send microprobes into the ocean itself—an escalation of contact which required the approval of two thirds of the polis. There was no compelling reason to believe that the presence of a few million tiny robots could do any harm; all they’d leave behind in the water was a few kilojoules of waste heat. Nevertheless, a faction had arisen that advocated caution. The citizens of Carter-Zimmerman, they argued, could continue to observe from a distance for another decade, or another millennium, refining their observations and hypotheses before intruding… and those who disagreed could always sleep away the time, or find other interests to pursue.

Paolo delved into his library-fresh knowledge of the “carpets,” the sole Orphean lifeform detected so far. They were free-floating creatures living in the equatorial ocean depths—apparently destroyed by UV if they drifted too close to the surface, but sufficiently well-shielded in their normal habitat to have been completely oblivious to Lacerta. They grew to a size of hundreds of meters, then fissioned into dozens of fragments, each of which continued to grow. It was tempting to assume that they were colonies of single-celled organisms, something like giant kelp, but there was no real evidence yet to back that up. It was difficult enough for the scout probes to discern the carpets’ gross appearance and behavior through a kilometer of water, even with Vega’s copious neutrinos lighting the way; remote observations on a microscopic scale, let alone biochemical analyses, were out of the question. Spectroscopy revealed that the surface water was full of intriguing molecular debris, but guessing the relationship of any of it to the living carpets was like trying to reconstruct flesher biochemistry by studying their ashes.

Paolo turned to Elena. “What do you think?”

She moaned theatrically; the topic must have been argued to death while he slept. “The microprobes are harmless. They could tell us exactly what the carpets are made of, without removing a single molecule. What’s the risk? Culture shock?”

Paolo flicked water onto her face, affectionately; the impulse seemed to come with the amphibian body. “You can’t be sure that they’re not intelligent.”

“Do you know what was living on Earth, two hundred million years after it was formed?”

“Maybe cyanobacteria. Maybe nothing. This isn’t Earth, though.”

“True. But even in the unlikely event that the carpets are intelligent, do you think they’d notice the presence of robots a millionth their size? If they’re unified organisms, they don’t appear to react to anything in their environment—they have no predators, they don’t pursue food, they just drift with the currents—so there’s no reason for them to possess elaborate sense organs at all, let alone anything working on a sub-millimeter scale. And if they’re colonies of single-celled creatures, one of which happens to collide with a microprobe and register its presence with surface receptors… what conceivable harm could that do?”

Paolo shrugged. “I have no idea. But my ignorance is no guarantee of safety.”

Elena splashed him back. “The only way to deal with your ignorance is to vote to send down the microprobes. We have to he cautious, I agree, but there’s no point being here if we don’t find out what’s happening in the oceans, right now. I don’t want to wait for this planet to evolve something smart enough to broadcast biochemistry lessons into space. If we’re not willing to take a few infinitesimal risks, Vega will turn red giant before we learn anything.”

It was a throwaway line, but Paolo tried to imagine witnessing the event. In a quarter of a billion years, would the citizens of Carter-Zimmerman be debating the ethics of intervening to rescue the Orpheans—or would they have lost interest and departed for other stars, or modified themselves into beings entirely devoid of nostalgic compassion for organic life?

Grandiose visions for a twelve-hundred-year-old. The Fomalhaut clone had been obliterated by one tiny piece of rock. There was far more junk in the Vegan system than in interstellar space; even ringed by defenses, its data backed up to all the far-flung scout probes, this C-Z was not invulnerable just because it had arrived intact. Elena was right; they had to seize the moment or they might as well retreat into their own hermetic worlds and forget that they’d ever made the journey.

“We can’t lie here forever; the gang’s all waiting to see you.”

“Where?” Paolo felt his first pang of homesickness; on Earth, his circle of friends had always met in a realtime image of the Mount Pinatubo crater, plucked straight from the observation satellites. A recording wouldn’t be the same.

“I’ll show you.”

Paolo reached over and took her hand, then followed her as she jumped. The pool, the sky, the courtyard vanished—and he found himself gazing down on Orpheus again… nightside, but far from dark, with his full mental palette now encoding everything from the pale wash of ground-current long-wave radio to the multicolored shimmer of isotopic gamma rays and backscattered cosmic-ray bremsstrahlung. Half the abstract knowledge the library had fed him about the planet was obvious at a glance, now. The ocean’s smoothly tapered thermal glow spelled three-hundred Kelvin instantly—as well as back-lighting the atmosphere’s tell-tale infrared silhouette.

He was standing on a long, metallic-looking girder. One edge of a vast geodesic sphere, open to the blazing cathedral of space. He glanced up and saw the star-rich dust-clogged band of the Milky Way, encircling him from zenith to nadir; aware of the glow of every gas cloud, discerning each absorption and emission line, Paolo could almost feel the plane of the galactic disk transect him. Some constellations were distorted, but the view was more familiar than strange, and he recognized most of the old signposts by color. Once he had his bearings, the direction they’d taken became clear from the way the nearer stars had gained or lost brightness. The once-dazzling Sirius was the most strikingly diminished, so Paolo searched the sky around it. Five degrees away south, by parochial Earth reckoning—faint but unmistakable: the sun.

Elena was beside him, superficially unchanged, although they’d both shrugged off the constraints of biology. The conventions of this scape mimicked the physics of real macroscopic objects in free-fall and vacuum, but it wasn’t set up to model any kind of chemistry, let alone that of flesh and blood. Their bodies were now just ordinary C-Z icons, solid and tangible but devoid of elaborate microstructure—and their minds weren’t embedded in the scape at all, but were running as pure Shaper in their respective exoselves.

Paolo was relieved to be back to normal. Ceremonial regression to the ancestral form every now and then kept his father happy and being a flesher was largely self-affirming, while it lasted—but every time he emerged from the experience he felt like he’d broken free of billion-year-old shackles. There were polises where the citizens would have found his present structure almost as archaic, but the balance seemed right to Paolo; he enjoyed the sense of embodiment that came from a tactile surface and proprioceptive feedback, but only a fanatic could persist in simulating kilograms of pointless viscera, perceiving every scape through crippled sense organs, and subjugating vis mind to all the unpleasant quirks of flesher neurobiology.

Their friends gathered round, showing off their effortless free-fall acrobatics, greeting Paolo and chiding him for not arranging to wake sooner; he was the last of the gang to emerge from hibernation.

“Do you like our humble new meeting place?” Hermann floated by Paolo’s shoulder, a chimeric cluster of limbs and sense-organs, speaking through the vacuum in modulated infrared. “We call it Satellite Pinatubo. It’s desolate up here, I know, but we were afraid it might violate the spirit of caution if we dared pretend to walk the Orphean surface.”

Paolo glanced mentally at a scout probe’s close-up of a typical stretch of dry land, an expanse of barren red rock. “More desolate down there, I think.” He was tempted to touch the ground—to let the private vision become tactile—but he resisted. Being elsewhere in the middle of a conversation was bad etiquette.

“Ignore Hermann. He wants to flood Orpheus with our alien machinery before we have any idea what the effects might be.” Liesl was a green-and-turquoise butterfly, with a stylized face stippled in gold on each wing.

Paolo was surprised; from the way Elena had spoken he’d assumed that his friends must have come to a consensus in favor of the microprobes, and only a late sleeper, new to the issues, would bother to argue the point. “What effects? The carpets—”

“Forget the carpets! Even if the carpets are as simple as they look, we don’t know what else is down there.” As Liesl’s wings fluttered, her mirror-image faces seemed to glance at each other for support. “With neutrino imaging, we barely achieve spatial resolution in meters, time resolution in seconds. We don’t know anything about smaller lifeforms.”

“And we never will, if you have your way.” Karpal—an ex-gleisner, flesher-shaped as ever—had been Liesl’s lover, last time Paolo was awake.

“We’ve only been here for a fraction of an Orphean year! There’s still a wealth of data we could gather nonintrusively, with a little patience. There might be rare beachings of ocean life—”

Elena said dryly, “Rare indeed. Orpheus has negligible tides, shallow waves, very few storms. And anything beached would he fried by UV before we glimpsed anything more instructive than we’re already seeing in the surface water.”

“Not necessarily. The carpets seem to he vulnerable, but other species might be better protected if they live nearer to the surface. And Orpheus is seismically active; we should at least wait for a tsunami to dump a few cubic kilometers of ocean onto a shoreline, and see what it reveals.”

Paolo smiled; he hadn’t thought of that. A tsunami might be worth waiting for.

Liesl continued, “What is there to lose, by waiting a few hundred Orphean years? At the very least, we could gather baseline data on seasonal climate patterns—and we could watch for anomalies, storms, and quakes, hoping for some revelatory glimpses.”

A few hundred Orphean years? A few terrestrial millennia? Paolo’s ambivalence waned. If he’d wanted to inhabit geological time he would have migrated to the Lokhande polis, where the Order of Contemplative Observers rushed fast enough to watch Earth’s mountains erode in kilotau. Orpheus hung in the sky beneath them, a beautiful puzzle waiting to be decoded, demanding to he understood.

He said, “But what if there are no ’revelatory glimpses'? How long do we wait? We don’t know how rare life is—in time, or in space. If this planet is precious, so is the epoch it’s passing through. We don’t know how rapidly Orphean biology is evolving; species might appear and vanish while we agonize over the risks of gathering better data. The carpets—and whatever else could die out before we’d learned the first thing about them. What a waste that would be!”

Liesl stood her ground.

“And if we damage the Orphean ecology—or culture—by rushing in? That wouldn’t be a waste. It would he a tragedy.”

Paolo assimilated all the stored transmissions from his Earth-self-almost three hundred years’ worth-before composing a reply. The early communications included detailed mind grafts, and it was good to share the excitement of the Diaspora’s launch; to watch-very nearly firsthand-the thousand ships, nanomachine-carved from asteroids, depart in a blaze of annihilation gamma rays. Then things settled down to the usual prosaic matters: Elena, the gang, shameless gossip, Carter-Zimmerman’s ongoing research projects, the buzz of inter-polis cultural tensions, the not-quite-cyclic convulsions of the arts (the perceptual aesthetic overthrows the emotional, again… although Valladas in Konishi polis claims to have constructed a new synthesis of the two).

After the first fifty years, his Earth-self had begun to hold things back; by the time news reached Earth of the Fomalhaut clone’s demise, the messages had become pure gestalt-and-linear monologues. Paolo understood. It was only right; they’d diverged, and you didn’t send mind grafts to strangers.

Most of the transmissions had been broadcast to all of the ships, indiscriminately. Forty-three years ago, though, his Earth-self had sent a special message to the Vega-bound clone.

“The new lunar spectroscope we finished last year has just picked up clear signs of water on Orpheus. There should be large temperate oceans waiting for you, if the models are right. So… good luck.” Vision showed the instrument’s domes growing out of the rock of the lunar farside; plots of the Orphean spectral data; an ensemble of planetary models. “Maybe it seems strange to you, all the trouble we’re taking to catch a glimpse of what you’re going to see in close-up, so soon. It’s hard to explain: I don’t think it’s jealousy, or even impatience. Just a need for independence.

“There’s been a revival of the old debate: with the failure of the wormholes, should we consider redesigning our minds to encompass interstellar distances? One self spanning thousands of stars, not via cloning, but through acceptance of the natural time scale of the lightspeed lag. Millennia passing between mental events. Local contingencies dealt with by non-conscious systems.” Essays, pro and con, were appended; Paolo ingested summaries. “I don’t think the idea will gain much support, though—and the new astronomical projects are something of an antidote. We can watch the stars from a distance, as ever, but we have to make peace with the fact that we’ve stayed behind.

“I keep asking myself, though: where do we go from here? History can’t guide us. Evolution can’t guide us. The C-Z charter says understand and respect the universe… but in what form? On what scale? With what kind of senses, what kind of minds? We can become anything at all—and that space of possible futures dwarfs the galaxy. Can we explore it without losing our way? Fleshers used to spin fantasies about aliens arriving to 'conquer’ Earth, to steal their 'precious’ physical resources, to wipe them out for fear of 'competition'… as if a species capable of making the journey wouldn’t have had the power, or the wit, or the imagination, to rid itself of obsolete biological imperatives. Conquering the galaxy is what bacteria with spaceships would do—knowing no better, having no choice.

“Our condition is the opposite of that: we have no end of choices. That’s why we need to find another spacefaring civilization. Understanding Lacerta is important, the astrophysics of survival is important, but we also need to speak to others who’ve faced the same decisions, and discovered how to live, what to become. We need to understand what it means to inhabit the universe.”

Paolo watched the crude neutrino images of the carpets moving in staccato jerks around his dodecahedral homescape. Twenty-four ragged oblongs drifted above him, daughters of a larger ragged oblong which had just fissioned. Models suggested that shear forces from ocean currents could explain the whole process, triggered by nothing more than the parent reaching a critical size. The purely mechanical break-up of a colony—if that was what it was—might have little to do with the life cycle of the constituent organisms. It was frustrating. Paolo was accustomed to a torrent of data on anything that caught his interest; for the Diaspora’s great discovery to remain nothing more than a sequence of coarse monochrome snapshots was intolerable.

He glanced at a schematic of the scout probes’ neutrino detectors, but there was no obvious scope for improvement. Nuclei in the detectors were excited into unstable high-energy states, then kept there by fine-tuned gamma-ray lasers picking off lower-energy eigenstates faster than they could creep into existence and attract a transition. Changes in neutrino flux of one part in ten-to-the-fifteenth could shift the energy levels far enough to disrupt the balancing act. The carpets cast a shadow so faint, though, that even this near-perfect vision could barely resolve it.

Orlando Venetti said, “You’re awake.”

Paolo turned. His father stood an arm’s length away, presenting as an ornately clad flesher of indeterminate age. Definitely older than Paolo, though; Orlando never ceased to play up his seniority—even if the age difference was only twenty-five percent now, and falling.

Paolo banished the carpets from the room to the space behind one pentagonal window, and took his father’s hand. The portions of Orlando’s mind which meshed with his own expressed pleasure at Paolo’s emergence from hibernation, fondly dwelt on past shared experiences, and entertained hopes of continued harmony between father and son. Paolo’s greeting was similar, a carefully contrived revelation of his own emotional state. It was more of a ritual than an act of communication, but then, even with Elena he set up harriers. No one was totally honest with another person-unless the two of them intended to fuse permanently.

Orlando nodded at the carpets. “I hope you appreciate how important they are.”

“You know I do.” He hadn’t included that in his greeting, though. “First alien life.” C-Z humiliates the gleisner robots, at last—that was probably how his father saw it. The robots had been first to Alpha Centauri, and first to an extrasolar planet, but first life was Apollo to their Sputniks, for anyone who chose to think in those terms.

Orlando said, “This is the hook we need, to catch the citizens of the marginal polises. The ones who haven’t quite imploded into solipsism. This will shake them up—don’t you think?”

Paolo shrugged. Earth’s citizens were free to implode into anything they liked; it didn’t stop Carter-Zimmerman from exploring the physical universe. But even thrashing the gleisners wouldn’t be enough for Orlando; like many carnevale refugees, he had a missionary streak. He wanted every other polis to see the error of its ways, and follow C-Z to the stars.

Paolo said, “Ashton-Laval has intelligent aliens. I wouldn’t be so sure that news of giant seaweed is going to take Earth by storm.”

Orlando was venomous. “Ashton-Laval intervened in its so-called 'evolutionary’ simulations so many time that they might as well have built the end products in an act of creation lasting six days. They wanted talking reptiles, and mirabile dictu, they got talking reptiles. There are self-modified citizens in this polis more alien than the aliens in Ashton-Laval.”

Paolo smiled. “All right. Forget Ashton-Laval. But forget the marginal polises, too. We choose to value the physical world. That’s what defines us, but it’s as arbitrary as any other choice of values. Why can’t you accept that? It’s not the One True Path which the infidels have to be bludgeoned into following.” He knew he was arguing half for the sake of it, but Orlando always drove him into taking the opposite position.

Orlando made a beckoning gesture, dragging the image of the carpets halfway hack into the room. “You’ll vote for the microprobes?”

“Of course.”

“Everything depends on that, now. It’s good to start with a tantalizing glimpse, but if we don’t follow up with details soon they’ll lose interest back on Earth very rapidly.”

“Lose interest? It’ll be fifty-four years before we know whether anyone paid the slightest attention in the first place.”

Orlando regarded him with disappointment. “If you don’t care about the other polises, think about C-Z. This helps us, it strengthens us. We have to make the most of that.”

Paolo was bemused. “What needs to be strengthened? You make it sound like there’s something at risk.”

“There is. What do you think a thousand lifeless worlds would have done to us?”

“Isn’t that entirely academic now? But all right, I agree with you: this strengthens C-Z. We’ve been lucky. I’m glad, I’m grateful. Is that what you wanted to hear?” Orlando said sourly.

“You take too much for granted.”

“And you care too much what I think! I’m not your… heir.” There were times when his father seemed unable to accept that the whole concept of offspring had lost its archaic significance. “You don’t need me to safeguard the future of Carter-Zimmerman on your behalf. Or the future of the whole Coalition. You can do it in person.”

Orlando looked wounded—a conscious choice, but it still encoded something. Paolo felt a pang of regret, but he’d said nothing he could honestly retract.

His father gathered up the sleeves of his gold and crimson robes—the only citizen of C-Z who could make Paolo uncomfortable to be naked—and repeated as he vanished from the room: “You take too much for granted.”

The gang watched the launch of the microprobes together—even Liesl, though she came in mourning, as a giant dark bird. Karpal stroked her feathers nervously. Hermann appeared as a creature out of Escher, a segmented worm with six flesher-shaped feet—on legs with elbows—given to curling up into a disk and rolling along the girders of Satellite Pinatubo. Paolo and Elena kept saying the same thing simultaneously; they’d just made love.

Hermann had moved the satellite into a notional orbit just below one of the scout probes, and changed the scape’s scale so that the probe’s lower surface, an intricate landscape of detector modules and attitude-control jets, blotted out half the sky. The atmospheric-entry capsules, ceramic teardrops three centimeters wide, burst from their launch tube and hurtled past like boulders, vanishing from sight before they’d fallen so much as ten meters closer to Orpheus. It was all scrupulously accurate, although it was part real-time imagery, part extrapolation, part faux. Paolo thought: We might as well have run a pure simulation… and pretended to follow the capsules down. Elena gave him a guilty/admonishing look. Yeah—and then why bother actually launching them at all? Why not just simulate a plausible Orphean ocean full of plausible Orphean lifeforms? Why not simulate the whole Diaspora? There was no crime of heresy in C-Z; the polis charter was just a statement of the founders’ values, not some doctrine to be accepted under threat of exile. At times it still felt like a tightrope walk, though, trying to classify every act of simulation into those which contributed to an understanding of the physical universe (good), those which were merely convenient, recreational, aesthetic (acceptable)… and those which constituted a denial of the primacy of real phenomena (time to think about emigration).

The vote on the microprobes had been close: seventy-two percent in favor, just over the required two-thirds majority, with five percent abstaining. Citizens created since the arrival at Vega were excluded… not that anyone in Carter-Zimmerman would have dreamt of stacking the ballot, perish the thought. Paolo had been surprised at the narrow margin; he was yet to hear a single plausible scenario for the microprobes doing harm. He wondered if there was another, unspoken reason which had nothing to do with fears for the Orphean ecology, or hypothetical culture. A wish to prolong the pleasure of unraveling the planet’s mysteries? Paolo had some sympathy with that impulse, but the launch of the microprobes would do nothing to undermine the greater long-term pleasure of watching, and understanding, as Orphean life evolved.

Liesl said forlornly, “Coastline erosion models show that the north-western shore of Lambda is inundated by tsunami every ninety Orphean years, on average.” She offered the data to them; Paolo glanced at it, and it looked convincing, but the point was academic now. “We could have waited.”

Hermann waved his eye-stalks at her. “Beaches covered in fossils, are they?”

“No, but the conditions hardly—”

“No excuses!” He wound his body around a girder, kicking his legs gleefully. Hermann had been scanned in the twenty-first century, before Carter-Zimmerman even existed, but over the teratau he’d wiped most of his episodic memories and rewritten his personality a dozen times. He’d once told Paolo, “I think of myself as my own great-great-grandson. Death’s not so hard, if you do it incrementally. Ditto for immortality.

Elena said, “I keep trying to imagine how it will feel if another C-Z clone stumbles on something infinitely better—like aliens with shortened wormholes—while we’re back here studying rafts of algae.” Her icon was more stylized than usual: sexless, hairless and smooth, the face inexpressive and androgynous.

Paolo shrugged. “If they can shorten wormholes, the might visit us. Or share the technology, so we can link up the whole Diaspora. But I know what you mean: first alien life, and it’s likely to be about as sophisticated as seaweed. It breaks the jinx, though. Seaweed every twenty-seven light years. Nervous systems every fifty? Intelligence every hundred?” He fell silent, abruptly realizing what she was feeling: electing not to wake again after first life was beginning to seem like the wrong choice, a waste of the opportunities the Diaspora had created. Paolo offered her mind graft expressing empathy and support, but she declined.

She said, “I want sharp borders, right now. I want to deal with this myself.”

“I understand.” He let the partial model of her which he’d acquired as they’d made love fade from his mind, heaving only an ordinary, guesswork-driven Elena-symbol, much like those he possessed for everyone else he knew. Paolo took the responsibilities of intimacy seriously; his lover before Elena had asked him to erase all his knowledge of her, and he’d more or less complied the only thing he still knew about her was the fact that she’d made the request.

Hermann announced, “Planetfall” Paolo glanced at a replay of a scour probe view which showed the first few entry capsules breaking up above the ocean and releasing their microprobes. Nanomachines transformed the ceramic shields (and then themselves) into carbon dioxide and a few simple minerals—nothing the micrometeorites constantly raining down onto Orpheus didn’t contain—before the fragments could strike the water. The microprobes would broadcast nothing; when they’d finished gathering data, they’d float to the surface and modulate their UV reflectivity. It would be up to the scout probes to locate these specks, and read their messages, before they self-destructed as thoroughly as the entry capsules.

Hermann said, “This calls for a celebration. I’m heading for the Heart. Who’ll join me?”

Paolo glanced at Elena. She shook her head. “You go.”

“Are you sure?”

“Yes! Go on.” Her skin had taken on a mirrored sheen; her expressionless face reflected the planet below. “I’m all right. I just want some time to think things through, on my own.”

Hermann coiled around the satellite’s frame, stretching his pale body as he went, gaining segments, gaining legs. “Come on, come on! Karpal? Liesl? Come and celebrate!”

Elena was gone. Liesl made a derisive sound and flapped off into the distance, mocking the scape’s airlessness. Paolo and Karpal watched as Hermann grew longer and faster-and then in a blur of speed and change stretched out to wrap the entire geodesic frame. Paolo jumped away, laughing; Karpal did the same.

Then Hermann constricted like a boa, and snapped the whole satellite apart.

They floated for a while, two flesher-shaped creatures and a giant worm in a cloud of spinning metal fragments, an absurd collection of imaginary debris, glinting by the light of the true stars.

The Heart was always crowded, but it was larger than Paolo had seen it, even though Hermann had shrunk back to his original size so as not to make a scene. The huge muscular chamber arched above them, pulsating wetly in time to the music, as they searched for the perfect location to soak up the atmosphere.

They found a good spot and made some furniture, a table and two chairs—Hermann preferred to stand—and the floor expanded to make room. Paolo looked around, shouting greetings at the people he recognized by sight, but not bothering to check for signatures. Chances were he’d met everyone here, but he didn’t want to spend the next few kilotau exchanging pleasantries with casual acquaintances.

Hermann said, “I’ve been monitoring our modest stellar observatory’s data stream—my antidote to Vegan parochialism. Odd things are going on around Sirius. We’re seeing megaKelvin X-rays, gravity waves… and some unexplained hot spots on Sirius B.” He turned to Karpal and asked innocently, “What do you think those robots are up to? There’s a rumor that they’re planning to drag the white dwarf out of orbit, and use it as part of a giant spaceship.”

“I never listen to rumors.” Karpal always presented as a faithful reproduction of his old gleisner body. Leaving his people and coming into C-Z must have taken considerable courage; they’d never welcome him hack.

Paolo said, “Does it matter what they do? Where they go, how they get there? There’s more than enough room for both of us. Even if they shadowed the Diaspora, even if they came to Vega—we could study the Orpheans together, couldn’t we?”

Hermann’s cartoon insect face showed mock alarm, eyes growing wider, and wider apart. “Not if they dragged along a white dwarf! Next thing they’d want to start building a Dyson sphere.” He turned back to Karpal. “You don’t still suffer the urge, do you, for… astrophysical engineering?”

“Nothing C-Z’s exploitation of a few megatons of Vegan asteroid material hasn’t satisfied.”

Paolo tried to change the subject. “Has anyone heard from Earth, lately? I’m beginning to feel unplugged.” His own most recent message was a decade older than the time lag.

Karpal said, “You’re not missing much; all they’re talking about is Orpheus: the new lunar observations, the signs of water. They seem more excited by the mere possibility of life than we are by the certainty. And they have very high hopes.”

Paolo laughed. “They do. My Earth-self seems to be counting on the Diaspora to find an advanced civilization with the answers to all of the Coalition’s existential problems. I don’t think he’ll get much cosmic guidance from kelp.”

“You know there was a big rise in emigration from C-Z after the launch? Emigration, and suicides.” Hermann had stopped wriggling and gyrating, becoming almost still, a sign of rare seriousness. “I suspect that’s what triggered the astronomy program in the first place. And it seems to have staunched the flow, at least in the short term. Earth C-Z detected water before any clone in the Diaspora—and when they hear that we’ve found life, they’ll feel more like collaborators in the discovery because of it.”

Paolo felt a stirring of unease. Emigration and suicides? Was that why Orlando had been so gloomy? After the disaster of the Forge, and then another three hundred years of waiting, how high had expectations become?

A buzz of excitement crossed the floor, a sudden shift in the tone of the conversation. Hermann whispered, mock-reverentially, “First microprobe has surfaced. And the data is coming in now.”

The non-sentient Heart was intelligent enough to guess its patrons’ wishes. Although everyone could tap the library for results, privately, the music cut out and a giant public image of the summary data appeared, high in the chamber. Paolo had to crane his neck to view it, a novel experience.

The microprobe had mapped one of the carpets in high resolution. The image showed the expected rough oblong, some hundred meters wide—but the two- or three-meter-thick slab of the neutrino tomographs was revealed now as a delicate, convoluted surface—fine as a single layer of skin, but folded into an elaborate space filling curve. Paolo checked the full data: the topology was strictly planar, despite the pathological appearance.

No holes, no joins—just a surface which meandered wildly enough to look ten thousand times thicker from a distance than it really was.

An inset showed the microstructure, at a point which started at the rim of the carpet and then—slowly—moved toward the center. Paolo stared at the flowing molecular diagram for several seconds before he grasped what it meant.

The carpet was not a colony of single-celled creatures. Nor was it a multicellular organism. It was a single molecule, a two-dimensional polymer weighing twenty-five thousand tons. A giant sheet of folded polysaccharide, a complex mesh of interlinked pentose and hexose sugars hung with alkyl and amide side chains. A bit like a plant cell wall, except that this polymer was far stronger than cellulose, and the surface area was twenty orders of magnitude greater.

Karpal said, “I hope those entry capsules were perfectly sterile. Earth bacteria would gorge themselves on this. One big floating carbohydrate dinner, with no defenses.”

Hermann thought it over. “Maybe. If they had enzymes capable of breaking off a piece—which I doubt. No chance we’ll find out, though: even if there’d been bacterial spores lingering in the asteroid belt from early flesher expeditions, every ship in the Diaspora was double-checked for contamination en route. We haven’t brought smallpox to the Americas.”

Paolo was still dazed. “But how does it assemble? How does it… grow?” Hermann consulted the library and replied, before Paolo could do the same.

“The edge of the carpet catalyzes its own growth. The polymer is irregular, aperiodic—there’s no single component which simply repeats. But there seem to be about twenty thousand basic structural units, twenty thousand different polysaccharide building blocks.” Paolo saw them: long bundles of cross-linked chains running the whole two-hundred-micron thickness of the carpet, each with a roughly square cross-section, bonded at several thousand points to the four neighboring units. “Even at this depth, the ocean’s full of UV-generated radicals which filter down from the surface. Any structural unit exposed to the water converts those radicals into more polysaccharide and builds another structural unit.”

Paolo glanced at the library again, for a simulation of the process. Catalytic sites strewn along the sides of each unit trapped the radicals in place, long enough for new bonds to form between them. Some simple sugars were incorporated straight into the polymer as they were created; others were set free to drift in solution for a microsecond or two, until they were needed. At that level, there were only a few basic chemical tricks being used… but molecular evolution must have worked its way up from a few small autocatalytic fragments, first formed by chance, to this elaborate system of twenty thousand mutually self-replicating structures. If the “structural units” had floated free in the ocean as independent molecules, the “lifeform” they comprised would have been virtually invisible. By bonding together, though, they became twenty thousand colors in a giant mosaic.

It was astonishing. Paolo hoped Elena was tapping the library, wherever she was. A colony of algae would have been more “advanced”—but this incredible primordial creature revealed infinitely more about the possibilities for the genesis of life. Carbohydrate, here, played every biochemical role: information carrier, enzyme, energy source, structural material. Nothing like it could have survived on Earth, once there were organisms capable of feeding on it—and if there were ever intelligent Orpheans, they’d he unlikely to find any trace of this bizarre ancestor.

Karpal wore a secretive smile.

Paolo said, “What?”

“Wang tiles. The carpets are made out of Wang tiles.”

Hermann beat him to the library, again. “Wang as in the twentieth-century mathematician, Hao Wang. Tiles as in any set of shapes which can cover the plane. Wang tiles are squares with various shaped edges, which have to fit complementary shapes on adjacent squares. You can cover the plane with a set of Wang tiles, as long as you choose the right one every step of the way. Or in the case of the carpets, grow the right one.”

Karpal said, “We should call them Wang’s Carpets, in honor of Hao Wang. After twenty-three hundred years, his mathematics has come to life.”

Paolo liked the idea, but he was doubtful. “We may have trouble getting a two-thirds majority on that. It’s a bit obscure.”

Hermann laughed. “Who needs a two-thirds majority? If we want to call them Wang’s Carpets, we can call them Wang’s Carpets. There are ninety-seven languages in current use in C-Z—half of them invented since the polis was founded. I don’t think we’ll be exiled for coining one private name.”

Paolo concurred, slightly embarrassed. The truth was, he’d completely forgotten that Hermann and Karpal weren’t actually speaking Modern Roman.

The three of them instructed their exoselves to consider the name adopted: henceforth, they’d hear “carpet” as “Wang’s Carpet”—but if they used the term with anyone else, the reverse translation would apply.

Orlando’s celebration of the microprobe discoveries was very much a carnevale-refugee affair. The scape was an endless sunlit garden strewn with tables covered in food, and the invitation had politely suggested attendance in strict ancestral form. Paolo politely faked it, simulating most of the physiology but running the body as a puppet, leaving his mind unshackled.

He drifted from table to table, sampling the food to keep up appearances, wishing Elena had come. There was little conversation about the biology of Wang’s Carpets; most of the people here were simply celebrating their win against the opponents of the microprobes—and the humiliation that faction would suffer, now that it was clearer than ever that the “invasive” observations could have done no harm. Liesl’s fears had proved unfounded; there was no other life in the ocean, just Wang’s Carpets of various sizes. Paolo, feeling perversely even-handed after the fact, kept wanting to remind these smug movers and shakers: There might have been anything down there. Strange creatures, delicate and vulnerable in ways we could never have anticipated. We were lucky, that’s all.

He ended up alone with Orlando almost by chance; they were both fleeing different groups of appalling guests when their paths crossed on the lawn.

Paolo asked, “How do you think they’ll take this, back home?”

“It’s first life, isn’t it? Primitive or not. It should at least maintain interest in the Diaspora, until the next alien biosphere is discovered.” Orlando seemed subdued; perhaps he was finally coming to terms with the gulf between their modest discovery and Earth’s longing for world-shaking results. “And at least the chemistry is novel. If it had turned out to be based on DNA and protein, I think half of Earth C-Z would have died of boredom on the spot. Let’s face it, the possibilities of DNA have been simulated to death.”

Paolo smiled at the heresy. “You think if nature hadn’t managed a little originality, it would have dented people’s faith in the charter? If the solipsist polises had begun to look more inventive than the universe itself… ”

“Exactly.”

They walked on in silence, then Orlando halted, and turned to face him. “There’s something I’ve been meaning to tell you. My Earth-self is dead.”

“What?”

“Please, don’t make a fuss.”

“But… why? Why would he?” Dead meant suicide; there was no other cause. “I don’t know why. Whether it was a vote of confidence in the Diaspora”—Orlando had chosen to wake only in the presence of alien life—“or whether he despaired of us sending back good news, and couldn’t face the waiting, and the risk of disappointment. He didn’t give a reason. He just had his exoself send a message, stating what he’d done.”

Paolo was shaken. “When did this happen?”

“About fifty years after the launch.”

“My Earth-self said nothing.”

“It was up to me to tell you, not him.”

“I wouldn’t have seen it that way.”

“Apparently, you would have.”

Paolo fell silent, confused. How was he supposed to mourn a distant version of Orlando, in the presence of the one he thought of as real? Death of one clone was a strange half-death, a hard thing to come to terms with. His Earth-self had lost a father; his father had lost an Earth-self. What exactly did that mean to him?

What Orlando seemed most concerned about was the culture of Earth C-Z. Paolo said carefully, “Hermann told me there’d been a rise in emigration and suicide. But morale has improved a lot since the spectroscope picked up signs of Orphean water, and when they hear that it’s more than just water—”

Orlando cut him off sharply. “You don’t have to talk things up for me. I’m in no danger of repeating the act.” They stood on the lawn, facing each other. Paolo composed a dozen different combinations of mood to communicate, but none of them felt right. He could have granted his father perfect knowledge of everything he was feeling—but what exactly would that knowledge have conveyed? In the end, there was fusion, or separateness. There was nothing in between.

Orlando said, “Kill myself—and leave the fate of the Coalition in your hands? You must he out of your fucking mind.”

They walked on together, laughing.

Karpal seemed barely able to gather his thoughts enough to speak. Paolo would have offered him a mind graft promoting tranquillity and concentration—distilled from his own most focused moments—but he was sure that Karpal would never have accepted it. He said, “Why don’t you just start wherever you want to? I’ll stop you if you’re not making sense.”

Karpal looked around the white dodecahedron with an expression of disbelief. “You live here?”

“Some of the time.”

“But this is your homescape? No trees? No sky? No furniture?”

Paolo refrained from repeating any of Hermann’s naive-robot jokes. “I add them when I want them. You know, like… music. Look, don’t let my taste in decor distract you—”

Karpal made a chair and sat down heavily.

He said, “Hao Wang proved a powerful theorem, twenty-three hundred years ago. Think of a row of Wang Tiles as being like the data tape of a Turing Machine.” Paolo had the library grant him knowledge of the term; it was the original conceptual form of a generalized computing device, an imaginary machine which moved back and forth along a limitless one-dimensional data tape, reading and writing symbols according to a given set of rules.

“With the right set of tiles, to force the right pattern, the next row of the tiling will look like the data tape after the Turing Machine has performed one step of its computation. And the row after that will be the data tape after two steps, and so on. For any given Turing Machine, there’s a set of Wang Tiles that can imitate it.”

Paolo nodded amiably. He hadn’t heard of this particular quaint result, but it was hardly surprising. “The carpets must be carrying out billions of acts of computation every second… but then, so are the water molecules around them. There are no physical processes that don’t perform arithmetic of some kind.”

“True. But with the carpets, it’s not quite the same as random molecular motion.”

“Maybe not.”

Karpal smiled, but said nothing.

“What? You’ve found a pattern? Don’t tell me: our set of twenty thousand polysaccharide Wang Tiles just happens to form the Turing Machine for calculating pi.”

“No. What they form is a universal Turing Machine. They can calculate anything at all—depending on the data they start with. Every daughter fragment is like a program being fed to a chemical computer. Growth executes the program.”

“Ah.” Paolo’s curiosity was roused—but he was having some trouble picturing where the hypothetical Turing Machine put its read/write head. “Are you telling me only one tile changes between any two rows, where the ’machine’ leaves its mark on the ’data tape'… The mosaics he’d seen were a riot of complexity, with no two rows remotely the same.

Karpal said, “No, no. Wang’s original example worked exactly like a standard Turing Machine, to simplify the argument… but the carpets are more like an arbitrary number of different computers with overlapping data, all working in parallel. This is biology, not a designed machine—it’s as messy and wild as, say, a mammalian genome. In fact, there are mathematical similarities with gene regulation: I’ve identified Kauffman networks at every level, from the tiling rules up; the whole system’s poised on the hyperadaptive edge between frozen and chaotic behavior.”

Paolo absorbed that, with the library’s help. Like Earth life, the carpets seemed to have evolved a combination of robustness and flexibility which would have maximized their power to take advantage of natural selection. Thousands of different autocatalytic chemical networks must have arisen soon after the formation of Orpheus, but as the ocean chemistry and the climate changed in the Vegan system’s early traumatic millennia, the ability to respond to selection pressure had itself been selected for, and the carpets were the result. Their complexity seemed redundant, now, after a hundred million years of relative stability—and no predators or competition in sight—but the legacy remained.

“So if the carpets have ended up as universal computers… with no real need anymore to respond to their surroundings… what are they doing with all that computing power?”

Karpal said solemnly, “I’ll show you.”

Paolo followed him into a scape where they drifted above a schematic of a carpet, an abstract landscape stretching far into the distance, elaborately wrinkled like the real thing, but otherwise heavily stylized, with each of the polysaccharide building blocks portrayed as a square tile with four different colored edges. The adjoining edges of neighboring tiles bore complementary colors—to represent the complementary, interlocking shapes of the borders of the building blocks.

“One group of microprobes finally managed to sequence an entire daughter fragment,” Karpal explained, “although the exact edges it started life with are largely guesswork, since the thing was growing while they were trying to map it.” He gestured impatiently, and all the wrinkles and folds were smoothed away, an irrelevant distraction. They moved to one border of the ragged-edged carpet, and Karpal started the simulation running.

Paolo watched the mosaic extending itself, following the tiling rules perfectly—an orderly mathematical process, here: no chance collisions of radicals with catalylytic sites, no mismatched borders between two newgrown neighboring “tiles” triggering the disintegration of both. Just the distillation of the higher-level consequences of all that random motion.

Karpal led Paolo up to a height where he could see subtle patterns being woven, overlapping multiplexed periodicities drifting across the growing edge, meeting and sometimes interacting, sometimes passing right through each other. Mobile pseudo-attractors, quasi-stable waveforms in a one-dimensional universe. The carpet’s second dimension was more like time than space, a permanent record of the history of the edge.

Karpal seemed to read his mind. “One dimensional. Worse than flatland. No connectivity, no complexity What can possibly happen in a system like that? Nothing of interest, right?” He clapped his hands and the scape exploded around Paolo. Trails of color streaked across his sensorium, entwining, then disintegrating into luminous smoke.

“Wrong. Everything goes on in a multidimensional frequency space. I’ve Fourier-transformed the edge into over a thousand components, and there’s independent information in all of them. We’re only in a narrow cross section here, a sixteen-dimensional slice—but it’s oriented to show the principal components, the maximum detail.”

Paolo spun in a blur of meaningless color, utterly lost, his surroundings beyond comprehension. “You’re a gleisner robot, Karpal! Only sixteen dimensions! How can you have done this?”

Karpal sounded hurt, wherever he was. “Why do you think I came to C-Z? I thought you people were flexible!”

“What you’re doing is…” What? Heresy? There was no such thing. Officially. “Have you shown this to anyone else?”

“Of course not. Who did you have in mind? Liesl? Hermann?”

“Good. I know how to keep my mouth shut.” Paolo jumped back to the dodecahedron; Karpal followed. “How can I put this? The physical universe has three spatial dimensions, plus time. Citizens of Carter-Zimmerman inhabit the physical universe. The false promises of Kozuch Theory kept us from the stars for a thousand years. Higher-dimensional mind games are strictly for the solipsists.” Even as he said it, he realized how pompous he sounded.

Karpal replied, more bemused than offended, “It’s the only way to see what’s going on. The only sensible, way to apprehend it. Don’t you want to know what the carpets are actually like?”

Paolo felt himself being tempted. Inhabit a sixteen dimensional slice of a thousand-dimensional frequency space? But it was in the service of understanding a real physical system—not a novel experience for its own sake.

And nobody had to find out.

He ran a quick self-predictive model. There was a ninety-three percent chance that he’d give in, after a kilotau spent agonizing over the decision. It hardly seemed fair to keep Karpal waiting that long.

He said, “You’ll have to loan me your mind-shaping algorithm. My exoself wouldn’t know where to begin.

When it was done, he steeled himself, and jumped back into Karpal’s scape. For a moment, there was nothing but the same meaningless blur as before.

Then everything suddenly crystallized.

Creatures swain around them, elaborately branched tubes like mobile coral, vividly colored in all the hues of Paolo’s mental palette—Karpal’s attempt to cram in some of the information that a mere sixteen dimensions couldn’t show. Paolo glanced down at his own body; nothing was missing, but he could see around it in all the thirteen dimensions in which it was nothing but a pinprick. He quickly looked away. The “coral” seemed far more natural to his altered sensory map, occupying space in all directions, and shaded with hints that it occupied much more. Paolo had no doubt that it was “alive"; it looked more organic than the carpets themselves, by far.

Karpal said, “Every point in this space encodes some kind of quasi-periodic pattern in the tiles. Each dimension represents a different characteristic size—like a wavelength, although the analogy’s not precise. The position of each dimension represents other attributes of the pattern, relating to the particular tiles it employs. So the localized systems you see around you are clusters of a few billion patterns with broadly similar attributes at similar wavelengths.”

They moved away from the swimming coral, into a swarm of something like jellyfish: floppy hyperspheres waving wispy tendrils (each one of them more substantial than Paolo). Tiny jewel-like creatures darted among them. Paolo was just beginning to notice that nothing moved here like a solid object drifting through normal space; motion seemed to entail a shimmering deformation at the leading hypersurface, a visible process of disassembly and reconstruction.

Karpal led him on through the secret ocean. There were helical worms, coiled together in groups of indeterminate number—each single creature breaking up into a dozen or more wriggling slivers, and then recombining… although not always from the same parts. There were dazzling multicolored stemless flowers, intricate hypercones of “gossamer-thin” fifteen-dimensional petals—each one a hypnotic fractal labyrinth of crevices and capillaries. There were clawed monstrosities, writhing knots of sharp insectile parts like an orgy of decapitated scorpions.

Paolo said, uncertainly, “You could give people a glimpse of this in just three dimensions. Enough to make it clear that there’s… life in here. This is going to shake them up badly, though.” Life-embedded in the accidental computations of Wang’s Carpets, with no possibility of ever relating to the world outside. This was an affront to Carter-Zimmerman’s whole philosophy: if nature had evolved “organisms” as divorced from reality as the inhabitants of the most inward-looking polis, where was the privileged status of the physical universe, the clear distinction between reality and illusion? And after three hundred years of waiting for good news from the Diaspora, how would they respond to this back on Earth?

Karpal said, “There’s one more thing I have to show you ”

He’d named the creatures squid, for obvious reasons. They were prodding each other with their tentacles in a way that looked thoroughly carnal. Karpal explained, “There’s no analogue of light here. We’re viewing all this according to ad hoc rules which have nothing to do with the native physics. All the creatures here gather information about each other by contact alone-which is actually quite a rich means of exchanging data, with so many dimensions. What you’re seeing is communication by touch.”

“Communication about what?”

“Just gossip, I expect. Social relationships.”

Paolo stared at the writhing mass of tentacles.

“You think they’re conscious?”

Karpal, point-like, grinned broadly. “They have a central control structure, with more connectivity than a citizen’s brain, which correlates data gathered from the skin. I’ve mapped that organ, and I’ve started to analyze its function.”

He led Paolo into another scape, a representation of the data structures in the “brain” of one of the squid. It was—mercifully—three-dimensional, and highly stylized, with translucent colored blocks to represent mental symbols, linked by broad lines indicating the major connections between them. Paolo had seen similar diagrams of citizens’ minds; this was far less elaborate, but eerily familiar nonetheless.

Karpal said, “Here’s the sensory map of its surroundings. Full of other squid’s bodies, and vague data on the last known positions of a few smaller creatures. But you’ll see that the symbols activated by the physical presence of the other squid are linked to these” —he traced the connection with one finger— “representations. Which are crude miniatures of this whole structure here.”

“This whole structure” was an assembly labeled with gestalt tags for memory retrieval, simple tropisms, short-term goals. The general business of being and doing.

“The squid has maps, not just of other squid’s bodies, but their minds as well. Right or wrong, it certainly tries to know what the others are thinking about. And” —he pointed out another set of links, leading to another, less crude, miniature squid mind— “it thinks about its own thoughts as well. I’d call that consciousness, wouldn’t you?”

Paolo said weakly, “You’ve kept all this to yourself? You came this far, without saying a word—?”

Karpal was chastened. “I know it was selfish, but once I’d decoded the interactions of the tile patterns, I couldn’t tear myself away long enough to start explaining it to anyone else. Arid I came to you first because I wanted your advice on the best way to break the news.”

Paolo laughed bitterly. “The best way to break the news that first alien consciousness is hidden deep inside a biological computer? That everything the Diaspora was meant to prove to the rest of the Coalition has been turned on its head? The best way to explain to the citizens of Carter-Zimmerman that after a three-hundred-year journey, they might as well have stayed on Earth running simulations with as little resemblance to the physical universe as possible?”

Karpal took the outburst in good humor. “I was thinking more along the lines of the best way to point out that if we hadn’t traveled to Orpheus and studied Wang’s Carpets, we’d never have had the chance to tell the solipsists of Ashton-Laval that all their elaborate invented lifeforms and exotic imaginary universes pale into insignificance compared to what’s really out here—and which only the Carter-Zimmerman Diaspora could have found.”

Paolo and Elena stood together on the edge of Satellite Pinatubo, watching one of the scout probes aim its maser at a distant point in space. Paolo thought he saw a faint scatter of microwaves from the beam as it made its way out through Vegas halo of iron-rich dust. Elena’s mind being diffracted all over the cosmos? Best not to think about that.

He said, “When you meet the other versions of me who haven’t experienced Orpheus, I hope you’ll offer them mind grafts so they won’t be jealous.”

She frowned. “Ah. Will I or won’t I? You should have asked me before I cloned myself. No need for your clones to be jealous, though. There’ll be worlds far stranger than Orpheus.”

“I doubt it. You really think so?”

“I wouldn’t be doing this if I didn’t believe that.” Elena had no power to change the fate of the frozen clones of her previous self. But everyone had the right to emigrate.

Paolo took her hand. The beam had been aimed almost at Regulus, UV-hot and bright, but as he looked away, the cool yellow light of the sun caught his eye.

Vega C-Z was taking the news of the squid surprisingly well, so far. Karpal’s way of putting it had cushioned the blow: it was only by traveling all this distance across the real, physical universe that they could have made such a discovery—and it was amazing how pragmatic even the most doctrinaire citizens had turned out to be. Before the launch, “alien solipsists” would have been the most unpalatable idea imaginable, the most abhorrent thing the Diaspora could have stumbled upon—but now that they were here, and stuck with the fact of it, people were finding ways to view it in a better light. Orlando had even proclaimed, “This will be the perfect hook for the marginal polises. 'Travel through real space to witness a truly alien virtual reality.’ We can sell it as a synthesis of the two world views.”

Paolo still feared for Earth, though, where his Earth-self and others were waiting in hope of guidance. Would they take the message of Wang’s Carpets to heart, and retreat into their own hermetic worlds, oblivious to physical reality? Lacerta could he survived, anything could be survived: all you had to do was bury yourself deep enough.

He said plaintively, “Where are the aliens, Elena? The ones we can meet? The ones we can talk to? The ones we can learn from?”

“I don’t know.” She laughed suddenly.

“What?”

“It just occurred to me. Maybe the squid are asking themselves exactly the same question.”