Incandescence

by Greg Egan

  Bard said, "If we have to cut more tunnels, we can do that."

  "And lose more rock? More people?"

  "What choice do we have?" he replied. "Can we pass the Wanderer safely in this state?"

  "I don't know. I don't know how much power we will have lost, I don't know how the whole picture will have changed."

  Roi sent a message to Kem, to be sure that she knew exactly what had happened, and was thinking about these problems. Then she approached Sen again.

  "I need your help," Roi said gently.

  Sen still couldn't get out of her flattened defensive posture; she wanted the walls to hide her, to swallow her.

  "The Splinter is spinning," Roi told her. "The only way I can think of to correct that is to use the baffles in the tunnels, and try to modulate the flows to provide a torque to bring us to a halt."

  Sen struggled to focus. "I think the most stable alignment for the Splinter with respect to the wind would be with the tunnels running rarb-sharq again. In time, we should settle back to that naturally."

  "That sounds likely," Roi said, "but we can't rely on it happening in time. We need to get stabilized as soon as we can."

  "We never planned for this," Sen replied. "Neth and I. We never did the calculations."

  "But you understand her ideas? You can work it out?" Roi had only the crudest notion of Neth's work herself. Even if she found the written notes, it would take her thirty-six shifts to begin to master the theory of wind flow.

  "Perhaps I can do it," said Sen. "Perhaps."

  Bard found a chamber for them to work in, close to an existing light-message route, and set up a control post with Roi, Sen, Haf, and a dozen checkers.

  As the great tunnels swung around, the wind would strike first one side wall, as they approached rarb, and then the other as they turned away from it. If there was any natural effect that would favor one wall in a manner that could halt the spin, Roi couldn't see it operating on the kind of time scale they needed. They would have to try to take control of the flow, using the baffles to ensure that the wind hit the rock with the maximum possible force when it could retard the spin, but passed through the tunnel as smoothly as possible at all other times. Like the imbalance between the garmside and sardside that had carried them away from the Hub, they could try to break the natural symmetry of the situation to work to their advantage.

  Sen struggled with the calculations. There was no shortage of people around her to help with the raw template manipulation, but she was the only one who really grasped Neth's ideas. When her mind grew stale and she needed a diversion to clear her thoughts, Haf did his best to cheer her up, babbling away about his schemes for the future.

  "When we're past the Wanderer, we should build a wall around the Hub," he suggested. "To make sure that whatever happens, no future generation ends up where we are."

  "A wall around the Hub?" Sen made a sound of delighted incredulity. "Made out of what, exactly?"

  "I don't know yet," Haf replied. "But we should move right outside the Hub's curvature, and put the wall so far out that there's no chance of the Hub capturing anyone again."

  "How can we go past the Hub's curvature?" Roi protested. "Even if the Incandescence stretches that far, the wind will be too weak to move us."

  "We'll capture it and push it out ourselves," Haf insisted.

  "How?" asked Sen. "What can push the wind, if not curvature?"

  "What moves our legs?" he countered. "Curvature's got nothing to do with that."

  "So we'll capture the wind. and push it out with our legs?" Sen asked.

  Haf said, "Now you're just being silly."

  Sen's confidence grew, and she completed her calculations. They tested a set of configurations for the baffles, switching between them as the tunnels swung in and out of alignment with the wind. They would have to wait several shifts for the void-watchers to notice any change in their motion compared to the distant lights, but there were people stationed close to the tunnels' walls who could measure the difference in flow coming through the rock, and the general plan did seem to be working: the wind was striking the walls at the right times and places.

  Roi began to feel hopeful again. The deaths and the damage had scarred them all, but it was not the end of the Splinter. If they could realign the tunnels, Kem's calculations gave them a good chance with the Wanderer; they would not need to add to the existing three tunnels, risking more fissures in the rock.

  Confirmation arrived from Ruz; the wayward spin was growing measurably smaller. In each report from the void-watchers that followed, the news became ever more encouraging. They would have to take care as the spin approached zero to ensure that the tunnels ended up in the right orientation, but since each successive prod was only delivered when they were already more or less aligned with the wind, it would take a combination of very bad luck and very poor judgment to end up with the tunnels stranded in a position where they could deliver no power at all.

  It was many shifts after the accident before Roi began thinking about her own work again. There had been too many distractions and responsibilities; a part of her had also been hoping that a long break from the calculations would see her return to them with fresh ideas.

  It was not a new insight that set her back to work, though, but a worrying postscript to one of Ruz's reports on the dwindling spin. "Dark phase shrinking faster than ever," his message said. "Perhaps eighteen shifts left."

  Roi had expected more time. Whether the accident, or their response to it, had somehow hastened their re-immersion, or whether the plane of the Incandescence itself had grown thicker as they moved away from the Hub, the opportunities the Jolt had granted them were about to come to an end.

  The power the tunnels could extract from the wind would be a little stronger, and their worries about food a little less. Since she had no choice in the matter, Roi tried to dwell on the benefits that would flow as the Incandescence reclaimed them.

  The greatest change that was coming, though, was too stark to ignore. The void-watchers could pack up their instruments and start tending crops and herding susk. However great Cho's ingenuity, once the dark phases were gone, surely nothing could enable them to see into the void through the glow of the Incandescence itself.

  One part of their fate was clear now. By the time they approached the Wanderer, the Splinter would once again be blind.

  25

  Rakesh sat in the kitchen of Lahl's Promise, rearranging the rice in front of him with his fork, unable to bring himself to eat. He'd already missed three of his usual after-shift meetings with Zey, and the fourth one was looming. Without a clear answer to her plea, he did not know how he could face her.

  "The Aloof knew all of this, I swear," he told Parantham. "Maybe they followed the trail from the meteor, like we did, or maybe they already knew where it would end. But I don't believe they brought us into the bulge because of dead microbes in a rock. They brought us here to see the state of the Arkdwellers. They brought us here to resolve this problem."

  "That might be true," Parantham conceded. "But what does it change?"

  "It makes me feel used, that's what it changes." Was this the reason Lahl had singled him out, back at the node? She had drilled straight into his soul, seen to the heart of his boredom and frustration, and known how powerfully a request like Zey's would resonate for him?

  "Used, how?" Parantham replied. "You think the Aloof are so morally finicky that they'd decline to throw this genetic switch themselves. but so morally bankrupt that they don't mind contriving a situation where you feel pressured to do it for them? If they wanted to do it, they'd do it. If they were capable of understanding the Arkdwellers' plight, they'd be capable of fixing it."

  "I'm not talking about technology," Rakesh retorted. "Of course they could throw the switch if they wanted to. But they preferred to wash their hands of the matter, and make it someone else's responsibility."

  Parantham seemed genuinely puzzled. "You mean, they asked for a second opinion
on a difficult ethical question, from someone who they hoped would be better qualified? From a cousin of the Arkdwellers, a child of DNA?"

  Rakesh wanted to strangle her.

  Actually, what he wanted most of all was for Parantham to tell him that he had no right to intervene, and that he should leave the Arkdwellers to sleepwalk in peace. It was what he'd expected her to say when she heard Zey's plea. Unfortunately, she'd failed to oblige.

  He tried to back away from all the things that were frustrating him, and analyze the situation calmly one more time.

  "The Arkdwellers had this genetic mechanism forced on them by their ancestors," he said. "But it wasn't done blindly or gratuitously; it carries some very clear advantages. It keeps them satisfied with the status quo when the status quo is working. It spares them the boredom and claustrophobia that they'd otherwise suffer, cooped up in a rock, orbiting a neutron star, with no other safe place to go. But when something comes along to threaten them — a challenge of cosmic proportions, the kind of thing their ancestors faced all the way back to the Steelmakers — their intellectual powers come out of hibernation, and they get the Enlightenment on overdrive."

  Parantham said, "Which is fine as far as it goes, but if some other kind of opportunity comes along — a chance to enlarge their horizons that isn't accompanied by stress and danger — how can they even assess it properly, let alone take advantage of it?"

  "They can't," Rakesh replied. "It's impossible."

  "Except for Zey, and those like her."

  "Yes."

  "But the question then," Parantham said, "is do the exceptional cases have the right to speak for the whole Ark? Zey has her own interests. If she wants to come visit the Amalgam, we can try to oblige her. But is she entitled to drag the whole of her society, without their consent, into her own state of mind?"

  "Were the Arkmakers entitled," Rakesh replied, "to sentence their children to fifty million years of docility? Yes, their intentions were impeccable, and yes, they were acting under pressure, desperately hunting for a way to keep their children alive while a neutron star was bearing down on them. But they couldn't anticipate everything that the future would bring. Maybe they thought that when the next apocalypse-cum-renaissance arrived, their descendants would figure out everything and make a new set of choices for themselves — reengineering their own genome as they saw fit, to suit the next set of challenges. Maybe it was never their intention that their children would end up stranded with this ad hoc solution for so long; they just did their best and hoped that it would tide them over for a couple of million years."

  "Can we be sure, though," Parantham wondered, "that this situation is entirely artificial? What if a similar mechanism had already evolved long before the neutron star approached the home world, and the Arkmakers were merely fine-tuning it?"

  Rakesh said, "So if it's natural, that changes everything?"

  "No, but it's not entirely irrelevant," Parantham replied. "All your drives, all your values, all your priorities come from your biological ancestors. You've removed some drives, and strengthened others, but you didn't sit down one day and say, 'From first principles — ignoring all my inherited traits — what should I be like? How should I live? What should I value?'"

  "All right, I take your point," Rakesh said. "There are no such first principles. I risk plastering my own values all over the Ark. But if the Arkdwellers inherited this long winter of the mind — and some deep part of them cherishes it, the way I cherish various human things for no great, universal reason — they must have inherited the intellectual spring as well. I gave Zey a few simple science lessons; I didn't colonize her brain with nanoware and turn her into something alien. What she represents is a part of everyone's birthright, just as much as the alternative, docile state. It's an accident of circumstances that's put them in a place where that birthright can never be realized again, short of almost certain death. I mean, what's going to tear them away from a neutron star, and still give them time to reboot their culture into a state that will let them defend themselves?"

  Parantham fell silent. Rakesh pushed his plate aside. He could curse the Aloof all he wanted, he could listen to Zey, he could listen to Parantham, but Parantham could debate the pros and cons for a thousand years without coming down on one side. However much he hated it, this was in his hands alone. He could not walk away and pretend that he simply hadn't seen the Ark, or go begging all around the disk for someone else to take responsibility.

  He said, "What if we wake them all to the point where we can communicate with them meaningfully — the way I can communicate with Zey — and then let them choose for themselves? We can grant them an easy way to switch back to the docile mode, individually, if they want to. They can't give consent for what I'm proposing, but putting them in a state where they can understand the question isn't forcing them to remain that way. Zey's state isn't hermetically self-affirming: merely entering it doesn't guarantee that you prefer it. Every individual will still have the power to reflect on their situation, and choose."

  Parantham considered this. "Suppose we do what you suggest. Then what happens next? Those who choose to revert remain in the Ark, obviously, but can they tolerate sharing it with a thousand restless Zeys, when their life doesn't depend on that?"

  "The rest explore the bulge, or come out to the disk with us."

  "Explore the bulge how?" Parantham demanded. "Do we have some promise from the Aloof that they'll have access to the local network?"

  "Well, no," Rakesh conceded.

  "Do we have a promise from the Amalgam that they'll be allowed out into the disk?"

  "You think they'll be refused membership of the Amalgam, just because of the stunt the Aloof pulled with Lahl?"

  Parantham said, "I think it will take a while to negotiate exactly what's going to happen between the bulge and the disk. I think we need to go back and sort out that mess, before we start triggering an intellectual renaissance in a small, crowded place with no escape hatch."

  Rakesh couldn't argue with her central concern. They couldn't light this fire and then walk away, leaving the Arkdwellers to sort out the ensuing conflict. These people were stuck deep in a gravity well, with no planet to mine for materials, and no resources save the meager contents of the Ark itself and the thin plasma of the neutron star's accretion disk. The Arkmakers had envisaged the switch being thrown in a time of crisis, but also a time of opportunity. Without a bridge leading away from the Ark itself, there was no opportunity. Leaving them to stew in their own frustration would be unconscionable.

  "All right," he said, "we have to clear the way to the disk. Go and come back. Hope the idiots in the disk let us out, and then hope the idiots in the bulge let us back in again."

  Parantham nodded, then started laughing with relief. "So that's it? We're agreed? This is your final decision?"

  Rakesh hesitated. It would be thousands of years before they returned. The Ark would survive, and little would have changed, but Zey would be long dead.

  If he went to her with this plan, this promise for the distant future, he knew what she would say. She would beg him to locate the spark in her mind, the thing that made her different from her team-mates, the thing that he had spoken to, nurtured and encouraged, shift after shift.

  Then she would ask him to reach inside her and extinguish it.

  26

  The darkness was gone; the Splinter was immersed in constant brightness again. The light was softer than that in which their journey had begun, its colors less fierce. Everything was gentler, further from the Hub: the wind, the weights, the light. Roi thought: if we'd done this long before the Wanderer came, it might have been a simple, peaceful journey.

  "I never really believed you and Gul," Haf confessed, "when you said you'd grown up without dark phases. How could anyone imagine such a thing?" Roi wasn't sure if he was joking; sometimes it was difficult to tell. "I wonder how it will be for the next generation."

  "Wait and see," Roi replied. Sometimes she
felt like playing along with Haf, joining him in his wild speculations, but lately she was afraid of too much talk about the future, as if any hope put into words was more exposed, more vulnerable, than everyone's unspoken longing for safety.

  In the last few dwindling dark phases, Ruz's team had snatched their final observations from the void. Just as the Splinter sank back into the plane of the Incandescence, the Wanderer's orbit had lost its own traces of elevation; they were confined to the same two dimensions now, locked into a closer, more dangerous dance. If the only thing to fear had been a head-on collision with the Wanderer itself, then the problem would not have been so difficult, but mere proximity could be as fatal as contact. The Wanderer was far hotter and brighter than the Incandescence; if they drew too near, or were struck by one of its flares at close range, the heat could sear right through the shelter of the rock and kill them, as surely as if they'd been standing unprotected on the surface.

  Kem had computed the trajectories for both light and flares, and sketched out the safest passage past the Wanderer's orbit. The twisted curvature of the geometry had a pernicious effect, focusing the danger into places where a simpler analysis might have anticipated safety; the Hub did act as a kind of shelter, but the points to which it offered the greatest protection did not lie directly opposite the Wanderer.

  Kem's laborious calculations had identified the path of least danger; the only problem now was to follow it, without a glimpse of the void to confirm their position. Roi had set up systematic weight measurements, and cycling stones and Rotators in a new Null Chamber; all of this helped quantify their distance from the Hub, but the most crucial information, their angle from the Wanderer, could not be measured this way.

  Sen and her team were monitoring the strength of the wind, and had done their best to calibrate a model linking the characteristics of the flow through the tunnels with the last of the solid data that the void-watchers had been able to gather on the Splinter's changing orbit. The varying density of the Incandescence could not be anticipated, but it could be measured in the wind, moment by moment, and fed into the templates to derive a range of estimates as to the effect the tunnels were having on the Splinter's position and speed.