Edges

by Linda Nagata

  Of all the Apparatchiks, the Mathematician looked the most like Urban, even dressed like him in dark, simple clothing—not as any kind of acknowledgment of common origin, but because he just didn’t care about appearance and could not be bothered to modify it. In personality he was reserved and reticent, but he spoke now, explaining, “Shifting the fleet’s course and slowing its momentum will reduce the danger, but not eliminate it. The debris field will have inherited Pytheas’s momentum. It will continue to coast on the fleet’s original heading, even as dispersive forces contend against the exotic physics of the reef. It might be years before the threat is left behind.”

  Urban nodded agreement. Like he’d said, he’d been through this before.

  On the video, the blue sparks dimmed. After several more seconds, they disappeared, leaving nothing visible to mark the shattered remains of Pytheas.

  “Gone dark,” Kona said. “But still a threat. Can we implement a radar system to try to map the debris?”

  “As the distance decreases we should be able to track the larger fragments,” the Engineer said. “But fragments too small to be detected can still cause critical damage to the outriders.”

  The danger was unseen and would remain unknowable, but it was all too real. Urban envisioned the lost outrider as a revenant spray of kinetic projectiles hurtling through the void, with some small but critical percentage of them speeding along trajectories that would inevitably take them toward the trailing ships in the fleet.

  <><><>

  Clemantine duplicated her ghost.

  She sent one version to the high bridge where she listened to the braided conversations of the philosopher cells as they analyzed the loss of Pytheas and debated the value of different mathematical models meant to predict the dispersion of debris.

  Her other ghost she sent into the library’s circular research room, where stacks of files surrounded her. She summoned the Scholar.

  On the main floor of the library the Apparatchiks always appeared confined within the virtual space of a frame, but here among the stacks, the Scholar instantiated without any such restriction. He stood facing her, dressed in what she considered a formal fashion: a long, loose, dark-blue tunic and voluminous trousers of the same color.

  The Scholar was the Apparatchik who looked the least like Urban. His aspect was older, his features sharper, his eyes a strange violet gray, and he’d styled his hair so that it was smooth and long. Tied at the back of his head, it reached his waist.

  “I want to know more about the first time an outrider was lost,” Clemantine told him.

  He eyed her with an unsettling intensity, and then nodded. “I have a brief report prepared for you.” He touched a file, seemingly at random, and a door opened onto another circular room. “Follow, please.”

  She traded subminds with her ghost on the high bridge, where her attention was caught by a centuries-old memory brought into play among a cluster of philosopher cells. The memory circulated as more and more individual cells found value in it and passed it on. It was a study of ballistic motion, like the simulations tracking Pytheas’s debris field—a chaotic, tumbling collision of particles ranging in size from dust motes to meter-wide lumps—but this played out far more quickly.

  It came to her: Like her, the philosopher cells were interested in the history of that first lost outrider. They were using remembered data from that original incident to test a new mathematical model meant to predict the dispersion of debris.

  Ahead of her, the Scholar stepped through the open doorway into another room within the library. Clemantine followed him, but drew back when she saw Vytet already there—this new Vytet, not the Vytet she remembered—and Vytet looked equally taken aback by the sudden company.

  In all the vastness of the library, what were the odds of running into someone else? Excellent, if both were chasing the same topic.

  Vytet recovered his composure first, saying, “This room is devoted to Khonsu, both the ancient deity and the outrider that bears its name. I expect we’re both here for that reason.”

  His low voice disturbed her. She was too accustomed to thinking of him as a woman. She had liked him that way. “So you decided to go over to the other side,” she said, striving for a humorous tone. Mostly failing.

  His smile was sharp-edged. “I like the shift of perspective. It forces me to see things from a different point of view. You should try it sometime.”

  “I’m good. Thank you.”

  Ignoring this exchange, the Scholar touched a file, again seemingly at random. A screen unfolded from it, displaying an unfamiliar starfield. After a few seconds, Clemantine saw a distant flare of blue light. The Scholar pointed, saying, “There. That is the moment the outrider that first bore the name of Khonsu was lost.” After several more seconds, blue sparks appeared, marking the remnants of the shattered reef.

  “The dispersion of the debris was monitored and mapped to the extent possible,” the Scholar explained as the video transitioned to show the hypothesized spread.

  Clemantine nodded. From her post on the high bridge, she’d already seen a model of Khonsu’s debris field—one sketched with more certainty than this. In the Scholar’s rendition, most of the fragments were transparent, barely there, reflecting a lack of certainty in their positions or maybe their existences. But both models depicted objects subject to an unnatural physics, following curved paths, even spiraling around each other, as if drawn by magnetism or an unaccountable gravity, before tumbling apart and disappearing.

  The Scholar said, “We believe that at this point the fragments of the reef expired.”

  Clemantine eyed the time scale in the corner of the display. “After just a few hours?” she asked.

  The Scholar confirmed this with a nod. “We were unable to track the debris after that point.”

  On the high bridge, currents of thought wove across the cell field, coalescing, diverging. Several threads considered the existence of a new ancillary ship already growing within Dragon’s tissue.

  A ship?

  Clemantine’s surprise at this concept bled out into the cells, where it ignited a responding suspicion. She remembered then: It’s not a ship. It’s the gee deck.

  The philosopher cells had been deceived into perceiving the deck as a nascent ship—that was its camouflage—but Clemantine had stumbled, introducing doubt, and now the philosopher cells were questioning the legitimacy of the nascent ship.

  She needed to correct that, soothe their doubt, allay suspicion—but Urban got there first with a concise argument that flooded the field from a hundred thousand points:

  – negate that! –

  Suspicion collapsed. Doubt evaporated. The focus of conversation shifted back to the dispersion of debris.

  A submind brought the memory of this incident to the library. Clemantine pursed her ghost lips, annoyed with Urban for stepping in so quickly, but intrigued by the vision of an ancillary ship growing within Dragon’s tissue.

  Vytet was saying, “Can this be right? An interval of fourteen days before the second ship was lost?”

  “That is correct,” the Scholar confirmed. “That second ship was Artemis. At the time, it was the closest outrider to Khonsu.”

  The Mathematician had warned the debris could remain a hazard for years, but Clemantine was skeptical. “Your model shows the reef affecting the debris for only the first few hours. The dispersion would follow standard physics after that. Surely, after fourteen days, it would be spread too thin to constitute a hazard. Is it possible the fleet was passing through a pre-existing debris field? The shattered remnants of a lost comet or an asteroid? And that both impacts were caused by that primordial hazard?”

  “That would be an extremely unlikely occurrence,” the Scholar said. “But it cannot be ruled out.”

  Vytet shook his head, the dark-red pelt of his hair a helmet framing his intense expression. “I don’t think that theory is any more unlikely than the idea that some fragment of debris, after fourteen days adri
ft, just chanced to intersect the course of an outrider.”

  “So really, we don’t know what happened that first time,” Clemantine said. “And that means we have no idea what level of risk we’re facing now.”

  “In my judgment,” the Scholar said, “that is an accurate assessment.”

  She pressed a knuckle to her chin and, thinking out loud, she mused, “I wonder if Urban will want to replace Pytheas?” Doubt intruded. “I wonder if he can? The philosopher cells perceive the gee deck as an ancillary ship under construction. Would they be willing to support two growing ships?”

  The Scholar drew back, looking uneasy, unsure—just a brief slip before he restored his habitual stern expression, but enough to stir in her a vague suspicion.

  “It has been done before,” he assured her, gentle-voiced, as if explaining things to a child.

  Clemantine wanted details, but Vytet’s enthusiasm was engaged. He jumped back into the conversation, declaring, “I’ve always meant to look into this process. It’s astonishing to think that Dragon has given up enough mass to produce the six original outriders and the two replacements.”

  Clemantine cocked her head. Vytet was right. It was astonishing. So much so that something felt off. Her initial suspicion deepened. “All that,” she said thoughtfully, “and yet Dragon remains such a large courser. How much larger was this ship when Urban first hijacked it?”

  To her astonishment, the Scholar shrugged—a dismissive gesture, foreign to his usual formal manner. “Early records are incomplete,” he explained. “But this venture has always operated on the edge of possibility.”

  Did he mean that as a philosophical answer?

  Clemantine traded a puzzled look with Vytet. “In my experience, a massive courser escorted by six outriders constitutes a formidable fleet. I don’t call that operating on the edge.”

  Vytet nodded agreement. “Mass will always be a limiting factor, but Urban must have felt very comfortable with Dragon’s reserves, since he chose to replace both lost ships.”

  “All lost ships must be replaced,” the Scholar said. “The sensing capability of the fleet is essential. Without it, Dragon would be vulnerable to a stealth approach from a true Chenzeme starship.”

  On the Null Boundary Expedition Clemantine had witnessed just that kind of stealth approach. Her ghost existence did not prevent a shiver as she remembered it. “By the Unknown God,” she murmured. “Near or far, I hope to never see another Chenzeme starship again.”

  <><><>

  Urban used radar to study the span and the composition of the debris field, but he was able to detect only a handful of objects, widely scattered. None posed a threat to the fleet.

  The Pilot said: *I need Pytheas to be replaced.

  *It will be, Urban assured him. *In time.

  The outriders held backups of Dragon’s library, but they served primarily as scouts and watch posts. All were part of Dragon’s telescope array. With Pytheas gone, the Pilot’s oversight of the Near Vicinity was degraded.

  *It will be replaced in less time if we initiate growth now, the Pilot carped.

  Urban strove to keep his voice soothing and reasonable. *You know the gee deck has reduced our reserves of essential elements. You know the Engineer has advised against initiating growth of a new outrider until those elements can be replaced.

  *The Engineer offered a second option.

  *I’m not going to cannibalize the gee deck, Urban told him.

  By the Unknown God, Clemantine would kill him if he undid all their work of the past two years. The gee deck needed to be finished.

  He told the Pilot, *You know I have to balance multiple priorities. Use what you have. Monitor the Near Vicinity as best you can.

  <><><>

  After a day, when there was nothing more to see or do, Clemantine retired again to the archive. As before, her ghost roused at regular intervals to conduct a routine status check of the ship.

  Urban tracked her ghost during those inspection tours, each lasting less than a minute. He adjusted his time sense to match the time that she perceived, even as he remained aware of every second, every hour, every day that slipped past.

  Five days, and then ten, and then fourteen.

  The first time Urban had lost outriders, fourteen days had separated the two incidents. This time, the fourteenth day passed quietly. The fifteenth day followed it, and then the sixteenth.

  Twenty days went by. Then thirty. Forty. Fifty. Sixty.

  Urban dared to believe they’d be all right.

  Then the sixty-third day arrived and his sanguine belief shattered. From his post on the high bridge, he saw the explosion—a diaphanous flash of blue light so brilliant, so close, he knew it was Khonsu, the last outrider in his vanguard, closest to Dragon.

  He adopted the protective filter of the Sentinel, aloof and untouchable, as a fearsome debate raged among the philosopher cells.

  The temperament of the cells was forever malign, aggressively hateful, imbued with unrelenting anger. No gentleness in them, no sense of wonder or awareness of the magnificence of creation. They were a machine mind tasked with carrying out the genocide of technological species. Nothing more. Nothing less.

  They’d captured the explosion of Khonsu in memory. Now they replayed the event, over and over, analyzing every aspect of it. Urban felt the intellectual effort as they fought to develop an explanation for the incident, and to determine what the potential threat might be.

  Clemantine’s ghost joined him on the high bridge. *This shouldn’t have happened, she messaged. He felt her anger, even against the agitation of the cell field.

  *It’s not over, he warned her.

  *Sooth. What happens when the cell field is damaged by debris?

  *We keep control, he warned her. *Regardless of what happens.

  The philosopher cells comprehended the threat. They monitored the expansion of the debris field, a task made easier this time because Khonsu had been so much closer than Pytheas. They identified three fragments with enough mass and relative momentum to seriously damage Dragon’s hull if they struck.

  An alliance of cells submitted a proposition:

  A sharp spike of excitement from Clemantine. When she’d suggested using the gun before, distance and the chaotic movement of the debris had made it impractical. Now, the situation was different.

  She pointed this out, in a bitterly ironic voice: *The philosopher cells have experience enough to know their range—and they’re confident.

  *Sooth, Urban agreed, too aware of the history of destruction contained within the memory of the cell field. *But it’s not without cost.

  He’d used the gamma-ray gun when he’d hijacked the ship, and twice more since then, but he did not like using it. *The gun pulls so much power, it weakens the propulsion reef and destabilizes the ship.

  He considered denying the philosopher cells the option of the gun. He had the ability to do that. Over the centuries he’d expanded and strengthened the branching structure of the bridge, increasing its links to the cell field so that he could overwhelm any debate among the philosopher cells and drive the discussion to the consensus he desired.

  But he already needed to replace two outriders. He did not want to risk the added burden of major damage to Dragon—and he could not predict the path of the debris because of the unknown effects of Khonsu’s shattered propulsion reef.

  *Let the cells have their way, he told Clemantine.

  *All right. Her tone grim, but eager. She wanted to see this, to experience it from the other side, from behind the gun this time. No longer helpless prey.

  They withheld input, let the cells find consensus on their own. It didn’t take long. The window of opportunity was limited. The cells had to act while the fragments retained heat and could be easily tracked.

  The gun was deployed. Its lens pivoted, lining up on the projected path of the tumbling debris. The reef blazed in Urban’s awareness. Power surged to the gun.
Once, twice, three times. Urban felt the force of it like a parallel universe punching through and twisting strands of space-time, destabilizing the internal structure of the ship.

  *By the Unknown God, Clemantine swore.

  The moment passed. The cells went quiet, waiting, watching.

  *I had no idea it’d be like that, she said. *It felt like . . . a chaos of tidal forces ripping open the ship.

  *I hate it, Urban admitted.

  *Sooth. I hope we never have to use it again.

  She stayed on the high bridge with him, waiting to see if the philosopher cells had hit their targets. Eventually, still riding the senses of the ship, Urban picked out three glowing vapor clouds.

  *There! he said. *It’s done.

  Chapter

  12

  Urban felt the future of his expedition to the Hallowed Vasties at risk. Not because he couldn’t replace two lost outriders. He’d done that before. He would do it again, in time. But because he would now have to reveal all the facts of Dragon’s history far sooner than he’d planned—and that could end the expedition.

  They were just a few years out from Deception Well and although it would take many more years to reverse momentum and return, they were still close enough to make it a real option. Once Clemantine learned what was to come she might demand to go back, and if she insisted, he would have to comply. No way would he ever force her to stay with him.

  He messaged everyone, while their ghosts were still active: *We need to talk about our future—and I don’t want to do this as ghosts in the library. Let’s all meet in the forest room, in one hour.

  He hoped the warmth, the reality, the subtle chemical interaction of living people would work to his benefit—and he wanted no interruptions from the Apparatchiks.

  Questions came back to him.

  His only answer was to repeat: *One hour.

  He woke his avatar from cold sleep, rising to consciousness amid the swaying ribbons of wall-weed in his chamber. Blinked his eyes and felt his gut knot in anxiety. Guilt was there too, though he tried to reject it. He hadn’t lied, exactly.