“I don’t understand,” Nis said.
“I understand,” said Haf. “We should do as Tio said.”
“What?” Roi was confused now. “What did Tio say?” Tio was a friend of Haf’s who had wandered from teacher to teacher among the theorists, learning a great deal but then arguing with everyone, refusing to perform the calculations they expected of him.
“I told you thirty-six shifts ago,” Haf said reprovingly. “He treats space-time as lots of small, flat pieces. When you make them small, the templates describe what happens at the corners, how you join the pieces together. But the templates are easy, not like these weeds.” He shook the frame of Roi’s that he’d been checking.
“You just need a lot of them,” Roi said. For a few heartbeats she was simply dazed, unsure if this was some false promise that her weariness had caused her to misjudge. But Haf’s words made perfect sense; Tio’s idea was the only way forward.
She asked Haf, “Can you find him? Can you bring him here?”
“Sure.” Haf prodded Pel and they left the chamber together.
Nis said, “I still don’t see it.”
“Wait for Tio,” Roi suggested. “If I try to explain it, the way I’m feeling right now I’ll probably just end up confusing us both.”
“But who does he work with? What’s he been doing?”
“He’s been working by himself,” she said.
“A team of one?” Nis scoffed.
“Zak was a team of one,” Roi said. “A long time ago.”
Nis was unimpressed by the comparison. “Not everyone who thinks they’re like Zak is actually correct in that perception.”
“That’s true,” Roi conceded. “So let’s just judge his ideas on their merits.”
Haf and Pel returned with Tio. For a moment he seemed nervous and resentful, but when Roi addressed him respectfully and said that she needed his help, his posture softened and the words spilled out of him.
He had reformulated Zak’s principle, he explained, in a way that suited a picture of space-time built up from many small, flat pieces. The result was not perfect, like Tan’s geometry, which could be trusted down to the finest detail. But the calculations, though laborious and repetitive, were extremely simple. You couldn’t fail to find an answer.
Roi asked, “How many divisions would we need to make, how many pieces of space-time to cover everything from our last known orbit to the Wanderer’s, and a short way beyond?”
Tio fell silent, calculating something, or guessing. “Perhaps six to the eighth pieces. Six to the ninth for more accuracy.”
“And what kind of team would we need? To calculate all the geometry before we reach the Wanderer’s orbit?”
Tio said, “Six to the fourth, if they’re good calculators. Maybe double that if everyone needs checkers.”
Six to the fourth. Ruz’s void-watchers, and all the theorists combined, would come to less than a quarter of that. Sen’s team could not leave their work, but perhaps some of Jos’s light-messengers could be diverted for a while; with no observations to bring in fresh information, there was little news to be relayed.
“Can you set up this problem in a simple way, that everyone will be able to understand?”
“Yes,” Tio replied confidently.
“So that anyone who can manage arithmetic can learn what to do in half a shift?” Roi pressed him.
Tio said, “I’m sure of it.”
Roi looked around the small chamber, trying to picture a much larger one nearby where they could put everyone. She noticed, distractedly, that Pel was now carrying four seed packages inside her, and that Haf’s body was empty. He’d shown no signs of pain; Pel had taken the packages pre-emptively, without even needing to witness her friend’s suffering.
Everything in the world was strange, but Roi didn’t care. The last thing that was in their power to change had finally shown signs of yielding. She believed they would survive now.
Tan was staying in a small chamber, not far from Tio’s geometry-calculators. Before starting her shift Roi brought him food, and they spoke for a while.
“Where are we now?” he asked.
“All the measurements put our orbit close to size twenty.”
“Twenty!” Tan marveled. “No wonder I feel like I’m back in the Null Chamber.”
“The weights are nothing,” Roi agreed. “Even at the garm edge now, people can cling to the ceiling for a whole shift if they want to.”
“I don’t want to cling to the ceiling,” Tan said. “I just want to live a few more shifts. I want to see this through.”
“I understand.” Roi had never asked him about his children, whether he caught himself hunting for them in the crowds. Everyone’s gaze had shifted, though, whether it was focused on their own hatchlings or just the generation as a whole.
“Either that, or we’ll all go out like Zak did,” Tan chirped, making a joke of it.
“We’ve worked hard,” Roi said. “There’ll be ease and safety for the next generation.”
“Let them have safety,” Tan said, “but not ease.”
“Why?”
“Do you want them to go back to the old ways?” Tan looked at her searchingly. “You do know that’s what will happen, don’t you? If they have nothing to push against, nothing to understand, nothing to explore.”
Roi didn’t know how to answer him. She knew, now, that she could never go back herself, but she wouldn’t have to face that; she would not live a great deal longer than Tan. Did it matter, though, if Haf and Pel and Tio slipped gradually from their adventurous youth into a world where the generation that followed would once more live for nothing but the buzz of cooperation, whatever the team, whatever the task?
“Do I have any say in it?” she replied. “Is there anything I can do that will determine how much they’ll struggle?”
Tan said, “Nothing at all. But you can still hope for the right thing.”
Roi left him to start her shift, entering quietly and taking her place in the chamber from Leh; the two of them shared a position, working alternate shifts. Tio had arranged the geometry-calculators in a carefully designed pattern, so that each one exchanged information with just five of their neighbors. There was no need for messengers to weave back and forth between them; the results each person needed in order to continue always came from someone beside them.
Numbers washed back and forth across the chamber, but Roi could stay focused on her own simple tasks, ignoring the wider picture. Compared to battling the templates for a space-time connection, it was almost as mindless as weeding a crop. She let herself fall into a happy daze, thinking of nothing but the details of each calculation.
Halfway through the shift, she emerged from her trance; Tio had called a halt. A dozen people walked across the chamber, moving from calculator to calculator, asking them about the numbers associated with the piece of space-time they had just analyzed. The answer they were given decided which of the calculator’s neighbors to move on to. In effect, Tio’s path-walkers were letting an imaginary object fall in a straight line across each small region of space-time being modeled, and seeing where it emerged. By keeping track of a few simple details, they could follow it into the future—across a region that was effectively curved by the way the many flat pieces were joined—building up a fair approximation to a natural path.
The orbit of the Splinter. The orbit of the Wanderer. The light and flares that might pass between them.
Kem and Nis studied the results, and shaped them into instructions for Sen. The changes made in the tunnels, ever finer now, steered the Splinter closer to their best guess for the safest possible place to be.
When her shift was over, Roi went to see Kem and Nis.
“Where are we?” Roi asked. It was a question that no one could stop asking.