Incandescence

Jos seemed overwhelmed by the sudden turn of events. "I believe you when you say this is important," she said. "But my job here, with the rocks. I came here, I listened to Bard. " She trailed off, confused. The Jolt had changed her enough to bring her here, and enough to make her restless with ideas, but she hadn't entirely lost the sense that the best thing to do was to stick with your team as long as you could.

"When will it end?" she implored Roi. "I want the old way back."

"You'll get it back," Roi said. "But first you have to do this."

Jos signaled to her to halt, and they came to a stop together. With a rasp of reluctant acquiescence she eased the rock down between them.

Roi said, "You're just going to leave that here?"

"It's not my job any more," she replied.

Roi found Neth alone in a chamber, surrounded by template frames. Neth greeted her warmly, and listened to all the news.

"I'm sad to hear of Zak's death," Neth said, "but I expected it long ago."

Roi didn't want to dwell on that. "So how are you spending your time here?"

"I'm trying to understand the wind," Neth said. "Even before we've cut open the mouth of the tunnel, moving all this rock has changed the flow. This whole thing is not as simple as Bard suggests."

"What do you mean?"

"If the Splinter simply wasn't here, the wind would blow straight from rarb to sharq; we can all agree on that. I'm not convinced, though, that cutting a long tunnel through the Splinter will necessarily have the same effect. The surrounding rock will still be diverting and complicating the flow of the rest of the wind. It will all mix together in the tunnel. The result isn't easy to predict."

Roi was dismayed. She had thought the hard part would be persuading people to help build the tunnel; now Neth was suggesting that it might not even work.

"What can we do if the flow isn't strong enough to make a difference? Build more tunnels?"

"That could help," Neth said. "But the important thing will be learning how to shape and control the flow through however many tunnels we have. What you say Bard has planned, with the varying plugs, will make a good start, but we'll need to study the effects of that arrangement, experiment with it, fine-tune it."

"And make calculations?"

"Of course."

Roi struggled to reconcile herself to this new setback. She couldn't be sure that Neth was right, but she appeared to have thought about the problems of the flow more deeply than anyone else. Bard would certainly get the rock shifted and the machinery in place, but without Neth's aid, there was a chance it would all be in vain.

She could not ask Neth to leave and join her in the Null Chamber.

"Tell me," Roi said, "given what I saw in the void, how do you think we should approach the calculations now?"

For a few long heartbeats Roi was afraid that Neth was going to modestly demur that it was not her place to offer advice on the matter, now that she'd left the theorists' group. Not my job any more.

If that was her inclination, she managed to overcome it. "Try to hold on to as much symmetry as you can," she suggested. "You've shown that there isn't perfect symmetry around the Hub in all directions. But for all the time we sat in the plane of the Incandescence, nothing in the weights changed while the Splinter completed each orbit. In fact, the period of the orbit was impossible to discern without looking outside the Splinter. That tells us that the geometry as we moved around the Hub was completely unvarying."

"We were moving through just one plane, though," Roi said.

"Yes," Neth replied, "but the simplest way such a symmetry could arise would be if it held true for all planes parallel to the Incandescence. So if you rotate the whole geometry around an axis passing through the Hub, perpendicular to the plane of the Incandescence, it should be left unchanged. Instead of the symmetry of a sphere, look for the symmetry of an ellipsoid."

As Roi departed, she thought irritably: That's obvious. I didn't need Neth to tell me that.

Everything simple was obvious in retrospect, though. What remained to be seen was whether the void itself had any interest in the kind of simplicity that might let their minds reach out and grasp the truth about the world, or whether Zak's principle was just a beautiful, but misguided, statement of hope.

When Roi returned to the Null Chamber, she found to her delight that it was crawling with hatchlings. Gul was among them, orchestrating their exuberant play.

She climbed out along a wire to reach him.

"I heard the news about Zak," he said. "I thought you'd probably be too busy to come back to us for a while. Then I thought, why not let them experience weightlessness and see some experiments, instead of just hearing about everything second-hand?"