Incandescence

I can't do this, she pleaded, though she didn't know what she was addressing. Something broke, something weakened, and there was distance between her and the brightness. Finally. She relaxed. This was death: like sleep.

The pain welled up again, but the darkness remained. She thought she slept, three or four times, but there was no waking into light, either savage or gentle. Only waking into pain.

Roi flexed her legs, and felt her claws scrabble against rock. It hurt her to move, but it was not impossible. The only thing impossible was vision.

She waited, and heard movement around her, then plaintive drumming. She was blind, but she was alive, and others had survived alongside her.

There was work to do; she had to learn everything about the new situation. She called out to her team-mates, "Can someone tell me if the light is gone?"

Haf said, "I have some interesting news."

Roi put down her template frame.

"There's rock in our orbit," he announced. "I think we should stay here, or at least close by."

"Rock? What do you mean?"

"The void-watchers can see it with their light-gatherers. Pieces of rock, orbiting the Hub."

"You mean. other Splinters?"

Haf hesitated. "I don't think so. The shape's not the same. And the rock isn't exactly like our rock."

Roi let the puzzling news sink in. No mythical cousins, but that had always been a fanciful notion. To have rock, or something like it, not far away might be useful. She had no idea how they would reach it, but she was sure Haf would find a way eventually.

The death of the Wanderer had replenished the Incandescence, thickening it to the point that they were threatened not with famine but corrosion from the wind. They had reopened the tunnels and started moving out again, searching for the right balance. They had reached a point where the wind was not too strong but the crops would still be plentiful, and now they had this unexpected boon.

"I agree," she said. "We should stay here."

The Wanderer had killed a third of their people, and blinded another third. Bard, Cho, Ruz, Nis, Tio and Jos were all gone. Nobody understood what had happened, what had given the Wanderer's disintegration such force. Perhaps in a dozen generations someone would find a way to explore such mysteries; there might yet be something simple beneath it all.

Haf mused, "Rock's a good start, but I really don't think it will do for the wall."

"What wall?" Roi knew exactly what he was talking about, but she enjoyed teasing him.

Haf rasped annoyance. "The Hub is a dangerous place. Once we've left it behind, nobody should get close to it ever again. If they come this way we should send them back, the way you guide a hatchling away from danger: just pick them up and turn them around."

Roi chirped with delight. "First a wall, and now. what? A great machine for herding hatchlings who are hurtling through the void! Do you know how many spans it is around the Hub? In thirty-six times thirty-six generations, we could never build anything that began to do what you describe."

"Perhaps you're right," he conceded, but he didn't sound the least bit sincere.

She heard him approach and pick up one of her frames.

"Can I check your calculations?" he asked.

"That would be good."

The Wanderer's death-throes had given their orbit some elevation again: a return to light and dark, she'd been told, and a chance to see out into the void once more. She had been calculating a manoeuvre that she hoped they could perform with the tunnels to maintain the tilted orbit indefinitely. The opportunity to look out at their surroundings was too precious to lose again.

Haf worked in silence. Roi listened to the clicking of his claws against the stones, and felt herself drifting into sleep.

Afterword

The "weight and motion" of objects in the Splinter follow from Einstein's theory of general relativity; many of the effects described also occur in Newtonian gravity, but observations within the Splinter are sufficient to discriminate between the two theories. The best general reference on this subject is:

Gravitation by C. W. Misner, K. S. Thorne and J. A. Wheeler,

W. H. Freeman, New York, 1970.

The most comprehensive treatment of the particular space-time geometries discovered by the protagonists is:

The Mathematical Theory of Black Holes by S. Chandrasekhar,

Oxford University Press, Oxford, 1992.

"Zak's principle" is essentially Einstein's equation in a vacuum, that is, the version that applies when the matter in your immediate vicinity has no significant gravitational effect. The general equation, which allows for the presence of matter, is described in terms that are almost as simple in this excellent account:

"The Meaning of Einstein's Equation" by John C. Baez and

Emory F. Bunn,