“Two days ago I deployed particle detectors astern,” it said (although “astern,” it felt bound to warn her, was an almost meaningless direction in terms of the geometries involved), “and began counting significant quantum events. This is the result.”

“Two days ago?”

“Stochastic resonance takes time.”

Seria Mau had the data piped into her tank in the form of a signature diagram and studied them. What she saw was limited by the White Cat’s ability to represent ten spatial dimensions as four: an irradiated-looking grey space, near the centre of which you could see, knotted together, some worms of spectral yellow light, constantly shifting, pulsing, bifurcating and changing colour. Various grids could be laid over this model, to represent different regimes and analyses.

“What is it?” she said.

“I think it’s a ship.”

Seria Mau studied the image again. She ran comparison studies. “It isn’t any kind of ship I know. Is it old? What is it doing out there?”

“I can’t answer that.”

“Why?”

“I’m not yet entirely certain where ‘ out there’ is.”

“Spare me,” said Seria Mau. “Do you know anything useful at all?”

“It’s keeping pace with us.”

Seria Mau stared at the trace. “That’s impossible,” she said. “It’s nothing like a K-ship. What shall we do?”

“Keep sorting quanta,” said the mathematics.

Seria Mau opened a line to the human quarters of the ship.

There, one of the men had launched a holographic display and was clearly making some kind of presentation to the rest of them, while the female clone sat in a corner painting her fingernails, laughing with a kind of weak maliciousness at everything he said, and making inappropriate comments.

“What I don’t understand,” she said, “is why she never has to do that. I have to do it.”

The display was like a big smoky cube, showing fly-by images from the Radio Bay cluster, which contained among others Suntory IV and 3-alpha-Ferris VII. Low-temperature gas clouds roiled and swirled, failed old brown dwarf stars blinking through them like drunks crossing a highway in fog. A planet jumped into resolution, mushroom-coloured, with creamy sulphurous-looking bands. Then there were images from the surface: clouds, chaotic streaming rain, less weather than chemistry. A scatter of non-human buildings abandoned two hundred thousand years before: something that looked like a maze. They often left mazes. “What we’ve got here is old,” the man concluded. “It could be really old.” Suddenly the camera jumped to an asteroid in full view of the Tract, which blazed out of the display like costume jewellery on black velvet.

“I think we’ll leave that for a later trip,” he said.

Everyone laughed except the clone, who spread her hands in front of her. “Why do you all hate me so,” she said, looking at him over her bright red nails, “that you make me do it and not her?”