Riding the Crocodile

6

“Welcome to Trident. We’re honored by the presence of our most distinguished guest.”

Jasim stood beside the bed, waving a triangular flag. Red, green and blue in the corners merged to white in the center.

“How long have you been up?”

“About an hour,” he said. Leila frowned, and he added apologetically, “You were sleeping very deeply, I didn’t want to disturb you.”

“I should be the one giving the welcome,” she said. “You’re the one who might never have woken.”

The bedroom window looked out into a dazzling field of stars. It was not a view facing the bulge—by now Leila could recognize the distinctive spectra of the region’s stars with ease—but even these disk stars were so crisp and bright that this was like no sky she had ever seen.

“Have you been downstairs?” she said.

“Not yet. I wanted us to decide on that together.” The house had no physical wing here; the tiny observatory had no spare mass for such frivolities as embodying them, let alone constructing architectural follies in the middle of interstellar space. “Downstairs” would be nothing but a scape that they were free to design at will.

“Everything worked,” she said, not quite believing it.

Jasim spread his arms. “We’re here, aren’t we?”

They watched a reconstruction of the first two modules coming together. The timing and the trajectories were as near to perfect as they could have hoped for, and the superconducting magnets had been constructed to a standard of purity and homogeneity that made the magnetic embrace look like an idealized simulation. By the time the two had locked together, the third module was just minutes away. Some untraceable discrepancy between reality and prediction in the transfer of momentum to radiation had the composite moving at a tiny angle away from its expected course, but when it met the third module the magnetic fields still meshed in a stable configuration, and there was energy to spare to nudge the final assembly precisely into step with the predicted swinging of the Aloof’s beam.

The Amalgam had lived up to its promise: three worlds full of beings they had never met, who owed them nothing, who did not even share their molecular ancestry, had each diverted enough energy to light up all their cities for a decade, and followed the instructions of strangers down to the atom, down to the nanosecond, in order to make this work.

What happened now was entirely in the hands of the Aloof.

Trident had been functioning for about a month before its designers had arrived to take up occupancy. So far, it had not yet observed any gamma ray signals spilling out of the bulge. The particular pulse that Leila and Jasim had seen triggering fluorescence would be long gone, of course, but the usefulness of their present location was predicated on three assumptions: the Aloof would use the same route for many other bursts of data; some of the radiation carrying that data would slip past the intended receiver; and the two nodes of the network would have continued in free fall long enough for the spilt data to be arriving here still, along the same predictable path.

Without those three extra components, delivered by their least reliable partners, Trident would be worthless.

“Downstairs,” Leila said. “Maybe a kind of porch with glass walls?”

“Sounds fine to me.”

She conjured up a plan of the house and sketched some ideas, then they went down to try them out at full scale.

They had been into orbit around Najib, and they had traveled embodied to its three beautiful, barren sibling worlds, but they had never been in interstellar space before. Or at least, they had never been conscious of it.

They were still not truly embodied, but you didn’t need flesh and blood to feel the vacuum around you; to be awake and plugged in to an honest depiction of your surroundings was enough. The nearest of Trident’s contributor worlds was six hundred light-years away. The distance to Najib was unthinkable. Leila paced around the porch, looking out at the stars, vertiginous in her virtual body, unsteady in the phony gravity.

It had been twenty-eight thousand years since they’d left Najib. All her children and grandchildren had almost certainly chosen death, long ago. No messages had been sent after them to Nazdeek; Leila had asked for that silence, fearing that it would be unbearably painful to hear news, day after day, to which she could give no meaningful reply, about events in which she could never participate. Now she regretted that. She wanted to read the lives of her grandchildren, as she might the biography of an ancestor. She wanted to know how things had ended up, like the time traveler she was.

A second month of observation passed, with nothing. A data feed reaching them from Nazdeek was equally silent. For any new hint of the beam’s location to reach Nazdeek, and then the report of that to reach Trident, would take thousands of years longer than the direct passage of the beam itself, so if Nazdeek saw evidence that the beam was “still” on course, that would be old news about a pulse they had not been here to intercept. However, if Nazdeek reported that the beam had shifted, at least that would put them out of their misery immediately, and tell them that Trident had been built too late.

Jasim made a vegetable garden on the porch and grew exotic food in the starlight. Leila played along, and ate beside him; it was a harmless game. They could have painted anything at all around the house: any planet they’d visited, drawn from their memories, any imaginary world. If this small pretense was enough to keep them sane and anchored to reality, so be it.

Now and then, Leila felt the strangest of the many pangs of isolation Trident induced: here, the knowledge of the galaxy was no longer at her fingertips. Their descriptions as travelers had encoded their vast personal memories, declarative and episodic, and their luggage had included prodigious libraries, but she was used to having so much more. Every civilized planet held a storehouse of information that was simply too bulky to fit into Trident, along with a constant feed of exabytes of news flooding in from other worlds. Wherever you were in the galaxy, some news was old news, some cherished theories long discredited, some facts hopelessly out of date. Here, though, Leila knew, there were billions of rigorously established truths—the results of hundreds of millennia of thought, experiment and observation—that had slipped out of her reach. Questions that any other child of the Amalgam could expect to have answered instantly would take twelve hundred years to receive a reply.

No such questions actually came into her mind, but there were still moments when the mere fact of it was enough to make her feel unbearably rootless, cut adrift not only from her past and her people, but from civilization itself.

Trident shouted: “Data!”

Leila was halfway through recording a postcard to the Nazdeek Snakes. Jasim was on the porch watering his plants. Leila turned to see him walking through the wall, commanding the bricks to part like a gauze curtain.

They stood side by side, watching the analysis emerge.

A pulse of gamma rays of the expected frequency, from precisely the right location, had just washed over Trident. The beam was greatly attenuated by distance, not to mention having had most of its energy intercepted by its rightful owner, but more than enough had slipped past and reached them for Trident to make sense of the nature of the pulse.

It was, unmistakably, modulated with information. There were precisely repeated phase shifts in the radiation that were unimaginable in any natural gamma ray source, and which would have been pointless in any artificial beam produced for any purpose besides communication.

The pulse had been three seconds long, carrying about ten-to-the-twenty-fourth bits of data. The bulk of this appeared to be random, but that did not rule out meaningful content, it simply implied efficient encryption. The Amalgam’s network sent encrypted data via robust classical channels like this, while sending the keys needed to decode it by a second, quantum channel. Leila had never expected to get hold of unencrypted data, laying bare the secrets of the Aloof in an instant. To have clear evidence that someone in the bulge was talking to someone else, and to have pinned down part of the pathway connecting them, was vindication enough.

There was more, though. Between the messages themselves, Trident had identified brief, orderly, unencrypted sequences. Everything was guesswork to a degree, but with such a huge slab of data statistical measures were powerful indicators. Part of the data looked like routing information, addresses for the messages as they were carried through the network. Another part looked like information about the nodes’ current and future trajectories. If Trident really had cracked that, they could work out where to position its successor. In fact, if they placed the successor close enough to the bulge, they could probably keep that one observatory constantly inside the spill from the beam.

Jasim couldn’t resist playing devil’s advocate. “You know, this could just be one part of whatever throws the probes back in our faces, talking to another part. The Aloof themselves could still be dead, while their security system keeps humming with paranoid gossip.”

Leila said blithely, “Hypothesize away. I’m not taking the bait.”

She turned to embrace him, and they kissed. She said, “I’ve forgotten how to celebrate. What happens now?”

He moved his fingertips gently along her arm. Leila opened up the scape, creating a fourth spatial dimension. She took his hand, kissed it, and placed it against her beating heart. Their bodies reconfigured, nerve endings crowding every surface, inside and out.

Jasim climbed inside her, and she inside him, the topology of the scape changing to wrap them together in a mutual embrace. Everything vanished from their lives but pleasure, triumph and each other’s presence, as close as it could ever be.