Permutation City

30

The leaders of the Contact Group assembled in Maria’s apartment. They’d barely taken their seats when Durham said, “I think we should move to my territory before we proceed any further. I’m on the far side of the hub from the Autoverse region—for what that’s worth. If distance still means anything, we should at least try to run our models somewhere reliable.”

Maria felt sick. The City itself was right beside the Autoverse: the fairground on the edge of the desert. But no Elysians were being computed in that public space; only buildings and puppet pedestrians. She said, “Six other founders have pyramids adjoining the Autoverse. If you think there’s a chance that effects are spilling over the border… can’t you find a pretext to get them to move their people as far away as possible? You don’t have to spell things out—you don’t have to tell them anything that might increase the danger.” Durham said wearily, “I’ve had enough trouble persuading thirty-seven dedicated Autoverse scholars to occupy themselves with projects which will keep them out of our way. If I started suggesting to Elaine Sanderson, Angelo Repetto and Tetsuo Tsukamoto that they rearrange the geometry of their computing resources, it would take them about ten seconds to put the entire Autoverse under scrutiny, to try to find out what’s going on. And the other three pyramids are occupied by hermits who haven’t shown themselves since the launch; we couldn’t warn them even if we wanted to. The best thing we can do is deal with the problem as quickly—and inconspicuously—as possible.”

Maria glanced at Dominic Repetto, but apparently he was resigned to the need to keep his family in the dark. She said, “It makes me feel like a coward. Fleeing to the opposite side of the universe, while we poke the hornet’s nest by remote control.”

Repetto said drily, “Don’t worry; for all we know, the TVC geometry might be irrelevant. The logical connection between us and the Autoverse might put us at more risk than the closet physical neighbors.”

Maria still chose to do everything manually, via her “solid” terminal; no interface windows floating in midair, no telepathic links to her exoself. Zemansky showed her how to run the obscure utility program which would transport her right out of her own territory. The less wealthy Copies back on Earth had darted from continent to continent in search of the cheapest QIPS—but in Elysium there would never have been a reason for anyone to shift this way, before. As she okayed the last query on the terminal, she pictured her model being halted, taken apart and piped through the hub into Durham’s pyramid—no doubt with a billion careful verification steps along the way… but it was impossible to know what even the most stringent error-checking procedures were worth, now that the deepest rules upon which they relied had been called into question.

As a final touch, Durham cloned the apartment, and they moved—imperceptibly—to the duplicated version. Maria glanced out the window. “Did you copy the whole City as well?”

“No. That’s the original you’re looking at; I’ve patched in a genuine view.”

Zemansky created a series of interface windows on the livingroom wall; one showed the region running the Autoverse, with the triangular face which bordered Maria’s own pyramid seen head-on. On top of the software map—the midnight-blue of the Autoverse cellular automation program, finely veined with silver spy software—she overlayed a schematic of the Lambertian planetary system, the orbits weirdly chopped up and rearranged to fit into the five adjacent pyramids. The space being modeled was—on its own terms—a relatively thin disk, only a few hundred thousand kilometers thick, but stretching about fifty per cent beyond the orbit of the outermost planet. Most of it was empty—or filled with nothing but light streaming out from the sun—but there were no short-cuts taken; every cubic kilometer, however featureless, was being modeled right down to the level of Autoverse cells. The profligacy of it was breathtaking; Maria could barely look at the map without trying to think of techniques to approximate the computations going on in all the near-vacuum. When she forced herself to stop and accept the thing as it was, she realized that she’d never fully grasped the scale of Elysium before. She’d toured the Lambertian biosphere from the planetary level right down to the molecular—but that was nothing compared to a solar- system’s-worth of subatomic calculations.

Durham touched her elbow. “I’m going to need your authorization.” She went with him to the terminal he’d created for himself in a corner of the room, and typed out the code number which had been embedded in her scan file back on Earth; the ninety-nine digits flowed from her fingers effortlessly, as if she’d rehearsed the sequence a thousand times. The code which would have granted her access to her deceased estate, on Earth, here unlocked the processors of her pyramid.

She said, “I really am your accomplice, now. Who goes to prison when you commit a crime using my ID?”

“We don’t have prisons.”

“So what exactly will the other Elysians do to us, when they find out what we’ve done?”

“Express appropriate gratitude.”

Zemansky zoomed in on the map to show the individual TVC processors along the border, and then enlarged the view still further to reveal their elaborate structure. It looked like a false-color schematic of an array of three- dimensional microcircuits—but it was too rectilinear, too perfect, to be a micrograph of any real object. The map was largely conjecture, now: a simulation guided by limited data flowing in from the grid itself. There were good reasons why it “should have been” correct, but there could be no watertight evidence that anything they were seeing was actually there.

Zemansky manipulated the view until they were peering straight down the middle of the thin layer of transparent “null” cells which separated the Autoverse region from Maria’s territory—bringing her own processors into sight for the first time. An arrow in a small key diagram above showed the orientation; they were looking straight toward the distant hub. All the processors were structurally identical, but those in the Autoverse were alive with the coded streams of activated states marking data flows, while her own were almost idle. Then Durham plugged her territory into the software he was running, and a wave of data swept out from the hub—looking like something from the stargate sequence in 2001—as the processors were reprogrammed. The real wave would have passed in a Standard Time picosecond; the map was smart enough to show the event in slow motion.

The reprogrammed processors flickered with data—and then began to sprout construction wires. Every processor in the TVC grid was a von Neumann machine as well as a Turing machine—a universal constructor as well as a universal computer. The only construction task they’d performed in the past had been a one-off act of self- replication, but they still retained the potential to build anything at all, given the appropriate blueprint.

The construction wires reached across the gap and touched the surface of the Autoverse processors. Maria held her breath, almost expecting to see a defensive reaction, a counterattack. Durham had analyzed the possibilities in advance: if the TVC rules continued to hold true, any “war” between these machines would soon reach a perpetual stalemate; they could face each other forever, annihilating each other’s “weapons” as fast as they grew, and no strategy could ever break the deadlock.

If the TVC rules failed, though, there was no way of predicting the outcome.

There was no—detectable—counterattack. The construction wires withdrew, leaving behind data links bridging the gap between the pyramids. Since the map was showing the links as intact, the software must have received some evidence that they were actually working: the Autoverse processors were at least reacting as they should to simple tests of the integrity of the connections.

Durham said, “Well, that’s something. They haven’t managed to shut us out completely.”

Repetto grimaced. “You make it sound like the Lambertians have taken control of the processors—that they’re deciding what’s going on here. They don’t even know that this level exists.”

Durham kept his eyes on the screen. “Of course they don’t. But it still feels like we’re sneaking up on some kind of… sentient adversary. The Lambertians’ guardian angels: aware of all the levels—but jealously defending their own people’s version of reality.” He caught Maria’s worried glance, and smiled. “Only joking.”

Maria looked on as Durham and Zemansky ran a series of tests to verify that they really had plugged in to the Autoverse region. Everything checked out—but then, all the same tests had worked when run through the authorized link, down at the hub. The suspect processors were merely acting as messengers, passing data around in a giant loop which confirmed that they could still talk to each other—that the basic structure of the grid hadn’t