Permutation City

He couldn't remember beginning the descent, although he understood clearly -- cloud-knowledge, cloud-memories -- the sense in which there was a beginning, and the sense in which there was none. His memories of the skyscraper, like his view of it, seemed to converge toward a vanishing point; looking back from the present moment, all he could recall was the act of descending, punctuated by rest. And although his mind had wandered, he'd never lost consciousness; his past seemed to stretch back seamlessly, forever -- yet he could hold it all in his finite gaze, thanks to some law of mental perspective, some calculus of memory limiting the sum of ever diminishing contributions to his state of mind from ever more distant moments in the past. But he had his cloud-memories, too; memories from before the descent. He couldn't join them to the present, but they existed nonetheless, a backdrop informing everything else. He knew exactly who he'd been, and what he'd done, in that time before the time he now inhabited.

Peer had been exhausted when he'd stopped, but after a minute's rest he felt, literally, as energetic and enthusiastic as ever. Back in cloud-time, preparing himself, he'd edited out any need or desire for food, drink, sleep, sex, companionship, or even a change of scenery, and he'd preprogrammed his exoself -- the sophisticated, but nonconscious, supervisory software which could reach into the model of his brain and body and fine-tune any part of it as required -- to ensure that these conditions remained true. He resumed the descent gladly, a happy Sisyphus. Making his way down the smooth mirrored face of the skyscraper was, still, the purest joy he could imagine: the warmth of the sun reflecting back on him, the sharp cool gusts of wind, the faint creak of steel and concrete. Adrenaline and tranquility. The cycle of exertion and perfect recovery. Perpetual motion. Touching infinity.

The building, the Earth, the sky, and his body vanished. Stripped down to vision and hearing, Peer found himself observing his Bunker: a cluster of display screens floating in a black void. Kate was on one screen; two-dimensional, black-and-white, nothing but her lips moving.

She said, "You set your threshold pretty damn high. You'd be hearing about this a decade later if I hadn't called you in."

Peer grunted -- disconcerted for a moment by the lack of tactile feedback from the conventional organs of speech -- and glanced, by way of eye-movement-intention, at the screen beside her, a graph of the recent history of Bunker time versus realtime.

Observing the Bunker -- "being in it" would have been an overstatement -- was the most computing-efficient state a Copy could adopt, short of losing consciousness. Peer's body was no longer being simulated at all; the essential parts of his model-of-a-brain had been mapped into an abstract neural network, a collection of idealized digital gates with no pretensions to physiological verisimilitude. He didn't enter this state very often, but Bunker time was still a useful standard as a basis for comparisons. At best -- on the rare occasions when demand slackened, and he shared a processor cluster with only two or three other users -- his Bunker-time slowdown factor dropped to about thirty. At worst? Up until a few minutes ago, the worst had been happening: a section of the graph was perfectly flat. For more than ten hours of real time, he hadn't been computed at all.

Kate said, "Operation Butterfly. Weather control simulations. The fuckers bought up everything."

She sounded shaken and angry. Peer said calmly, "No great loss. Solipsist Nation means making your own world, on your own terms. Whatever the risks. Real time doesn't matter. Let them give us one computation per year. What would it change? Nothing." He glanced at another display, and realized that he'd only been in the skyscraper model for seven subjective minutes. The false memories had meshed perfectly; he would never have believed it had been so short a time. Pre-computing the memories had taken time, of course -- but far less than it would have taken to accumulate the same effect by conventional experience.

Kate said, "You're wrong. You don't --"

"Let them run one moment of model time for one Copy on every processor cluster, the day it's commissioned -- and then dedicate it entirely to other users. Each Copy would thread its way from machine to machine, with a slowdown of a few billion . . . and it wouldn't matter. The manufacturers could run us all for free -- turn it into a kind of ritual, a blessing of the hardware by the spirits of the dead. Then we could abolish all the trust funds, and stop worrying about money altogether. The cheaper we are, the less vulnerable we are."

"That's only half the truth. The more we're marginalized, the more we're at risk."

Peer tried to sigh; the sound that emerged was plausible enough, but the lack of sensation was annoying.