"To everyone who was alive whenever exactly it happened. Every thing that was alive. Every animal and plant on the planet. And every inanimate thing as well-every grain of sand on every beach, every blade of gra.s.s, every drop of water in every ocean, every molecule of oxygen in the atmosphere, every atom in every rock, all the way to the Earth's core."

"So what was this incredible thing that happened?"

"It was like a photograph," she said. "Like the instant when the flash goes off and the image is burnt on to the plate. Except it wasn't a simple picture. It was a three-dimensional one, an image of astonishing, mind-blowing complexity. A photograph of the entire planet, down to the quantum horizon of information capture. Maybe even beyond Heisenberg...who knows? Our physics doesn't even hint at how they did it. We call it a quantum snapshot, but that doesn't mean we have clue one about what was involved in producing it. That's just a name we give it to hide our ignorance."

"But no one could have done such a thing," Floyd said. "We'd have heard about it. It would have been all over the headlines."

"It wasn't done by any agency on Earth. The snapshot was taken by an external power. Beings from another planet, or another dimension, or another time. We have no idea what they were like or what motivated them to do this. Only that it happened."

"Martians, again?"

"Not Martians. Probably not even anything we'd recognise as an intelligent ent.i.ty. They must have been far ahead of us, Floyd. About as far ahead of us as we're ahead of sponges, or beetles. G.o.dlike, in every sense."

"And they came along and took this photograph-"

"The snapshot. Like I said, we don't know how. Maybe they built a structure around the entire planet, in a matter of hours. A clever, subtle structure, which was somehow able to make the recording in an eyeblink without anyone noticing-and, more importantly, without significantly affecting the planet itself in any way. Or maybe they just kissed something against the planet, another object that became entangled with the quantum ident.i.ty of the Earth, encoding all that information into itself, ready to be deciphered again in the future. We could speculate about the 'how' for ever and never get close to the truth. What we can guess at more successfully, perhaps, is the 'why.' We think their motives were fundamentally benign. They were interested in preservation, in creating a record of the Earth that could be used to recreate the planet in the event of a future catastrophe. We call that the 'backup copy' theory. According to that view, the ent.i.ties that did this are like cosmic archivists, or system administrators. They go around the galaxy, visiting worlds that are at a sensitive stage of evolution, and they make copies using the quantum-snapshot process."

"And what happens to these 'copies?'" Floyd asked.

"That's the big question. Our best guess-and there is some intelligence to support this-is that the copies are dispersed throughout the galaxy, preserved in a kind of storage media. Think of these storage media as safety-deposit boxes, each of which contains a single photograph. One might be the image of Earth at a particular moment in the late nineteen thirties. Another might contain a snapshot of Earth from sixty-five million years ago, or the ancient history of another planet entirely. We think we've found some of these boxes. We call them anomalous large structures, or ALS spheres. They're stellar-sized objects of obvious alien origin: huge armoured spheres vast enough to contain entire planets and a sizeable volume of s.p.a.ce around them."

"Have you looked inside any of these boxes?"

"The best anyone has been able to do was take a fuzzy image of the contents of one sphere. Embedded inside, coincidental with the geometric centre, was a dense object with just the kind of neutrino-absorption cross section that you'd expect from a rocky world. It wasn't any planet we recognised, based on its implied density and size."

Floyd risked a contribution. "A snapshot of another world?"

"Yes. Frozen inside the structure like a perfect three-dimensional photograph. Of course, if we scoured the galaxy thoroughly enough, we'd eventually find the original-the world from which the copy was made. a.s.suming we were able to recognise it when we found it."

"Tell me how all this fits together. Why would anyone want to make copies of planets and put them inside giant eggsh.e.l.ls? And what the h.e.l.l does it have to do with me?"

"Haven't you figured it out yet?" she said, with a snarl of irritation. "Floyd was copied: him and every living person on the planet. After the snapshot was taken, he went on to live whatever life it was he lived. History rolled on and the world ended in twenty seventy-seven. And that should have been the end of it. But now Floyd's copy has come back to life somehow, hundreds of years later, and I'm talking to it at this exact moment, trying to explain to it why it isn't who it thinks it is." She said each and every "it" with deliberate, wounding emphasis.

"I can't be a copy," Floyd said. "I remember everything. I remember what I did when I was a kid and everything I did afterwards, until now."

"That doesn't prove anything. You were copied with all of Floyd's memories intact, down to the last detail."

"Wait a minute. If the copy was made a few hundred years ago, why isn't the copy dead by now?"

"You should be dead," Auger said. "And you would be, if the copy had been allowed to live immediately after the snapshot was produced. But it wasn't. The copy-the complete three-dimensional image of the Earth and its inhabitants-appears to have remained frozen until about twenty-three years ago, held in some kind of suspended quantum state." Floyd saw her close her eyes, as she groped for a simile. "Like an undeveloped photograph," she offered.

"But someone came along and developed it."

"Yes. Quantum states like that are very fragile, and a copy of an entire planet must be astonishingly fragile: a house of cards just waiting to collapse at the merest sneeze. But somehow whoever created it was able to isolate it to a sufficient degree to preserve it for a while. The weak radiation signals that came through the sh.e.l.l-the gravitational and neutrino emissions-obviously weren't enough to upset the stasis, or whatever you want to call it. But still there was some kind of trigger. By your calendar it was nineteen fifty-nine when we met, agreed?"

"Yes."

"We also know-from studying historical events in your timeline-that your world was on more or less the right track until at least the mid-thirties. By the end of nineteen forty it had changed-the German invasion in May of that year failed-which implies a build-up of small events over a period of years that eventually had a significant impact. Most likely, the snapshot took place somewhere around nineteen thirty-six, twenty-three years ago as far as you're concerned."

"If you say so," Floyd said grudgingly, conceding nothing.

"Now look at the same span of time in our chronology. We know that time pa.s.ses at the same rate in your world as it does in mine. It's twenty-two sixty-six now. Subtract twenty-three years and we're back in twenty-two forty-three, which is more or less when the Slashers had control of Mars and its moons, including Phobos."

"Where we're headed," Floyd added, if only to show that he was paying attention.

"Yes. And I can't believe that's a coincidence. My guess is that the snapshot began to evolve forward in time from the moment the Slashers opened the portal on Phobos. A little bit of the external universe must have begun to leak into the ALS, collapsing the image into a normal state of matter. The snapshot came alive."

In his mind's eye, Floyd had a sudden, horrible mental image. He pictured a kind of theatrical stage populated by stiff mechanical dancers, still as statues, coated in years' worth of dust. And then they began to move, slowly at first, ch.o.r.eographing their clockwork movements to music from a grindingly slow fairground organ. As the tortured, wheezing music gained speed, so did the dancers, whirling and gyrating in orbits and epicycles. He tried to shake the image, but the little figures danced on, gaining speed.

"But even if that were true," Floyd said, "even if I and everyone I know had been kept asleep for all those years-all those hundreds of years-shouldn't we remember it?"

"You wouldn't remember a d.a.m.ned thing," Auger said. "You skipped over three-hundred-odd years between heartbeats, Floyd-you and everyone else on the planet. Maybe you felt the tiniest moment of deja vu, or some other thing the French have a word for, but that would have been it."

"Everyone on the planet would have felt it?"

"Maybe. But how many of you would have even thought to remark on it?"

"You can't expect me just to accept this," he said.

"Floyd, I'm not asking you to accept anything." She sounded, for a moment, desperately sorry for him.

Hearing that in her voice only made him more afraid that she was, indeed, telling the truth and nothing

more.

"I'm not a copy of Wendell Floyd," he said, panic rising in his voice despite his attempts to keep it under control. "I am Wendell Floyd."

"You're a perfect copy. That's precisely how you would feel."

"Then what does that make me? Some kind of ghost, some kind of phoney imitation?"

"That's the way some people might see it."

"And is that the way you see it?"

"No," she said, after just too much hesitation. "Not at all."

"Now I know why you were so worried that I wouldn't be able to pa.s.s through that censor thing," Floyd

said.

"I couldn't know what would happen. No one had tried to bring anyone out of E2 before."

"It treated me like any other human being. Isn't that good enough for you?"

"Yes," she said. "I suppose it is. But listen to me, Floyd: you will never belong in my world. Your world

is back in Paris, as real or otherwise as it might be."

"Don't worry," he told her. "I have every intention of returning."

Something caught her eye again: some glint of meaning in the tumble of numbers racing across the

display screens. She flipped banks of switches, peered at the numbers again. Her face was a mask of

intense, troubled concentration.

"It's still getting closer?" Floyd asked.

"I'm worried about this. It almost looks as if..." But then she shook her head, as if trying to dislodge whatever upsetting thought had taken up residence. "It can't be."

"What can't be?"

"I might be making a mistake here," she said.

"I'll take the risk. What's got you so rattled?"

"I think what I'm seeing is the end of the tunnel behind us. It's acting like a reflecting surface, bouncing

signals back towards us."

"But we left Paris behind hours ago."

"I know. And I think something bad must have happened just as we left. The numbers make it look as if

the tunnel's collapsing, folding shut just behind us."

"Can that happen?"

"I guess so. Skellsgard always said there might be a problem if the throat contracted too quickly during

an insertion. It looks as if the robot couldn't handle the injection procedure. Or else it was programmed

to find the one solution that would get us out of Paris, even if that meant sacrificing the link, and

itself..."

"What does that mean?"

"It means we're sliding down a pipe that's getting shorter all the while, with the closed end catching up with us."

"That doesn't sound good to me."

"It doesn't sound good to me, either." Auger tapped a finger against another display. "But these numbers back me up. They show our speed through the hyperweb, with our estimated ETA at Phobos. We're picking up momentum, shaving hours off our projected journey time."

"Isn't that a good thing?"

"No. Because it's nothing that the transport is doing, and it can't be due to another ship or pile of debris behind us. It must be due to something pretty fundamental happening to the hyperweb. I think it's the field geometry in the walls, squeezing us forward like a pip. As the crimped end gets nearer and nearer, we're being pushed along faster and faster by the inclosing walls." She turned to Floyd. "But the ship

isn't built to handle speeds much faster than this. And I don't know what will happen when the curvature becomes really severe, and we end up squeezed into the end of the tunnel."

"Is there anything we can do about it?"

"Not much," Auger said. "I could fire the steering jets, try to push us away from whatever is following

us. But the jets aren't designed for sustained use. We'd buy a few minutes, maybe half an hour."