Dr. Ludwig said, “Five minutes exactly. Perfect displacement. Perfect visibility.”
“Paradox number one,” Dr. White chimed in. “The duplication. The overlap of identity.”
“And paradox number two, also. The cumulative and self-modifying aspects of the time-stream correction.”
“Say that again?” Eric asked.
Ludwig didn’t trouble to reply. He glowered and scowled and vanished into the flow of his own intricate thoughts. It seemed to bother him that Eric had spoken at all. As if Eric were nothing more than an irritating distraction at this very complicated moment.
All around the room, technicians were throwing switches and tapping commands into terminals. Everybody was tense. To all these people Time Zero, the moment of the initial shunt, was still four and a half minutes away. The final delicate calibrations and balances had to be made.
Some of the staff people were staring at him the way they might stare at a ghost. That puzzled him for a moment. They should be used to backward-going time travelers by now. After all, Sean had already come this way on the minus-fifty-minute shunt, hadn’t he? And Eric would be doing the minus-five-hundred-minute one himself a few hours ago. Even though he hadn’t experienced it yet, they had. Or should have.
But then Eric recalled what they had told him about these past-changing paradoxes. Each swing of the pendulum retroactively corrected everybody’s memories and perceptions. That was how it had been in the earlier experiments with robots and animals and they expected it to work the same this time. Nobody remembered Sean’s minus-fifty minutes appearance, or any of the earlier ones, because they hadn’t happened yet. But as the pendulum kept swinging, those appearances would happen, at times earlier than this, and the corrections would be made, and everyone would begin to remember a past that right now didn’t yet exist. Or something like that. It made no sense if you tried to think of it in the old straight-line way. Now that time travel was a fact, no one could think that way ever again.
Warning lights were lit up on all the instrument panels now. Critical displacement momentum was nearly attained. Sean and that other Eric would be on their way in another few instants. And he’d be moving along, too. He couldn’t stay here much longer. Any minute now the next Eric2 would be making the journey from Time Zero back to minus-five-minutes, the journey that he himself had just taken. The mathematics of time wouldn’t allow him still to be here when the loop began all over again. You could have an Eric and an Eric2 in the same place at the same time, but not more than one Eric2. He would have to be up and out, swinging toward his second stop, the plus-fifty-minute level.
He could feel the force pulling at him now.
Eric waved jauntily at the Eric and Sean on the platform. When shall we three meet again, he asked himself? Probably never. He’d see Sean again at the end of the experiment, sure. If all went well. But there was no reason why he should ever come face-to-face with himself a second time.
Which was just as well, he decided. There’s something creepy about looking yourself in the eye.
“Have a good trip, guys!” he called out to them. And the force seized him and swept him away into the time-stream.
2. Sean + 5 minutes
And then at long last they threw the final switch, the one that would send him spinning off into the vast distant reaches of time, and nothing happened. At least that was how it felt to Sean at first. No blinding flashes of light, no strangely glowing haloes, no sinister humming sounds, no sense of turbulent upheaval. Nothing. An odd calmness, even a numbness, seemed to envelop him. So far as he could tell, nothing had changed at all. He was still sitting right where he had been, on the left-hand focal point of the singularity coupling.
Maybe it was too soon. Only an instant had passed, after all. Maybe the displacement cone was still building up energy, still gathering the momentum it would need to hurl him across the centuries.
A moment later Sean started finding out how wrong he was.
That first moment of calm began to fade as bits of data came flooding into his mind: scattered and trivial bits at first, adding up very quickly into something overwhelming.Subtle wrongnesses became apparent, little ones that quickly grew bigger and bigger in his mind:
—Dr. Ludwig, who had been over by Eric’s side of the singularity coupling when the last switch was thrown, had moved to his left, barely outside the event horizon of the shunt field.
—Dr. White, who had been all the way across the big room in front of the bank of monitor screens frantically fidgeting with her thick curling hair, now was leaning against the frame of the lab door with her arms folded calmly.
—The computer printers, which had been standing silent in the moment before the throwing of the switch, were spewing copy like crazy. The frontmost one had an inch thick stack of pages in its hopper.
—Half a dozen technicians who had been scattered here and there around the room were gathered in a tight cluster just beyond the gleaming nickel-jacketed hood of the field shield. They were staring in at Sean as though he had sprouted a second head—or had lost the one he used to have.
—And more. The pattern of lights on the instrument panels was different. Someone had restrung the tangle of drooping gray cables on the back wall. And the video camera dolly had been pushed about halfway down the track in his direction. It had been in front of Eric before. At least a dozen tiny changes of that sort had been made.
It was, he thought, very much like one of those before and after blackout tests they give you when you’re a kid, when they want to measure your I.Q. They show you the image of a room, and then the screen goes dark, and a moment later it lights up and everything’s been moved around. You have to note down as many of the changes as you can pick out, within thirty seconds or so. That was what had happened here. In the twinkling of an eye, before had turned into after. Five minutes after.
So he really had taken a leap through time.
After all the months and months of planning and training and doubting and hoping, he had finally embarked on this fantastic voyage into the remote past and the far-off unknown future, a voyage that would unfold in a series of jumps. Small jumps at first, and then unimaginably vast.
Jump number one. He was five minutes in his own future. All the little changes around the room told him that.
And now he noticed the biggest change of all, the one he had somehow managed to keep blocked from his awareness until this moment.
—Eric wasn’t there anymore.
Eric’s three-legged aluminum chair was still there, to the right of the singularity coupling. But Eric himself was gone.
Sean felt dazed. A thick oily fog was trying to wrap itself around his brain. It was like a delayed reaction coming on, the whole crushing weight of the knowledge that he had actually been ripped out of space and time and then had been thrust back into place somewhere else.
“How do you feel, Sean?” Dr. Ludwig asked.
The words were like rolling thunder in Sean’s ears. He had to work hard to wring some sense from the blurred, booming sounds.
“Not bad,” he said automatically. “Not bad at all.”
He kept staring at the empty chair to his right, beyond the cone of the displacement torus. Eric wasn’t there. Eric wasn’t there. That was the only thought in his mind. Suddenly it had driven even the fact of the time voyage itself from the center of his consciousness.
For the entire twenty-three years of Sean’s life, Eric had always been there. Somewhere. Maybe not close at hand but always in some way there. They could be on opposite sides of the continent and yet they always remained aware of each other’s presence in some mysterious, indefinable way that neither of them tried to understand or explain. It had been like that for them all the way back to the beginning, to that time when they had shared the same womb, Eric lying beside him, jostling for space, poking his little arms and legs where they didn’t belong.