of his own ocean, carrying the elaborate scheme of the experiment as a multi-layered diagram in his mind, checking it against the never-perfect reality before him. He loved this thinking, correcting, and searching for the unseen flaw that could destroy the whole effect he wanted.
He had assembled most of this apparatus by scavenging among the other research groups in the Cav. Research had always been a highly visible luxury, easily cut. The past five years had been a disaster. When a group had been shut down, Renfrew had salvaged what he could. He had started out in the nuclear resonance group as a specialist in making beams of high-energy ions. This became important in the discovery of a completely new kind of subatomic particle, the tachyon, which had been theorized about for decades. Renfrew had moved over into that field. He had kept his small crew afloat by adroit grantsmanship and by using the fact that tachyons, as the newest of the new, had a clear intellectual claim to whatever funds remained in the National Research Council. The NRC had dissolved last year, though.
This year research was a puppet whose strings led to the World Council itself. The western nations had pooled their research efforts in a gesture towards economy. The World Council was a political animal. To Renfrew it seemed the Council’s policies boiled down to supporting highly visible efforts and little else. The fusion reactor program still got a lion’s share, despite no apparent progress. The Cav’s best groups, such as radio astronomy, had disbanded last year when the Council decided astronomy as a whole was impractical and such work should be suspended “for the duration.” Precisely how long the duration might be was a point the Council neatly dodged. The idea was that as the present crisis deepened the western nations had to shuck off their research luxuries in favor of sweaty-browed concentration on the ecoproblems and assorted disasters which dominated the newspaper headlines. But one had to sail with whatever wind was blowing, Renfrew knew. He had managed to find a way that tachyons could have a “practical” purpose, and that slant had kept his group afloat so far.
Renfrew finished calibrating some electronics gear—it was always going on the blink these days—and paused for a moment, listening to the preoccupied hum of the lab around him.
“Jason,” he called, “I’m off to get coffee. Keep it all going, will you?”
He picked his old corduroy jacket off a hook and stretched mightily, showing crescents of sweat in the cloth around his armpits. In mid-stretch he noticed two men on the platform. One of the technicians was pointing down at Renfrew, talking, and as Renfrew lowered his arms the other man started down the catwalk to the laboratory.
Renfrew had a sudden memory of his college days at Oxford. He had been walking down a corridor which gave back the hollow, ringing echo only stonework can. It was a beautiful October morning and he was brimming with eagerness to begin this new life he had looked forward to, the goal of the long student years. He had known he was bright; here, among his intellectual equals, he would at last find his niche. He had come in on the train from York the night before and now he wanted to get out into the morning sun and take it all in.
There were two of them sauntering towards him down the corridor. They wore their short academic gowns like courtiers’ robes and they walked as though they owned the building. They were talking loudly as they approached him and looked him over as if he were an Irishman. As they passed him, one said with a lazy drawl, “Oh, God, another bloody yokel up on a scholarship.” It had set the tone of his years at Oxford. He had got a First, of course, and he had made his name now in the physics world. But he had always felt that even if they were wasting their time, they were enjoying life more than he ever could.
The memory of it stung again as he watched Peterson walk towards him. At this distance in time, he could not remember the faces of those two undergraduate snobs and there was probably no physical resemblance, but this man wore the same graceful, arrogant self-assurance. Also, he noticed the way Peterson dressed and he resented noticing another man’s clothes. Peterson was tall and lean and dark-haired. At a distance, he gave the impression of a young and athletic dandy. He walked lightly, not like the rugby player that Renfrew had been in his youth, but like a tennis or polo player or perhaps even a javelin thrower. Seen closer, he looked to be in his early forties and was unmistakably a man used to wielding power. He was handsome in a rather severe way. There was no contempt in his expression, but Renfrew thought bitterly that he had probably just learned to hide it in his adult years.
“Good morning, Dr. Renfrew.” The smooth voice was just what he had expected.
“Good morning, Mr. Peterson,” he murmured, holding out a large square hand. “Pleased to meet you.” Damn, why had he said that? It might almost have been his father’s voice: “I’m reet pleased to meet ya, lad.” He was getting paranoid. There was nothing in Peterson’s face to indicate anything but seriousness about his job.
“Is this the experiment?” Peterson looked round with a remote expression.
“Yes, would you like to see it first?”
“Please.”
They passed some old gray cabinets of English manufacture and some newer equipment housed in brightly colored compartments from Tektronics, Physics International, and other American firms. These garish red and yellow units came from the small Council appropriation. Renfrew led Peterson to a complex array housed between the poles of a large magnet.
“Superconducting setup, of course. We need the high field strength to get a nice, sharp line during transmission.”
Peterson studied the maze of wires and meters. Cabinets housing rank upon rank of electronics towered over them. He pointed out a particular object and asked its function.
“Oh, I didn’t think you’d be wanting to know much of the technical side,” Renfrew said.
“Try me.”
“Well, we’ve got a large indium antimonide sample in there, see—” Renfrew pointed at the encased volume between the magnet poles. “We hit it with high-energy ions. When the ions strike the indium they give off tachyons. It’s a complex, very sensitive ion-nuclei reaction.” He glanced at Peterson. “Tachyons are particles that travel faster than light, you know. On the other side—” he pointed around the magnets, leading Peterson to a long blue cylindrical tank that protruded ten meters away from the magnets “—we draw out the tachyons and focus them into a beam. They have a particular energy and spin, so they resonate only with indium nuclei in a strong magnetic field.”
“And when they hit something in the way?”
“That’s the
Peterson said nothing. He scowled at the equipment.
“But when one of our tachyons strikes an indium nucleus in precisely the right state—a situation that doesn’t occur naturally very often—it will be absorbed. That tips the spin of the indium nucleus away from wherever it was pointing. Think of the indium nucleus as a little arrow that gets knocked to the side. If all the little arrows were pointing in one direction before the tachyons arrived, then they would get disordered. That would be noticeable and—”
“I see, I see,” Peterson said disdainfully. Renfrew wondered if he had overdone that bit about little arrows. It would be fatal if Peterson thought he was talking down to him—which of course he was.
“That’s some other fellow’s indium, I suppose?”
Renfrew held his breath. This was the tricky part. “Yes. An experiment operating in the year 1963,” he said slowly.
Peterson said drily, “I read the preliminary report. These prelims are often deceptive, but I understood that. The technical staff tell me it makes sense, but I can’t believe some of the things you’ve written. This business of altering the past—”
“Look, there’s this fellow Markham coming—he’ll put you straight on that.”
“If he can.”
“Right. See, the reason nobody’s even tried to send messages back is an obvious one, once you think of it. We can build a transmitter, see, but there’s no receiver. Nobody in the past ever built one.”
Peterson frowned. “Well, of course—”
Renfrew went on enthusiastically.
