"I must say I don't see the necessity for that," Peterson said,
"considering the difficulty in sending the truly important–"
"It's to help anyone receiving on the other end," Markham said, stepping forward. He made his face resolutely neutral, though in fact he was rather distantly amused by the way the two other men seemed to immediately hit upon an area of disagreement, as though drawn to it.
"John here thinks it might help them to know when our beam will be easiest to detect. The astronomical coordinates–"
"I fully understand," Peterson cut him off. "What I don't understand is why you don't devote your quiet periods to the essential material."
"Such as?" Markham asked quickly.
"Tell them what we're doing, and repeat the ocean material, and–"
"We've done all that to death," Renfrew blurted. "But if they can't receive it, what bloody–"
"Look, look," Markham said mildly, "there's time enough to do it all, right? Agreed? When the noise goes down, the first priority should be sending that bank message of yours, and then John here can–"
"You didn't send it right away?" Peterson cried with surprise.
Renfrew said, "Ah, no, I hadn't finished the other material and–"
"Well!" Peterson seemed excited by this; he stood up quickly and paced energetically in the small space before the towering gray cabinets. "I told you about finding the note quite surprising, I must admit."
"Yes," Markham admitted. There had been considerable agitation when Peterson appeared this morning, bearing the yellow paper. Suddenly the entire thing had seemed real to them all.
"Well," Peterson went on, "I was thinking about your trying to, ah, extend the experiment."
"Extend?" Renfrew asked.
"Yes. Don't send my message."
"Good grief," was all Markham could say.
"But, but don't you see that ..." Renfrew's voice trailed off.
"I thought it would be an interesting experiment."
Markham said, "Sure. Very interesting. But it will set up a paradox."
"That was my idea," Peterson said swiftly.
"But a paradox is what we don't want," Renfrew said. "It'll bugger the whole idea."
"I explained that to you," Markham said to Peterson. "The switch being hung up between on and off, remember?"
"Yes, I understand that perfectly well but–"
"Then don't suggest rubbish!" Renfrew cried. "If you want to reach the past and know you have done it, then leave hands off."
Peterson said with glacial calm, "The only reason you do know is that I went to the bank in La Jolla. The way I see the matter is that I have confirmed your success."
There was an awkward silence. "Ah ... yes," Markham put in to fill the pause. He had to admit Peterson was right. It was precisely the kind of simple check he or Renfrew should have tried. But they were schooled in thinking of mechanical experiments, full of devices which operated without human intervention. The notion of asking for a confirming sign simply had not occurred to them. And now Peterson, the know-nothing administrator, had proved the whole scheme was right, and he had done it without any sophisticated thinking at all.
Markham took a deep breath. It was heady, realizing that you were doing something never accomplished before, something beyond your own understanding, but undeniably real. It had often been said that science at times put you into a kind of contact with the world that nothing else could. This morning, and Peterson's single sheet, had done that, but in a strangely different way. The triumph of an experiment was when you reached a fresh plateau of knowledge. With tachyons, though, they had no true understanding. There was only the simple note on a scrap of yellow.
"Ian, I know how you feel. It would be damned interesting to omit your message. But no one knows what that would mean. It might prevent us from doing what you want–namely convey the ocean information."
Renfrew underlined these sentiments with a "Damned right!" and turned back to the apparatus.
Peterson's eyelids lowered, as though he was deep in thought. "A good point. You know, for a moment there I thought there could be some way of finding out more that way."
"We could," Markham agreed. "But unless we do only what we understand ..."
"Right," Peterson said. "We rule out paradoxes, agreed. But later ..." He had a wistful look.
"Later, sure," Markham mtfrmured. It was odd, he thought, how the players had reversed roles here. Peterson was supposedly the can-do administrator, pressing for results above all else. Yet now Peterson wanted to push the parameters of the experiment and find out some new physics.
And opposing this were Renfrew and himself, suddenly uncertain of what a paradox might produce. Ironies abounded.
An hour later the fine points of logic had faded, as they so often did, before the gritty details of the experiment itself. Noise smeared the flat face of the oscilloscope. Despite earnest work from the technicians the jitter in the experiment would not diminish. Unless it did, the tachyon beam would be uselessly diffuse and weak.
"Y'know," Markham murmured, leaning back in his wooden lab chair,
"I think your Caltech stuff may bear on this, Ian."
Peterson looked up from reading the file with a red CONFIDENTIAL
stamped across it. During the lulls he had been steadily working his way through a briefcase of paperwork. "Oh? How?"
"Those cosmological calculations–good work. Brilliant, in fact.
Clustered universes. Now, suppose someone inside them is sending out tachyon signals. The tachyons can burrow right out of those smaller universes. All the tachyons have to do is pass through the event horizon of the closed-off microgeometry. Then they're free. They escape from the gravitational singularities and we can pick them up."
Peterson frowned. "These ... microuniverses ... are other ... other places to live? They might be inhabited?"
Markham grinned. "Sure." He had the serene confidence of a man who has worked through the mathematics and seen the solutions. There was a blithe certainty that came from first comprehending the full Einstein field equations, arabesques of Greek letters clinging tenuously to the page, a gossamer web. They seemed insubstantial when you first saw them, a string of squiggles. Yet to follow the delicate tensors as they contracted, as the superscripts paired with subscripts, collapsing mathematically into concrete classical entities potential; mass; forces vectoring in a curved geometry–that was a sublime experience. The iron fist of the real, inside the velvet glove of airy mathematics. Markham saw in Peterson's face the hesitant puzzlement that swam over people when they struggled to visualize ideas beyond the comforting three dimensions and Euclidean certainties which framed their world. Behind the equations were immensities of space and dust, dead but furious matter bending to the geometric will of gravity, stars like match heads exploding in a vast night, orange sparks that lit only a thin ring of child planets. The mathematics was what made it all; the pictures men carried inside their heads were useful but clumsy, cartoons of a world that was as subtle as silk, infinitely smooth and varied. After you had seen that, really seen it, the fact that worlds could exist within worlds, that universes could thrive within our own, was not so huge a riddle. The mathematics buoyed you.
Markham said, "I think that may be an explanation for the anomalous noise level. It's not thermally generated at all, if I'm right. Instead, the noise comes from tachyons. The indium antimonide sample isn't just transmitting tachyons, it's receiving them. There's a tachyon background we've neglected."
"A background?" Renfrew asked. "From what?"
"Let's see. Try the correlator."
Renfrew made a few adjustments and stepped back from the oscilloscope. "That should do it."
"Do what?" Peterson demanded.
"This is a lock-in coherence analyzer," Markham explained. "It culls out the genuine noise in the indium sample sound wave noise, that is–and brings up any signals out of the random background."
Renfrew stared intently at the oscilloscope face. A complex wave form wavered across the scale. "It seems to be a series of pulses strung out at regular intervals," he said. "But the signal decays in time."
He pointed at a fluid line which faded into the noise level as it neared the right side of the screen.
"Quite regular, yes," Markham said. "Here's one peak, then a pause, then two peaks together, then nothing again, then four nearly on top of each other, then nothing. Strange."
"What do you think it is?" Peterson asked.
"Not ordinary background, that's clear," Renfrew answered.
Markham said, "It's coherent, can't be natural."
Renfrew: "No. More like ..."
"A code," Markham finished. "Let's take some of this down." He began writing on a clip-board. "Is this a real-time display?"
"No, I just rigged it to take a sample of the noise for a hundred-microsecond interval." Renfrew reached for the oscilloscope dials. "Would you like another interval?"
"Wait till I copy this."
Peterson asked, "Why don't you just photograph it?"
Renfrew looked at him significantly. "We have no film. There's a shortage and priority doesn't go to laboratories these days, you know."
"Ian, take this down," Markham interrupted.
Within an hour the results were obvious. The noise was in fact a sum of many signals, each overlaid on the rest. Occasionally a short stuttering group of pulses would appear, only to be swallowed in a storm of rapid jiggling.
"Why are there so many competing signals?" Peterson asked.
Markham shrugged. He wrinkled his nose in an unconscious effort to work his glasses back up. It gave him an unintentional expression of sudden, vast distaste. "I suppose it's possible they're from the far future.
But the vest pocket universe sounds good to me, too."
Renfrew said, "I wouldn't put much weight on a new astrophysical theory. Those fellows speculate in ideas like stock brokers."
Markham nodded. "Granted, they often take a grain of truth and blow it up into a kind of intellectual puffed rice. But this time they have a point.
There are unexplained sources of infrared emission, far out among the galaxies. The microuniverses would look like that." He made a tent of his fingers and smiled into it, his favorite academic gesture. At times like these it was comforting to have a touch of ritual to get you through. "That scope of yours shows a hundred times the ordinary noise you expected, john. I like the notion that we're not unique, and there is a background of tachyon signals. Signals from different times, yes. And from those microscopic universes, too."
"It comes and goes, though," Renfrew observed. "I can still transmit a fraction of the time."
"Good," Peterson said. He had not spoken for some while. "Keep on with it, then."
Renfrew said, "I hope the fellows back in 1963 haven't got the detector sensitivity to study this noise. If they stick to our signals–which should stand out above this background, when we're transmitting properly–they'll be all right."
"Greg," Peterson mused, his eyes remote, "there's another point."
"Oh? What?"
"You keep talking about the small universes inside ours and how we're overhearing their tachyon messages."
"Right."
"Isn't that a bit self-centered? How do we know we, in turn, are not a vest pocket universe inside somebody else's?"
Gregory Markham slipped away from the Cav in early afternoon.
Peterson and Renfrew were still unable to resist sniping at each other.
Peterson was obviously drawn to the experiment, despite his automatic habit of distancing himself. Renfrew appreciated Peterson's support, but kept pushing for more. Markham found the ornate dance between the two men comic, all the more so because it was virtually unconscious. With their class-calibrated speech patterns, the two men had squared off at the first differing vowel. If Renfrew had stayed a laborer's son he would have got along smoothly with Peterson, each knowing his time-ordained role.
As a man swimming in exotic academic waters, however, Renfrew had no referents. Science had a way of bringing about such conflicts. You could come out of nowhere and make your mark, without having learned any new social mannerisms. Fred Hoyle's stay at Cambridge had been a case in point. Hoyle had been an astronomer in the old mold of eccentric-seeker-after-truth, advancing controversial theories and sweeping aside the cool, rational mannerisms when they didn't suit his mood. Renfrew might well prove as remarkable as Hoyle, a working-class salmon swimming upstream all the way, if this experiment went through.
Most rising scientists from obscure backgrounds nowadays kept a neutral, bland exterior; it was safer. Renfrew didn't. The big modern research teams depended for progress on well-organized, smooth-running, large-scale operations, whose stability demanded a minimum of upsetting–what was the jargon–"interpersonal relationships." Renfrew was a loner with a sandpaper psyche. The odd point was that Renfrew was quite civil towards most people; only the deliberate flaunting of class symbols by such as Peterson set him off. Markham had watched class friction worsen in England for decades, catching glimpses on his occasional visits. Time seemed to strengthen the ties of class, much to the confusion of the condescending Marxists who tended the lumbering government programs. The explanation seemed clear to Markham: in the steepening economic slide, following on the rich years of North Sea off, people stressed differences, in order to keep alive their sense of self-worth.
Us against Them stirred the blood. Better to play that distracting, antique game than to face the gray grip of a closing future.
Markham shrugged, mulling this over, and walked along the Coton footpath back toward the solemn spires of town. He was an American and thus exempt from the subtle class rituals, a visitor given a temporary passport. A year here had acustomed him to the language differences; now phrases like "the committee are" and "the government have" didn't cause a stumble as the eye slid through the sentence. He now recognized Peterson's skeptical arch of the eyebrow and rising, dry, "Hmmmm?" as a well-honed social weapon. The graceful, adroit sound of Peterson's