But the forward march of particle physics had left in its wake a vast array of theoretical ideas and formalisms that were relegated to the limbo of untestable theories. These were neither confirmed nor falsified, neither accepted nor rejected because, at any given time, there was no feasible way to test them. It was these theories that Roger was somehow dredging up from his voracious reading of the physics literature, was comparing one at a time to George’s event, and was tossing aside, one by one.
Finally Roger paused. “Perhaps your collision event only acted as the trigger for something else,” he said quietly. “Perhaps it was a stimulated emission.”
“Stimulated emission?” George said. “You mean like a laser?”
“Yes,” said Roger. “In a way. To make a laser work, you have to create a population inversion, to kick most of the available atoms up into an excited state where they hang, all ready to emit a photon. Then, if a photon like the ones that the atoms are trying to make happens to pass by, it triggers some atom to emit and you get a second photon. And the two of them can trigger more, and so on.
“What I was thinking is that your event, assuming it isn’t some detector fluke, may have triggered some otherwise exceedingly rare process that made the track with all the jets. Your collision didn’t make your peculiar massive particle. It only triggered the process that created it, perhaps out of the vacuum itself.”
George frowned and was silent for a time. “Okay,” he said at last, “but I don’t see how that solves the problem of violating energy and momentum conservation. You’re saying that the energy came from the vacuum?”
Roger shrugged. “If you didn’t know the population inversion was there in a laser, the photons would seem to come from nowhere and you would think that energy conservation was being violated. Do you recall how Pauli deduced the existence of the neutrino?”
George shook his head.
“In the 1930s measurements of beta decay processes seemed to be indicating violations of energy conservation, momentum conservation, and spin conservation, all at once. So Pauli invented the neutrino, a neutral particle that carried off the missing energy, momentum, and spin, and at a stroke fixed all the conservation laws.
“Now, Pauli’s neutrino was in the final state. Suppose there’s something large, neutral, and energetic, perhaps dark matter, hanging there in an initial state. Your central collision, with its enormous energy density, triggers that system into emitting your particle.”
“Really?” said George. “Is there any theoretical basis for such an object?”
Roger laughed. As he did so, he felt his neck and back muscles twitch again. “Surely you jest,” he said. “I could reel off a dozen hypothetical particles that could be pressed into service. It’s definitely strongly interacting. From the jets it’s producing it must be producing color ionization, kicking loose quarks as it goes by the way a charged particle kicks loose electrons with its electric field.
“But some wild-eyed theoretical speculation is not what you need at the moment. You can’t support a half-baked experiment with a half-baked theory. You need to find more events with the same signature. If you can show that it happens more than once, you might be able to attract a few believers. Perhaps even me.” He looked sharply at George.
“You’re not convinced?” said George.
Roger studied the brightly colored representation of the event. “It’s beautiful data,” he said, “and I’d love to believe it was the first inkling of some brand-new physical phenomenon. But my good sense tells me that it’s far more likely to be some fluke or glitch in the equipment. You need more evidence, George.”
“I’ve already looked for similar events in our data. There are none. What if this stimulated emission process of yours is very rare? What if it only happens once in ten years? Or a hundred?”
“Then you’re well and truly screwed,” Roger said. “Unless…” An interesting idea had suddenly popped into his head.
“Unless…?” said George.
“Unless your mystery particle is stable. Perhaps a quarter of the hypothetical particles that I could conjure up for you from the dregs and leftovers of theoretical physics are simply too weird to decay into normal particles, so they must hang around. They possess conserved quantum numbers that they can’t easily get rid of.”
“Then,” said George, “the damned thing could have stopped somewhere in the LEM detector and still be sitting there…”
“Or in the walls of the tunnel, or on the dome of the Ellis County Courthouse, or it could be well on its way out of the solar system,” said Roger. He was beginning to develop a nasty headache. “Anyhow, do some kinematic reconstruction. Assume that your particle has a Planck mass. About a microgram, say. Assume it’s losing energy like mad, perhaps in the color ionization that’s producing all those jets. From that energy loss and your time of flight information you should be able to roughly estimate how far it’s going to travel. Or perhaps check your detector for any odd instrumental behavior along the flight path of your mystery particle.”
Roger winced as his headache intensified. As he had been talking to George, he realized, several new approaches to his QCD perturbation problem had occurred to him. One of them was so radical and beautiful that it hurt him to think about it. But it was a pleasant pain. He stood up. “I’m afraid you’ll have to excuse me now, George,” he said. “I’m much in need of some aspirin for a roaring headache that just came on.
“And I have a load of work to do. I have to prepare for my particle theory seminar tomorrow afternoon. I’ve just given birth to a brand-new and very beautiful brick of an idea, which I’m going to use to bash out the brains of my colleagues.” He was amused by the thought.
27
GEORGE BLINKED AND TURNED HIS HEAD TO THE RIGHT, hearing as he did so the motor whirr of the remote he had just linked into. He recognized his new location as the charging dock of the LEM counting house. He looked in the wall mirror, saw his own familiar features on the headscreen, and adjusted the height of the remote to one hundred eighty centimeters, matching his own. Across the room he could see Jake Wang, impeccably attired in a pearl-gray business suit. He was talking to and gesturing at Murray, clad as usual in yellow SSC coveralls.
“You have to get those new transputer chips for us, Murray,” Jake said. “There’s no alternative. The machine people are improving the luminosity, and as the data rate goes up, we’re getting more and more dead time. It would be a great embarrassment if I had to ask them to turn down the luminosity to keep our electronics from hanging. We must have those faster transputer chips.”
“Sure, Jake,” said Murray. “Maybe I should call up the Secretary of the Navy and tell him that his jets don’t need fast transputer VLSIs in their radar. Maybe…” He stopped talking and looked thoughtful. “You know, I do have a friend in the testing and quality control department at Inmos. We used to work together at Motorola. Last time I talked to him, he was complaining about how much trouble they were having with testing their new transputer chips for radiation damage. Their sources weren’t hot enough or didn’t have the right spectrum or something. Maybe we could, uh, volunteer to help him out with some of the testing. Any transputer chip that can survive in the middle of the LEM detector should have no problem at all in a nuclear war.”