Einstein's Bridge

by Cramer, John

George was an experimentalist with the LEM collaboration here. He was older, perhaps forty five, and had held a string of research positions at CERN and Fermilab before he landed his present tenured faculty job at a big university somewhere on the North Pacific coast of the US. Was it Oregon? Roger couldn’t remember. “Hello George,” he said more cheerfully than he felt. “Good to see you again.”

  “Good afternoon, Roger,” said George. “Welcome to Waxahachie. How do you like the New World?”

  “I like it well enough, so far,” said Roger. “How are you? We must do a bit of pub crawling soon, assuming we can find crawlable pubs in this arid landscape.”

  “My informants tell me,” said George, “that in Texas pub crawling is called ‘juking’. It has to do with moving from one juke joint to the next until you must stop because you either run out of quarters or can’t make it back up on your horse.” He grinned.

  Roger laughed. He had difficulty in imagining George sharing the same roof with a functioning juke box.

  “But actually, Roger, I dropped by to ask you a theoretical question. Is this a good time?”

  Roger glanced quickly at his desk drawer. Yes, it was indeed closed and locked. “Of course,” he said and stood aside to offer George a chair. He glanced at his workstation screen. “Actually, I’ve just finished a project.” As Roger sat at his own desk chair, he noticed that the tingling feeling had migrated from his thigh up to the base of his spine. He could feel the twitching of muscles in his buttocks. He looked across at George. “What’s up?” he asked.

  “I’ve only had about four hours sleep since my night shift, but I need to talk to someone. I’ve been puzzling over a very peculiar collision event that the LEM detector recorded in the wee hours this morning,” he said. “It cannot plausibly have been produced by the usual suspects, event pileup or equipment failure, yet it violates several of my favorite laws of physics. It seems to be legitimate.”

  Roger rubbed his chin. “So the laws of physics were overthrown overnight?” he said. “I hadn’t heard, George. You must tell me about it.” The twitching sensation was moving progressively up his spine. But now it felt rather pleasant, like a back rub.

  George described the LEM event and showed Roger the colorful hardcopy details of the event’s characteristics, graphs, histograms, tables.

  Roger thumbed through the sheets of printout. It was very complex, and the format was unfamiliar. But somehow he was able to grasp the densely packed information on each page almost at a glance. As he did this, a remote corner of his consciousness was considering model after model that might explain the data and rejecting each in turn as inappropriate. It was quite enjoyable. Roger was beginning to feel very good as he warmed to the task.

  There was a multitude of models to sort through. Three generations of particle theorists had made it their business to fill the physics literature with every possible twist on what at any given time was called “The Standard Model.” Every conceivable variation that could be wedged into an unoccupied corner of “theory space” had been published and promoted by its progenitor. It had been a gold rush of ideas. The losing theorists had their papers published, perhaps had their ideas tested against reality by some hyperactive experimental group, and usually had their work listed a few times in the Citation Index. The winners, those with enough of “the right stuff” to hit upon a combination of theoretical ideas that happened to map, at least momentarily, into the actual structure of the physical universe, became famous, received Nobel prizes, were given endowed chairs in physics, and were asked to sign numerous petitions expressing outrage at or support for various social and political issues and causes.

  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. “OK,” 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 1930’s 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 fixes 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 han
g 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 Waxahachie Court House, 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.

  CHAPTER 4.8

  Confrontation

  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 six feet, 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.”

  Jake paused and seemed to be absorbing the idea, then grinned. “Superb thinking, Murray,” he said, clapping him on the back. “Do it! I’ll check with you later.” He turned to the remote.. “Hello, George,” he said. “You were on the owl shift last night, and I didn’t expect to see you until tomorrow. You should be sleeping. Where are you?”

  George wondered if Jake had heard about the Snark event yet. He put on what he hoped was a charming grin. “I’m upstairs in my office,” he said. “I’ll sleep later, Jake. I was giving Ms. Lang a demonstration of the use of remotes, and I found you here. Jake, I need to talk to you about an event we recorded early this morning. It’s now our leading candidate for weird event of the year,” he said.

  Jake frowned. “Weird in what way?” he asked.

  Apparently the news hadn’t reached him, George thought. The students and postdocs were afraid of Jake and didn’t talk to him if they could avoid it. “Well,” he began, “in most ways it’s a normal collision. The Fermi motions of both interacting quarks must have boosted the collision energy a bit, but otherwise it’s very much like our other central collisions except for one thing. There’s an extra particle coming from the vertex. A most unusual extra particle.”

  “Unusual?” Jake said. George noticed that the brightness of his brown eyes seemed to intensify. He was interested. “Exactly what kind of unusual particle, George?”

  George gestured with the remote’s right arm and metal hand. “First, it’s not a Higgs, Jake,” he said quickly and watched as the brightness faded. “It’s not any particle that you could hang a theorist’s label on. It came straight out of the vertex, leaving a huge ionization trail but not a trace of any deflection in the magnetic field. It made a new jet every few millimeters, 29 jets in all, and all of them pointing roughly forward in the momentum direction of the particle. But the inner time-of-flight system claims the thing was only moving at about 2% of the speed of light when it went by. It has to be massive as hell.”

  “Couldn’t you get its mass from the missing energy?” Jake asked.

  George shook his head, hearing the remote’s motors whirr as he did so. “No missing energy, Jake. The event conserves energy and momentum only when the extra particle is removed from the analysis.”

  Jake stared in George’s direction for a moment, then broke into a peal of ironic laughter. “You mean ...” he said, then stopped to laugh again. “You mean that you’ve not only discovered a new particle of great mass, George, but you’ve also discovered a violation of energy conservation! And momentum conservation too, no doubt!” He lapsed into laughter again, stopped abruptly to frown at George, then turned on the Stare.

  Then, quite abruptly, the Stare was transformed into a broad smile. “We shall call a press conference immediately to announce your great discovery, George. We must give a name to this remarkable new particle of yours. I know! We’ll name it after you! We’ll announce to the assembled multitudes of reporters that you’ve discovered the ...” He broke into laughter again. “... the George-on! Or wait! Perhaps it’s neutral. We could call it the George-ino!”

  He turned the Stare on George again, his gaze seemingly focused some distance behind the remote’s head. This lasted for what seemed a full minute.

  George waited for what he had learned was the appropriate length of time, enduring the Stare as he patiently monitored the seconds on the telepresence chronometer floating at the upper right of his field of view. Finally he spoke. “You’re the LEM Spokesman, Jake.” he said quietly. “You need to look at the data on this thing yourself. If you don’t, you aren’t doing your job.”

  Jake’s frown deepened. “George, you’re wasting my time,” he said. “You’re looking at a cosmic ray or a fission fragment or some glitch in the detector electronics and trying to make it into something important. Face it, George. If it doesn’t conserve energy, it isn’t physics.”

  “At least think about it, Jake,” said George. “Let’s not get too hung up on conventional wisdom. There is a possible mechanism. I have a theorist friend who suggested ...”

  “George, ... No! You’re wasting my time,” Jake said, his voice smooth but very deep and low.

  “OK, Jake,” said George, “but I think it’s important. I’m going to follow up on it, and I’m going to use LEM resources.”

  Jake uttered a deep sigh. “Just what do you want to do with this wonderful magic event you’ve discovered, George?”

  “I’ll use processor time to do a detailed scan of all the event tapes to see if there are any more like it that the anomaly system missed. And I want to retrain the neural net of the event-trigger to be more sensitive to anything similar in the next run. Jake, I have a feeling about this event. It’s important.”

  Jake frowned. “You don’t have enough to do already
, George? You’re in need of new projects? You don’t have enough to do in discovering why our vertex detector is dying? The tens of millions of dollars invested in that vertex detector are going down the drain while you pursue fantasies. You need to retrain the trigger, too? That’s a month’s work, George. Every time we try to retrain that trigger network, it does ugly things to us. It’s working now, George. Leave it alone!”

  “Jake,” said George, “I want you to look at this event. Please. It’s important.”

  “No!” Jake shouted. “Absolutely not. I have better things to do. You have better things to do. The whole damned experiment is collapsing around us, and you want to repeal conservation of energy. Get some sleep, George. Tomorrow this will all seem like a bad dream.”

  Jake looked at his watch, then moved his hand in a dismissive manner. “I must go, George. I have to go talk to Roy again. Now those SDC imbeciles have done something to the sextupoles that is destroying our beam quality. We have the next group meeting on Monday morning, George. Be there, with your report on your progress toward understanding and fixing the pixel problem and without this event you found in the garbage can.” He spun on his heel and stalked out of the room.

  George angrily wheeled the remote, its motors howling, to the nearest charging dock and disconnected.

  CHAPTER 4.9

  Shootout

  ALICE removed the magic glasses that had been patched into George’s, placed them in their holder, and looked across the office at him.

  His face was red, and he seemed to be breathing deeply. “That was Jake at close range,” George said finally.

  Alice had been a passive participant in the confrontation. She was embarrassed at what she had just witnessed. She didn’t understand why George had approached Jake as a remote when he had such an important matter to discuss, or why he had included her as an observer. During the past few days she had interviewed a number of physicists from LEM and other groups at the SSC. She’d found a wide range of viewpoints on many topics. But about Jake there were only two common views: Jake was a great world-class physicist who would soon win a Nobel prize, or Jake was a madman who was leading his group to disaster. She nodded finally. “Is he always like that? How do you stand it?”