Probability Sun

by Nancy Kress

  Dr. Singh said, “Hal?”

  Albemarle said, “The numbers correlate. A huge leap in the rate of decay occurred two-point-one E-years ago, and no rate change since.”

  Marbet said, “For us non-physicists, what does that mean?”

  “It means,” Rosalind Singh said in her precise voice, “that what Dr. Johnson said in her preliminary report fits the facts as they exist now. It’s at least possible that her ‘wave effect’ hit Nimitri and caused its massive radioactivity by destabilizing the nucleus of every element above atomic number seventy-five. In other words, the probability that each nucleus would emit a radioactive particle increased enormously. Of course, that doesn’t provide the cause of the phenomenon.”

  Gruber’s voice said, “The moon they towed to the tunnel was the cause!” at the same moment that Capelo said, “That’s why I love you, Roz. You keep us honest. No prematurely ejaculated conclusions for you, no matter what Gruber says in absentia. But I’ll bet my nonexistent soul that our sneezing geologist is right. Ol’ Syree’s wave effect was real, and it hit Nimitri, and it rolled on outward to hit World. Had to.”

  “Ja!” Gruber said.

  Kaufman said, “Much weakened? Did it obey the inverse-square law?”

  Albemarle said, “No way to tell until we take measurements on the rest of the system and compare them with the initial data from the Zeus.”

  Kaufman nodded. He was surprised at how interested he was in the answer.

  Marbet said to him quietly, “Fascinating stuff, isn’t it?”

  “To me, yes. To you?”

  “Not the science,” she admitted. “But the team interactions certainly are.”

  Again he wondered what she saw. He’d avoided asking her; her mission here wasn’t with the humans.

  “Lyle,” she said, as the others became involved in some debate about mathematics, not one word of which was intelligible to Kaufman, “we’re now in the World System. Don’t you think it’s time you told me about this Faller I’m supposed to be presented with?”

  “Not yet,” Kaufman said, “because so far there’s nothing to tell. The moment there is, I’ll put you in the data chain, Marbet. I promise.”

  “All right.” She went back to watching the mathematical debate.

  Kaufman didn’t know whether to feel piqued or pleased. She seemed to have no interest in him apart from her mission here. Or was it just that she trusted him to communicate anything important without her having to press?

  He studied the curve of her brown throat, pure and strong. In profile like this, the startlingly high, sharp cheekbone made a clean plane below one emerald eye. Soft auburn curls clustered over her small ear. On the lobe was a jade earring. She looked as precise as if she were carved, and yet the flesh on that perfect genemod throat moved in and out with the breath of warm life.

  Lyle Kaufman suddenly hoped she hadn’t caught him staring.

  Albemarle finally said huffily, “Well, naturally, if you think that, there’s no point in arguing.”

  “That’s true,” Capelo said, “because whatever I think must be right. I came eighty thousand light years for no other purpose than to be right when you’re wrong. I live for the pleasure of flattening stupid mathematical theories, and you’re supplying me with food and drink. Isn’t that right, Roz?”

  “You are correct on this one mathematical point,” Dr. Singh said, “but no, you are not always right. Now leave Hal alone, Tom, so he can do the analysis I’ve requested of him.”

  “You sound just like my daughter,” Capelo said, “ordering me around. I’m surrounded by bossy women. Lyle, remind them who’s in charge here.”

  “I am,” Kaufman said mildly, and was rewarded by Marbet’s turning to him with her amused, full-lipped smile.

  “Dinner, sir,” announced a serving cart, entering with a full, fragrant tray. And that was another problem. Except for sleep, the team now pretty much lived on the observation deck, working and talking and eating there. They had all been invited to take their meals in the wardroom, but this had not worked out very well. The officers of the Alan B. Shepard were the usual mixed lot off-duty, ranging from the sophisticated, music-loving executive officer to the communications officer, who had the foulest sense of humor Kaufman, during a long Army career, had ever encountered. Despite the differences among them, they were all Navy officers, military men and women first. They found Tom Capelo just too weird, and the presence of his little girls too inhibiting. Marbet Grant clearly unnerved them. Everyone knew who she Was. Kaufman saw the officers gazing at her sideways when they thought she wouldn’t notice, and he knew they were wondering what she noticed about them that they would rather keep hidden. Most of them didn’t meet her eyes.

  So a few days out from Earth, the project team had begun having its meals brought to the observation deck. Hal Albemarle dined in the wardroom occasionally, when he couldn’t stand Capelo any more. But Albemarle was always drawn back, afraid of missing something important. Kaufman felt the same way, but he scrupulously divided his meals between the wardroom and his fractious team.

  Two days later they went into orbit around the star system’s next planet, another lifeless rock. At the same time, Dieter Gruber was released from quarantine. Kaufman was glad to see him. Gruber’s enthusiasm for the project and his obliviousness of social tension were equally welcome.

  * * *

  The fifth planet from the system’s star also proved to be highly radioactive. In fact, it was just exactly as radioactive as Nimitri.

  “Run the data again,” Capelo said flatly.

  “I already ran it twice!” Albemarle retorted.

  “Then run it three times.”

  Albemarle did. It came up the same.

  Rosalind Singh said thoughtfully, “So the wave effect did not obey the inverse-square law. Interesting.”

  “More than that!” Dieter Gruber said. The big man was so excited he could not stay still. He prowled the observation deck like a huge golden cat, stopping every few minutes to stare at the dead planet rotating beyond the viewport. Gray and airless, it looked much like a smaller Nimitri.

  Kaufman wanted to be sure he understood. Only the five of them were on deck. Capelo, Singh, Gruber, and Albemarle were scientists. He was not. He said, “Does that mean that when the artifact that the Zeus was towing exploded, or was shot down, it gave out a different kind of wave than Syree Johnson reported finding when she examined the thing in orbit?”

  Rosalind Singh said patiently, “Yes, Lyle. Or, rather, not different in effect, because the data showed that all three times, the wave destabilized atoms with an atomic number above seventy-five. It happened in orbit, it happened at Nimitri, it happened here. But when Dr. Johnson deliberately activated the artifact in orbit, she did so at the lowest setting. It was marked in primes with the addition of the integer ‘one,’ you know, the way the space-tunnels are. On that occasion, the wave obeyed the inverse-square law. The data from her, the shuttle, and various orbital sensors are quite definite about that.

  “But when that same artifact ‘blew,’ it apparently set off a much stronger wave, perhaps at the strongest setting, and that wave does not seem to have obeyed the inverse-square law. It affected this planet just as strongly as it affected Nimitri, although they are fifty-six million kilometers apart.”

  Kaufman said, “So … does that mean it would have hit World just as strongly?”

  “Yes!” crowed Gruber. “And yet World did not go radioactive! That was because of the buried artifact! It was at the exact moment of explosion that the artifact reacted! The exact moment, with no delay for light-speed! Because they are entangled!”

  “You cannot know that yet, Dieter,” Rosalind Singh said mildly.

  “No? What other theories do you have, Dr. Singh?”

  “I won’t have any theories until I can include the fall-off as well.”

  Kaufman said, “And fall-off is…”

  “It describes how an effect weakens until it’s und
etectable. It must fade away with distance eventually, or it would affect the entire universe. We launched probes in the opposite direction from the planets, you remember, and they show a very abrupt fall-off of radiation at about six billion kilometers from the star. That’s a very strange decay. We have no equations that can account for it.”

  “We will get them,” said Dieter, the optimist. His blue eyes sparkled.

  Kaufman turned to study Capelo, who appeared oblivious of the entire conversation. He paced, thinking, his dark thin face taut with concentration. Seeing Capelo like that, Kaufman realized how different the man looked when he was thinking deeply. For the moment, all bitterness and mockery had vanished from his face. It left Capelo looking both younger and, curiously, more mature, capable of intense mental exploration from which he would not be distracted. There was something impressive in his constantly moving figure. Even Albemarle did not interrupt.

  Gruber said, softly for him, to Kaufman, “You will see when we dig up the buried artifact, Colonel. It, too, alters probability. Like the exploded artifact altered the probability of any given atom going radioactive at any given time. The brain, too, is a probability field, and the buried one affects brains. I know, I felt it. You will see.”

  Kaufman had studied carefully this part of Gruber’s report. It was the part that had made High Command dismiss Gruber as a crackpot. The buried artifact, according to the geologist, affected the release of neurotransmitters in the brain, and, by existing on the planet for eons, had affected the mental evolution of the natives. More alarmingly, it had affected the brains of the human research team when they entered caves too close to the buried object.

  With such a claim, it had been all too easy to ridicule Gruber’s entire story. Yes, his brain had been affected. He’d been gassed by some hallucinogen, said one military doctor after another, or brainwashed by natives, or sent over the edge by some psychotropic he’d eaten.

  Kaufman had spent days poring over data cubes about the brain, trying to evaluate Gruber’s claim. Yes, there was a probability component to the release of neurotransmitters in the brain. For reasons no one understood, transmitters were not released each and every time an electrical impulse traveled along a brain nerve. The release rate varied from 17 percent to 62 percent, depending on the kind of nerve—even though the electrical impulse in each case was the exact same voltage. A single atom triggered or did not trigger the release of packets of transmitters. Whenever single atoms were involved, of course, you got quantum effects … and that brought in probability.

  Looked at that way, Gruber’s theory made sense.

  But no one had ever defined, measured, or created a “probability field.” It was a blue-sky concept. And even assuming such a thing existed, the idea of one that could be controlled violated practically every known idea of physics. At least, the level of physics that Kaufman could understand. On the other hand, so did the space tunnels, and they clearly existed. On the third hand, so did Tom Capelo’s ideas on probability, which some considered as crazy as Gruber’s. Capelo, however, was a figure not easily dismissed.

  As Kaufman understood contemporary physics, subatomic particles, however they were referred to, were not actually particles but tiny vibrating threads. That had been conclusively proven by the great Elisar Yeovil in 2041, building on work stretching back almost a century. All “particle” properties—charge, spin, mass—arose from differences in vibrational patterns of the fundamental threads. Spacetime was a rich fabric of threads twisting and vibrating throughout its four familiar dimensions and the six less familiar, tiny, curled-up dimensions that adjoined length, breadth, and height at every point in the universe.

  With the discovery of the graviton in 2052, gravity had finally been fully integrated into human understanding of the forces controlling spacetime. Gravitational fields were encoded into the warpings of the spacetime fabric, as an enormous—but not infinite—number of threads all vibrated in the same “graviton pattern.” The graviton—massless, spin-2, a perfect fit into the equations of both relativity and quantum mechanics—joined the gluon, the photon, and the gauge bosons as a “messenger particle,” a transmitter of a basic force.

  What made Tom Capelo look like a lunatic to so many of his fellows was his desire to account for probability amplitudes the same way: through an as-yet-undiscovered messenger “particle,” a new vibrational pattern, which Capelo dubbed the “probon.” Not only was the probon undiscovered experimentally, Capelo could not account for it mathematically except in the most obscure and roundabout way. Nor did he have any sort of coherent model. Capelo’s argument for the existence of the probon depended on equations too difficult for Kaufman to follow, equations ancillary to the existence of the six curled-up spatial dimensions conclusively proven to exist by the great Yeovil. The dimensions were usually called Calabi-Yau spaces, named for a particular class of geometric shapes. These tiny dimensions existed at every single point in spacetime. What Capelo had done so far was use the Sung-Rendell transformation equations to—

  “Colonel.” Commander Grafton stood by his side; Kaufman hadn’t even heard him approach. Kaufman couldn’t help smiling inwardly. Did that mean that he himself was capable of the same deep, unconscious-of-surroundings thought as Tom Capelo? Hardly to the same brilliant degree. He looked up at Grafton and saw what he should have noticed instantly.

  The Navy commander was taut with excitement. Being a Navy commander, his excitement had none of Gruber’s bluster or Capelo’s inward focus. Grafton stood straight as always, contained and military. But the line of his jaw, the look in his eyes, told Kaufman what must have happened.

  My God. They did it.

  But all Grafton said was, “Will you come with me, Colonel? There’s a message for you from the flyer.”

  “Yes, of course.” Kaufman rose and let himself be led from the observation deck. Capelo still paced, oblivious to everything but whatever rolled through his head. The other three speculated softly among themselves.

  In the corridor, Kaufman couldn’t wait. He said to Grafton, “They’ve captured a Faller, haven’t they? It worked. They’ve got one alive.”

  “Yes,” Grafton said, “alive,” and something in his tone made Kaufman remember reading Grafton’s personnel file as part of the preparation for this expedition. Grafton had had a brother killed in the battle with the Fallers in Quatorze system.

  He followed Grafton to the shielded communication room, where the encoded message from the flyer stationed at the space tunnel would have been received. The flyer itself would take days to catch up to its lightspeed message. But another ship must be enroute to World, carrying the first enemy alien ever captured in this long and inexplicable and unwelcome war.

  And then …

  “Send for Ms. Grant, please.”

  “She’s already on her way,” Grafton said. “There are datacubes for her to look at in the comm room.”

  “Good,” Kaufman said, and hoped it was. His breath came faster.

  Maybe humanity had a fighting chance after all.

  SIX

  FALLER SPACE, UNNAMED STAR SYSTEM

  Nothing about the plan had been simple. Thus, everyone was astonished when it actually worked. Some, in addition, felt a little ashamed, since the plan depended on the death of a child.

  The project team had arranged everything else ahead of time. All sat in readiness until the right child could be found. Two children were found suitable, but their parents refused. More than refused—they recoiled in horror when the plan was explained to them. One of the fathers struck Project Leader Colonel Ethan McChesney in the face, a blow of pure grief and rage. McChesney understood.

  Then, two and a half weeks after the Alan B. Shepard had flown into Space Tunnel #1 and left the solar system, Katrina Van Rynn fell off her brother’s power scooter in the colony of De Kooy, on New Holland. Katrina should not have been on the scooter. Her brother Michael, thirteen, had been warned that Katrina, four, was too young to ride behind him. She
might get scared, and he wasn’t yet experienced enough with the scooter. He took her for a ride anyway, because she begged and because he loved showing it off, even to a little sister. He belted her in securely and they set off over the low purple hills where Dutch settlers were recreating a mode of religious life that had all but vanished on Earth.

  Michael flew the scooter too high, and Katrina did get scared. She panicked, unlocked herself (Michael had not realized she knew how to do this), and climbed off. The scooter was thirty feet above the ground. The little girl died three hours later in the De Kooy medcenter.

  McChesney was already there. His intelligence network was among the best in the galaxy. Despite their terrible grief, the Van Rynns agreed to McChesney’s plan. They were patriots. They also hoped that the use McChesney would make of Katrina’s body might help Michael. The boy was wild with guilt. The family needed to salvage something, anything, out of what had happened to them all.

  Katrina’s body was flown by flyer to Space Tunnel #86, one of several that orbited the New Holland system, at the maximum speed the flyer and the corpse could sustain. Katrina wasn’t frozen. It was important that nothing be done to the body that would change its composition in any way.

  Seven tunnels later, the flyer reached Mowbray Base, a brand new military space station beside Tunnel #472. Orbiting beside both of them was another tunnel, #473, that gave onto an obscure Faller colony. Mapping tunnels was an intricate task. A ship that flew through a space tunnel and then eventually went back through the same tunnel would be returned to its place of origin—if nothing else had gone through the tunnel in the meantime. If something had, the first ship emerged in the same place the second one had. Much-used tunnels were thus fluid, requiring complex central routing in order to keep them focused on a given system.

  Tunnels #470 through #473, however, were not much used. Newly discovered and remote, they had been explored by only one human flyer. It had passed through #473, discovered the small Faller colony on the system’s single planet, and immediately popped back through the tunnel. The colony had not been military. It was possible the Fallers did not yet know that the star system had been discovered or visited by humans. McChesney gambled on that.