Timelike Infinity

by Stephen Baxter

  Schrödinger had developed equations that described how probability waves shifted and evolved, in the presence of other particles and forces. Parz closed his eyes. "I imagine space filled with probability, like blue ripples. If I had vision good enough, maybe I could see the waves in all their richness. But I can't. It's like looking through half-closed eyes; and all I can make out is the shadowy places where the peaks and troughs occur. And I say to myself — there, that's where the electron is. But it isn't; it's just a crest of the wave... Where the wave function has its peaks is where I'm most likely to find my electron — but it's not the only possibility."

  "But the wave functions collapse on observation, of course," the Qax prompted.

  "Yes." The link between quantum reality and the world of the senses — human senses — came when measurements were made. "I run my experiment and determine that the electron is, in fact, at this instant" — he stabbed the tabletop with a fingertip — "right there. Then the position wave function has collapsed — the probabilities have all gone to zero, except in the little region of space within which I've pinned down the electron. Of course, as soon as the measurement is over the wave functions start evolving again, spreading out around the electron's recorded position." Parz frowned. "So by observing, I've actually changed the fundamental properties of the electron. It's not possible to separate the observer from the observed... and you could argue that by observing I've actually evoked the existence of the electron itself.

  "And there lies the mystery. The paradox. Schrödinger imagined a cat locked in a box with a single unstable nucleus. In a given period there is a fifty-fifty chance that the nucleus will decay. If it does, the cat will be killed by a robot mechanism. If it doesn't, the cat is allowed to live.

  "Now. Leave the box aside for its specified period, without looking inside. Tell me: is the cat alive or dead?"

  The Qax said without hesitating, "There is no paradox. One can only give an answer in terms of probabilities, until the box is opened."

  "Correct. Until the box is opened, the wave function of the box-cat system is not collapsed. The cat is neither alive nor dead; there is equal probability of either state.

  "But Wigner took Schrödinger's paradox further. Suppose the box was opened by a friend of Wigner's, who saw whether the cat was alive or dead. The box, cat, and friend would now form a larger quantum system with a more complex wave function in which the state of the cat — and the friend — remained indefinite until observed by Wigner or someone else.

  "Physicists of the time called this the paradox of Wigner's Friend," Jasoft said. "It leads to an infinite regress, sometimes called a von Neumann catastrophe. The box-cat-friend system remains indefinite until observed, say by me. But then a new system is set up — box-cat-friend-me — which itself remains indefinite until observed by a third person, and so on."

  The Qax pondered for a while. "So we have, in human eyes, the central paradox of existence, of quantum physics, as set out by this Wigner and his chatter of cats and friends."

  "Yes." Jasoft consulted his slate. "Perhaps external reality is actually created by the act of observation. Without consciousness, Schrödinger wondered, 'Would the world have remained a play before empty benches, not existing for anybody, thus quite properly not existing?' "

  "Well, Jasoft. And what does this tell us about the mind-set of those who style themselves the Friends of Wigner?"

  Parz shrugged. "I'm sorry, Governor. I've no hypothesis."

  There was a lengthy silence then; Parz peered through the port of the flitter at the unblinking eye of the Spline.

  Suddenly there was motion at the edge of Parz's vision. He shifted in his seat to see better.

  The Spline freighter was changing. A slit perhaps a hundred yards long had opened up in that toughened epidermis, an orifice that widened to reveal a red-black tunnel, inviting in an oddly obscene fashion.

  "I need your advice and assistance, Ambassador," the Governor said. "You'll be brought into the freighter."

  Anticipation, eagerness, surged through Parz.

  The flitter nudged forward. Parz strained against his seat restraints, willing the little vessel forward into the welcoming orifice of the Spline.

  * * *

  The flitter passed through miles, it seemed, of unlit, fleshy passages; vessels bulging with some blood-analogue pulsed, red, along the walls. Tiny, fleshy robots — antibody drones, the Governor called them — swirled around the flitter as it traveled. Parz felt claustrophobic, as if those blood-red walls might constrict around him; somehow he had expected this aspect of the Spline to be sanitized away by tiling and bright lights. Surely if this vessel were operated by humans such modifications would be made; no human could stand for long this absurd sensation of being swallowed, of passing along a huge digestive tract.

  At last the flitter emerged from a wrinkled interface into a larger chamber — the belly of the Spline, Parz instantly labeled it. Light globes hovered throughout the interior, revealing the chamber to be perhaps a quarter mile wide; distant, pinkish walls were laced with veins.

  Emerging from the bloody tunnel into this strawberry-pink space was, Parz thought, exactly like being born.

  At the center of the chamber was a globe of some brownish fluid, itself a hundred yards wide. Inside the globe, rendered indistinct by the fluid, Parz could make out a cluster of machines; struts of metal emerged from the machine cluster and were fixed to the Spline's stomach wall, so anchoring the globe. A meniscus of brownish scum surrounded the globe. The fluid seemed to be slowly boiling, so that the meniscus was divided into thousands, or millions, of hexagonal convection cells perhaps a hands-breadth across; Parz, entranced, was reminded of a pan of simmering soup.

  At length he called: "Governor?"

  "I am here."

  The voice from the flitter's translator box, of course, gave no clue to the location of the Governor; Parz found himself scanning the stomach chamber dimly. "Where are you? Are you somewhere in that sphere of fluid?"

  The Qax laughed. "Where am I indeed? Which of us can ask that question with confidence? Yes, Ambassador; but I am not in the fluid, nor am I of the fluid itself."

  "I don't understand."

  "Turbulence, Parz. Can you see the convection cells? There am I, if 'I' am anywhere. Do you understand now?"

  Jasoft, stunned, stared upward.

  * * *

  The home planet of the Qax was a swamp.

  A sea, much like the primeval ocean of Earth, covered the world from pole to pole. Submerged volcano mouths glowed like coals. The sea boiled: everywhere there was turbulence, convection cells like the ones Parz saw in the globe at the heart of the Spline.

  "Parz, turbulence is an example of the universal self-organization of matter and energy," the Qax said. "In the ocean of my world the energy generated by the temperature difference between the vulcanism and the atmosphere is siphoned off, organized by the actions of turbulence into billions of convection cells.

  "All known life is cellular in nature," the Governor went on. "We have no direct evidence, but we speculate that this must apply even to the Xeelee themselves. But there seems to be no rule about the form such cells can take."

  Parz scratched his head and found himself laughing, but it was a laughter of wonder, like a child's. "You're telling me that those convection cells are the basis of your being?"

  "To travel into space I have been forced to bring a section of the mother ocean with me, in this Spline craft; a small black hole at the center of the Spline sets up a gravity field to maintain the integrity of the globe, and heaters embedded at the core of the fluid simulate the vulcanism of the home sea."

  "Not too convenient," Parz said dryly. "No wonder you need a Spline freighter to travel about in."

  "We are fragile creatures, physically," the Governor said. "We are easily disrupted. There are severe constraints on the maneuverability of this freighter, if my consciousness is to be preserved. And there are comparatively few of us compar
ed to, say, the humans."

  "Yes. There isn't much room, even in a planet-wide sea..."

  "The greatest of us spans miles, Parz. And we are practically immortal; the convection cells can readily be renewed and replaced, without degradation of consciousness... You will understand that this information is not to be made available. Our fragility is a fact that could be exploited."

  This warning sent a chill through Parz's old bones. But his curiosity, drinking in knowledge after years of exclusion, impelled him to ask still more questions. "Governor, how could the Qax ever have got off the surface of their planet and into space? You're surely not capable of handling large engineering projects."

  "But we are nevertheless a technological race. Parz, my awareness is very different from yours. The scales are different: I have sentience right down to the molecular level; if I wish my cells can operate as independent factories, assembling high technology of a miniaturized, biochemical nature. We traded such items among ourselves for millions of years, unaware of the existence of the rest of the universe.

  "Then we were 'discovered'; an alien craft landed in our ocean, and tentative contact was established—"

  "Who was it?"

  The Governor ignored the question. "Our biochemical products had enormous market value, and we were able to build a trading empire — by proxy — spanning light-years. But we must still rely on clients for larger projects—"

  "Clients like humans. Or like the Spline, who cart you around in their bellies."

  "Few of us leave the home world. The risks are too great."

  Parz settled back in his chair. "Governor, you've known me for a long time. You must know how I've been driven crazy, for all these years, by knowing so little about the Qax. But I'm damn sure you haven't shown me all this as a long-service reward."

  "You're correct, Ambassador."

  "Then tell me what you want of me."

  The Governor replied smoothly. "Parz, I need your trust. I want to travel to the future. I want humans to build me a new time Interface. And I want you to direct the project."

  It took Parz a few minutes to settle his churning thoughts. "Governor, I don't understand."

  "The revival of the ancient exotic matter technologies should not be difficult, given the progress of human science in the intervening millennium and a half. But the parameters will differ from the first project..."

  Parz shook his head. He felt slow, stupid, and old. "How?"

  Through the flitter's tabletop the Qax transmitted an image to Parz's slate: an appealing geometrical framework, icosahedral, its twenty sides rendered in blue and turning slowly. "The new Interface must be large enough to permit the passage of a Spline freighter," the Governor said. "Or some other craft sufficient to carry Qax."

  A traveler through a wormhole interface suffered gravitational tidal stresses on entering the exotic-matter portal framework, and on passing through the wormhole itself. Parz had been shown, now, that a Qax was far more vulnerable to such stress than a human. "So the throat of the wormhole must be wider than the first," he mused. "And the portals must be built on a larger scale, so that the exotic-matter struts can be skirted—"

  Parz touched the slate thoughtfully; the geometrical designs cleared.

  The Qax hesitated. "Parz, I need your cooperation on this project." There seemed to be a note of honesty, of real supplication, in the Governor's synthesized voice. "I have to know if this will cause you difficulty."

  Parz frowned. "Why should it?"

  "You are a collaborator," the Qax said harshly, and Parz flinched. "I know the ugliness that word carries, for humans. And now I am asking you to collaborate with me on a project whose success may cause great symbolic damage to humans. I am aware of how much the small success of the time-journeying rebels has meant to humans, who see us as oppressive conquerors—"

  Parz smiled. "You are oppressive conquerors."

  "Now, though, I am asking you to subvert this emblem of human defiance to the needs of the Qax. I regard this as an expression of great trust. Yet, perhaps, to you this is the vilest of insults."

  Parz shook his head, and tried to answer honestly — as if the Qax were an externalization of his own conscience, and not a brooding conqueror who might crush him in an instant. "I have my views about the Qax Occupation, my own judgments on actions you have taken since," he said slowly. "But my views won't make the Qax navies go away, or restore the technologies, capabilities, and sheer damn dignity that you have taken from us."

  The Qax said nothing.

  "I am a practical man. I was born with a talent for diplomacy. For mediation. By doing the job I do, I try to moderate the bleak fact of Qax rule into a livable arrangement for as many humans as possible."

  "Your fellows might say that by working with us you are serving only to perpetuate that rule."

  Parz spread his age-pocked hands, finding time to wonder that he was speaking so frankly with a Qax. "Governor, I've wrestled with questions like this for long hours. But, at the end of it, there's always another problem to address. Something urgent, and practical, which I can actually do something about." He looked up at the ball of slowly seething liquid. "Does that make any sense?"

  "Jasoft, I think we are of like mind, you and I. That is why I chose you to assist me in this enterprise. I fear that the precipitate actions of these rebels, these Friends of Wigner, represent the gravest peril — not just to the Qax, but perhaps to humanity as well."

  Parz nodded. "That thought's occurred to me too. Meddling with history isn't exactly a proven science... and which of us would wish to trust the judgment of these desperate refugees?"

  "Then you will help me?"

  "Governor, why do you want to travel forward in time? How will that help you with your problem from the past?"

  "Don't you see what an opportunity this technology represents? By constructing a portal to the future I can consult with an era in which the problem has already been addressed and resolved. I need not make a decision on this momentous matter with any uncertainty about the outcome; I can consult the wisdom of those future Qax and refer to their guidance..."

  Parz wondered vaguely if some sort of time paradox would be invoked by this unlikely scheme. But aloud he said, "I understand your intention, Governor. But — are you sure you want to do this? Would it not be better to make your own decisions, here and now?"

  The Governor's interpreted voice was smooth and untroubled, but Parz fancied he detected a note of desperation. "I cannot take that risk, Parz. Why, it's entirely possible I will be able to consult myself... a self who knows what to do. Will you help me?"

  The Qax is out of its depth, Parz realized. It genuinely doesn't know how to cope with this issue; the whole of this elaborate new Interface project, which will absorb endless energy and resources, is all a smokescreen for the Governor's basic lack of competence. He felt a stab of unexpected pride, of chauvinistic relish at this small human victory.

  But then, fear returned through the triumph. He had been honest with the Governor... Could he really bring himself to trust the judgment of these Friends of Wigner, to whom accident had provided such power?

  And, surely, this victory of procrastination would increase the likelihood that they'd all be left helpless in the face of the wave of unreality from the past.

  But, Parz reflected, he had no choices to make.

  "I'll help you, Governor," he said. "Tell me what we have to do first."

  Chapter 4

  WITH HER MESSAGE TO MICHAEL Poole dispatched and still crawling over the Solar System at mere lightspeed, Miriam Berg sat on coarse English grass, waiting for the Wigner girl Shira.

  Berg had built a time machine and carried it to the stars. But the few days of her return through the wormhole to her own time had been the most dramatic of her life.

  Before her the lifeboat from the Cauchy lay in a shallow, rust-brown crater of scorched soil. The boat was splayed open like some disemboweled animal, wisps of steam escaping its still-glowi
ng interior; the neat parallel slices through its hull looked almost surgical in their precision, and she knew that the Friends had taken particular pleasure, in their own odd, undemonstrative way, of using their scalpel-like cutting beams to turn drive units into puddles of slag.

  The — murder — of her boat by the Friends had been a price worth paying, of course, for getting her single, brief message off to Poole. He would do something; he would be coming... Somehow, in formulating her desperate scheme, she had never doubted that he would still be alive, after all these years. But still she felt a twinge of conscience and remorse as she surveyed the wreckage of the boat; after all this was the destruction of her last link with the Cauchy — with the fifty men, women, and children with whom she had spent a century crossing light-years and millennia — and who were now stranded on the far side of the wormhole in the future they had sought so desperately to attain, that dark, dehumanized future of the Qax Occupation.

  How paradoxical, she thought, to have returned through the wormhole to her own time, and yet to feel such nostalgia for the future.

  She lay on her back in the grass and peered up at the salmon-pink clouds that marbled the monstrous face of Jupiter. Tilting her head a little she could still make out the Interface portal — the wormhole end that had been left in Jovian orbit when the Cauchy departed for the stars, and through which this absurd earth-craft of the Friends of Wigner had come plummeting through time. The portal, sliding slowly away from the earth-craft on its neighboring orbit, was a thumbnail sketch rendered in cerulean blue against the cheek of Jupiter. It looked peaceful — pretty, ornamental. The faces of the tetrahedron, the junctions of the wormhole itself, were misty, puzzled-looking washes of blue-gold light, a little like windows.

  It was hard to envisage the horrors that lay only subjective hours away on the other side of that spacetime flaw.