Vacuum Diagrams

by Stephen Baxter

  "They're ships."

  "What?"

  I straightened up from my monitor. "Ships. Millions of ships, sWyman."

  I swung the focus around the sky. I picked out a little family of cylinders, tumbling over each other like baby mice. There was a crumpled sphere not much bigger than the pod; it orbited a treelike structure of branches and sparkling leaves. Beyond that I made out bundles of spheroids and tetrahedra, pencils of rods and wands — my gaze roved over a speckling of shape and color.

  I was at the heart of a hailstorm of ships. They filled the sky, misting into the distance.

  But there was no life, no purposeful movement. It was a desolate place; I felt utterly alone.

  I looked again at the tree-thing. The delicate ship was miles wide. But there were scorch marks on the leaves, and holes in the foliage bigger than cities.

  "sWyman, these are wrecks. All of them."

  A motion at the edge of my vision. I tried to track it. A black, birdlike shape that seemed familiar—

  "Luce, why the junk yard? What's happened here?"

  I thought of a shell of lithium-stained light growing out of this place and blossoming around the curve of the Universe. At its touch flocks of ships would rise like birds from the stars... "sWyman, we're maybe the first to travel here from our Galaxy. But races from further in, closer to this event, have been flooding here from the start. As soon as the lithium-7 light reached them they would come here, to this unique place, hoping as we hope to find new understanding. They've been seeking the lithium treasure for billions of years... and dying here. Let's hope there's still something worth dying for."

  Something was growing out of the speckled mist ahead. It was a flattened sphere of blood-colored haze; starlight twinkled through its substance.

  It was impossible to guess its scale. And it kept growing.

  "sWyman. I think that's another ship. It may not be solid... but I know we're going to hit. Where's my intrasystem drive?"

  "Fifteen billion light years away."

  There was detail in the crimson fog, sparks that chattered around rectangular paths. Now the huge ship shut off half the sky.

  "Lethe." I opaqued the window.

  There was a soft resistance, like a fall into a liquid. Red light played through the pod walls as if they were paper. Sparks jerked through right angles in the air.

  Then it was over. I tried to steady my breath.

  "Why worry, Michael?" sWyman said gently. "We've no power; we're ballistic. If another of those babies runs into us there's not a damn thing we can do about it."

  "It's getting clearer up ahead."

  We dropped out of the mist of ships and shot into a hollow space the size of the Solar System. On the far side was another wall of processed matter — more ships, I found. There was a sphere of smashed-up craft clustering around this place like gaudy moths.

  And the flame at the heart of it all?

  Nothing much. Only a star. But very, very old...

  Once it had been a hundred times the mass of our sun. It had squirted lithium-7 light over the roof of the young cosmos. It had a terrific time. But the good days passed quickly. What we saw before us was a dried-up corpse, showing only by its gravity signature.

  Just an old star... with something in orbit around it.

  I focused my instruments. "That thing's about a foot across," I recorded. "But it masses more than Jupiter..."

  The monstrous thing crawled past the surface of its wizened mother, raising a blood-red tide.

  "So what? A black hole?"

  I shook my head. "The densities are wrong. This is a different ball game, sWyman. That stuff's quagma."

  The largest piece of quagma I'd had to work with before had been smaller than a proton. This was my field, brought within miraculous reach. I stammered observations—

  Things started to happen.

  The quagma thing veered out of orbit and shot towards us. I watched in disbelief. "It's not supposed to do that."

  I felt a tingle as it hurtled past, mere yards from my window. It looked like a lump of cooling charcoal. Its gravity field slapped the pod as if it were a spinning top, and centripetal force threw me against the wall.

  Clinging to the window frame I caught a glimpse of the quagma object whirling away from the pod and neatly returning to its orbit.

  Then a shadow fell across the window.

  "That's shot us full of all sorts of funny stuff," shouted sWyman. "Particles you wouldn't believe, radiation at all wavelengths—"

  I didn't reply. There was a shape hovering out there, a night-dark bird with wings hundreds of miles across.

  "Xeelee," I breathed. "That's what I saw in the ship swarm. The Xeelee are here. That's a nightfighter—"

  sWyman roared in frustration.

  The Xeelee let us have it. I saw the exterior of the window glow cherry-red; gobbets melted and flew away. The Xeelee dipped his wings, once; and he flew away.

  Then the window opaqued.

  Something hit my head in the whirling darkness. The noise, the burning smells, sWyman's yelled complaints — it all faded away.

  "...Damn those Xeelee. I should have known they can beat anything we've got. And of course they would police this lithium beacon. It wouldn't do to let us lesser types get our hands on stuff like this; oh no..."

  I was drifting in a steamy darkness. There was a smell of smoke. I coughed, searched for a coffee globe. "At least the Xeelee attack stopped that damn rotation." sWyman shut up, as if cut off. "What's our status, sWyman?"

  "Nothing that counts is working. Oh, there's enough to let us interpret the quagma encounter... But, Luce, the inseparability packet link is smashed. We can't talk to home." Cradling the cooling globe I probed at my feelings. There was despair, certainly; but over it all I felt an unbearable shame.

  I'd let my life be stolen. And, in the end, it was for nothing.

  sWyman hissed quietly.

  "How's the life support, by the way?" I asked.

  "What life support?"

  I let the globe join the cabin's floating debris and felt my way to the opaqued window. It felt brittle, half-melted. It would stay opaqued forever, I realized.

  "sWyman. Tell me what happened. When that quagma droplet lunged out of its orbit and sprayed us."

  "Yeah. Well, the particles from the quagma burst left tracks like vapor trails in the matter they passed through." I remembered how that invisible shower had prickled. The scars laced everything — the hull, the equipment, even your body. And the tracks weren't random. There was a pattern to them. There was enough left working in here for me to decipher some of the message..."

  I felt my skin crawl. "A message. You're telling me there was information content in the scar patterns?"

  "Yes," said sWyman casually. I guess he'd had time to get used to the idea. "But what we can't do is tell anyone about it."

  I held my breath. "Do you want to tell me?"

  "Yeah..."

  It was less than a second after the Big Bang.

  Already there was life.

  They swarmed through a quagma broth, fighting and loving and dying. The oldest of them told legends of the singularity. The young scoffed, but listened in secret awe.

  But the quagma was cooling. Their life-sustaining fluid was congealing into cold hadrons. Soon, the very superforce which bound their bodies would disintegrate.

  They were thinking beings. Their scientists told them the end of the world, seconds away, would be followed by an eternal cold. There was nothing they could do about it.

  They could not bear to be forgotten.

  So they built... an ark. A melon-sized pod of quagma containing all their understanding. And they set up that unmistakable lithium-7 flare, a sign that someone had been here, at the dawn of time.

  For trillions of seconds the ark waited. At last cold creatures came to see. And the ark began to tell its story.

  I floated there, thinking about it. The scars lacing the pod — even my body
— held as much of the understanding of the quagma creatures as they could give us. If I could have returned home engineers could have dissected the pod, doctors could have studied the tracery of tracks in my flesh; and the patterns they found could have been unscrambled.

  Perhaps we would never decipher it all. Perhaps much of it would be meaningless to us. I didn't know. It didn't matter. For the existence of the ark was itself the quagma datum, the single key fact:

  That they had been here.

  And so the ark serves its purpose.

  sWyman fell silent.

  I drifted away from the buckled walls and began to curl up. There was a band of pain across my chest; the air must be fouling.

  How long since I'd dropped out of Susy-space? Had my four days gone?

  My vision started to break up. I hoped sWyman wouldn't speak again.

  Something scraped the outside of the pod.

  "Luce?" sWyman whispered. "What was that?"

  The scrape went the length of the pod; then came a more solid clang over the mid-section. "I'd say someone's trying to get hold of us."

  "Who, damn it?"

  I pressed my ear to a smooth patch of hull. I heard music, a bass harmonization that rumbled through the skin of the pod.

  "Of course. The Ghosts. They're right on time."

  "No." There was a bray in his voice. "They're too late. Our Susy-drive took the Xeelee by surprise, but if the Ghosts try to get any closer to the quagma you can bet they'll be stopped."

  "But—" I stopped to suck oxygen out of the thick air. "The Ghosts don't need to get any closer. The quagma data is stored in the scarred fabric of the pod itself. So if they take the pod they've won..."

  Then, incredibly, I felt a glimmer of hope. It was like a thread of blue oxygen.

  I tried to think it through. Could I actually live through this?

  To Lethe's waters with it. I'd been a passive observer through this whole thing; now, if I was going to die, at least I could choose how. I began stripping off my scorched coverall. "sWyman, listen to me. Is there a way you can destroy the pod?"

  He was silent for a moment. "Why should I want to?"

  "Just tell me." I was naked. I wadded my clothes behind an equipment box.

  "I could destabilize the fusion torus," he said slowly. "Oh. I get it."

  "I presume the Ghosts have been monitoring us," I said breathlessly. "So they'll know that my flesh, my clothes, the fabric of the pod, contain the information they want.

  "But if the pod's destroyed... if everything except me — even my clothes — has gone... then the Ghosts will have to preserve me. Right? My body will be the only record."

  "It's a massive gamble, Luce. You have to rely on the Ghosts knowing enough about human physiology to keep you alive... but not enough to take you apart for the quagma secrets. So they'd have to return you to Earth, to human care — "

  "I don't perceive too many alternatives." I grabbed the frame of the pod window. "Will you do it?" More scrapes; a judder sideways.

  "It means destroying myself." He sounded scared.

  I wanted to scream. "sWyman, your original is waiting for word of us, safe on Earth. If I get through this I'll tell him what you did."

  He hesitated for five heartbeats.

  Then: "Okay. Keep your mouth open when you jump. Godspeed, Michael—"

  Grasping the frame with both hands I swung my feet at the window. The blistered stuff smashed easily and the fragments rushed away. Escaping air sparkled into ice. Sound sucked away and my ears popped with a wincing pain.

  Snowflakes of air billowed from my open mouth, and gas tore from my bowels.

  I closed my freezing eyes and felt my way around the hull. Then I kicked away as hard as I could.

  I waited five seconds, then risked one last look. The Ghosts' moon ship was a silvered landscape, tilted up to my right. A thick hose snaked up to the ripped-open pod. Chrome spheres clustered around the pod like bacteria over a wound.

  I saw the flash through closed eyelids.

  I tumbled backwards. The pain in my chest passed into a dull acceptance. Those Ghosts would have to move fast.

  A cold smoothness closed around me.

  There was light behind my eyes. I opened them to an airy room. A window to my left. Blue sky. The smell of flowers. A nurse's concerned face over me.

  A human nurse.

  Behind him, a Ghost hovered.

  I tried to speak. "Hello, Wyman."

  A footstep. "How did you know I was here?" His pinched expression made me smile.

  "You're looking a lot older, Wyman, you know that?" My voice was a croak. "Of course you're here. You've been waiting for me to die. But here I am, ready to collect my fee.

  "I expect the doctors will spend the next year scanning me on all wavelengths, mapping out the quagma scars and working out what they mean. I'll be famous." I laughed; my chest hurt. "But we're going to get the treasure, Wyman. A message from another realm of creation.

  "Of course we'll have to share it. Humans and Ghosts... but at least we'll get it.

  "And you'll have to share the profits, won't you? And there's my fee as well. You didn't budget for that, did you, Wyman? I'd guess you're about to become a lot poorer—"

  He walked out, slamming the door.

  "But," I whispered, "we must put the interests of the race first."

  There was a bit of blue sky reflected in the Ghost. I stared at it and waited for sleep to return.

  The burst of human inventiveness characterized by the prototype Susy drive was not sustained. As Wyman foresaw, it was simply too easy for human beings to steal what others had already discovered, rather than develop their own.

  The Susy drive — unstable, expensive, unproven — was abandoned.

  New images formed before my eyes.

  Suddenly I was looking at my own face.

  "Jack, every life has a part, in the great cosmic drama we are forced to act out. Watch, now..."

  Planck Zero

  A.D. 5653

  RECENTLY I'VE BEEN PORING over theoretical physics texts. My friends — those who can still stand to see me, since the Ghosts rebuilt me — can't understand it. Okay, they say, you were almost killed by the Ghosts' Planck Zero experiment. It was terrible. But isn't it all over now? Why brood? Why not walk — or rather, fly — out into the sunshine, and enjoy what's left of your life?

  ...But I have to do this. I need the answer to a specific question.

  Is there any way out of a black hole?

  When I heard of the Ghosts' experiment I made a lot of noise. Eventually their Sink Ambassador agreed to meet me — but they insisted the venue had to be the exposed surface of the Moon. Earth conditions wouldn't have made a damn bit of difference to a Silver Ghost, of course; it was all part of the Ghosts' endless diplomatic gavotte. As chief administrator of the Ghost liaison project, it was my precise job not to find such matters irritating.

  I guess age — and Eve's death — were making it harder for me to stomach the pettiness of interspecies diplomacy.

  Into Lethe with it.

  I rode out on the Sahel Cable, then took a flitter to the Moon. We were to meet outside Copernicus Dome; I suited up and walked out briskly. If the Ambassador had been hoping that my sixty-five years would keep me at home it had another thing coming.

  The Silver Ghosts' Ambassador to the Heat Sink floated a yard off the crisp Lunar regolith; the reflection of Earth was a distorted crescent sliding over its midriff.

  We met without aides, as I'd requested, and spoke on a closed channel.

  I came straight to the point. "Ambassador, I've asked to meet you because we suspect you are conducting unauthorized experiments on quagma material."

  It bobbed up and down, a child's balloon incongruously dispatched to the airless Moon. "Jack, I would like to see evidence to support your allegation."

  I was prepared for that. "I'll download the dossier to you. As soon as I'm satisfied you are being just as honest with me."


  "Perhaps you are speculating. Perhaps this is a — " Pause. " — a shot in the dark? You are trying to extract valuable information from me on the threat of evidence which does not exist."

  I shook my head. "Ambassador, think it over. Your race and mine have contacts at many levels, right down to the one-man traders. Security measures between our species are as porous as human flesh." A charming Ghost simile.

  "Perhaps." Its bobbing evolved into a complex shimmering. "Very well. Jack Raoul, we have grown to know each other, these past decades, and I am aware that you are an honest man... if not always an open one, despite your present posture as an injured party. Therefore I must accept that you have such evidence."

  I felt a surge of satisfaction. "Then you are conducting a covert project."

  "Covert, perhaps, but not intentionally so from our human partners."

  "Oh, really?..." I let it pass. "Then from whom?"

  "The Xeelee."

  I studied the Ambassador with a sneaking admiration. "I'll be impressed if you manage to keep secrets from the Xeelee. How are you doing it?"

  The Ghost began to roll gently. "All in good time, Jack Raoul. We cannot be sure of secure communications, even here."

  "This conversation has served its purpose, then. Our staff can proceed with the details—"

  "But we would not allow the dissemination of any data. Only an inspection tour, at the highest level, would be acceptable."

  "The highest level?"

  "Perhaps you would care to visit the site yourself, Jack Raoul."

  I laughed. "Perhaps... when I find out what the catch is."

  The rolling accelerated. "We know each other too well. Jack, we would have to rebuild you."

  There was no inflection in the artificial voice. The image of Earth rippled across Ghost skin.

  I shivered.

  "Ambassador, just give me one hint. You know I'm an inquisitive man."

  "A hint?"

  "What are you trying to do, with your quagma?"

  The rolling stopped. "You have heard of the Uncertainty Principle..."