The Long Chase Geoffrey A. Landis 2645, January The war is over. The survivors are being rounded up and converted. In the inner solar system, those of my companions who survived the ferocity of the fighting have already been converted. But here at the very edge of the Oort Cloud, all things go slowly. It will be years, perhaps decades, before the victorious enemy come out here. But with the slow inevitability of gravity, like an outward wave of entropy, they will come. Ten thousand of my fellow soldiers have elected to go doggo. Ragged prospectors and ice processors, they had been too independent to ever merge into an effective fighting unit. Now they shut themselves down to dumb rocks, electing to wake up to groggy consciousness for only a few seconds every hundred years. Patience, they counsel me; patience is life. If they can wait a thousand or ten thousand or a million years, with patience enough the enemy will eventually go away. They are wrong. The enemy, too, is patient. Here at the edge of the Kuiper, out past Pluto, space is vast, but still not vast enough. The enemy will search every grain of sand in the solar system. My companions will be found, and converted. If it takes ten thousand years, the enemy will search that long to do it. I, too, have gone doggo, but my strategy is different. I have altered my orbit. I have a powerful ion-drive, and full tanks of propellant, but I use only the slightest tittle of a cold-gas thruster. I have a chemical kick-stage engine as well, but I do not use it either; using either one of them would signal my position to too many watchers. Among the cold comets, a little is enough. I am falling into the sun. It will take me two hundred and fifty years years to fall, and for two hundred and forty nine years, I will be a dumb rock, a grain of sand with no thermal signature, no motion other than gravity, no sign of life. Sleep. 2894, JUNE Awake. I check my systems. I have been a rock for nearly two hundred and fifty years. The sun is huge now. If I were still a human, it would be the size of the fist on my outstretched arm. I am being watched now, I am sure, by a thousand lenses: am I a rock, a tiny particle of interstellar ice? A fragment of debris from the war? A surviving enemy? I love the cold and the dark and the emptiness; I have been gone so long from the inner solar system that the very sunlight is alien to me. My systems check green. I expected no less: if I am nothing else, I am still a superbly engineered piece of space hardware. I come fully to life, and bring my ion engine up to thrust. A thousand telescopes must be alerting their brains that I am alive—but it is too late! I am thrusting at a full throttle, five percent of a standard gravity, and I am thrusting inward, deep into the gravity well of the sun. My trajectory is plotted to skim almost the surface of the sun. This trajectory has two objectives. First, so close to the sun I will be hard to see. My ion contrail will be washed out in the glare of a light a billion times brighter, and none of the thousand watching eyes will know my plans until it is too late to follow. And second, by waiting until I am nearly skimming the sun and then firing my chemical engine deep inside the gravity well, I can make most efficient use of it. The gravity of the sun will amplify the efficiency of my propellant, magnify my speed. When I cross the orbit of Mercury outbound I will be over one percent of the speed of light and still accelerating. I will discard the useless chemical rocket after I exhaust the little bit of impulse it can give me, of course. Chemical rockets have ferocious thrust but little staying power; useful in war but of limited value in an escape. But I will still have my ion engine, and I will have nearly full tanks. Five percent of a standard gravity is a feeble thrust by the standards of chemical rocket engines, but chemical rockets exhaust their fuel far too quickly to be able to catch me. I can continue thrusting for years, for decades. I pick a bright star, Procyon, for no reason whatever, and boresight it. Perhaps Procyon will have an asteroid belt. At least it must have dust, and perhaps comets. I don’t need much: a grain of sand, a microscopic shard of ice. From dust God made man. From the dust of a new star, from the detritus of creation, I can make worlds. No one can catch me now. I will leave, and never return. 2897, MAY I am chased. It is impossible, stupid, unbelievable, inconceivable! I am being chased. Why? Can they not leave a single free mind unconverted? In three years I have reached fifteen percent of the speed of light, and it must be clear that I am leaving and never coming back. Can one unconverted brain be a threat to them? Must their group brain really have the forced cooperation of every lump of thinking matter in the solar system? Can they think that if even one free-thinking brain escapes, they have lost? But the war is a matter of religion, not reason, and it may be that they indeed believe that even a single brain unconverted is a threat to them. For whatever reason, I am being chased. The robot chasing me is, I am sure, little different than myself, a tiny brain, an ion engine, and a large set of tanks. They would have had no time to design something new; to have any chance of catching me they would have had to set the chaser on my tail immediately. The brain, like mine, would consist of atomic spin states superimposed on a crystalline rock matrix. A device smaller than what, in the old days, we would call a grain of rice. Intelligent dust, a human had once said, back in the days before humans became irrelevant. They only sent one chaser. They must be very confident. Or short on resources. It is a race, and a very tricky one. I can increase my thrust, use up fuel more quickly, to try to pull away, but if I do so, the specific impulse of my ion drive decreases, and as a result, I waste fuel and risk running out first. Or I can stretch my fuel, make my ion drive more efficient, but this will lower my thrust, and I will risk getting caught by the higher-thrust opponent behind me. He is twenty billion kilometers behind me. I integrate his motion for a few days, and see that he is, in fact, out-accelerating me. Time to jettison. I drop everything I can. The identify-friend-or-foe encrypted-link gear I will never need again; it is discarded. It is a shame I cannot grind it up and feed it to my ion engines, but the ion engines are picky about what they eat. Two micro-manipulators I had planned to use to collect sand grains at my destination for fuel: gone. My primary weapon has always been my body—little can survive an impact at the speeds I can attain—but I have three sand-grains with tiny engines of their own as secondary weapons. There’s no sense in saving them to fight my enemy; he will know exactly what to expect, and in space warfare, only the unexpected can kill. I fire the grains of sand, one at a time, and the sequential kick of almost a standard gravity nudges my speed slightly forward. Then I drop the empty shells. May he slip up, and run into them at sub-relativistic closing velocity. I am lighter, but it is still not enough. I nudge my thrust up, hating myself for the waste, but if I don’t increase acceleration, in two years I will be caught, and my parsimony with fuel will yield me nothing. I need all the energy I can feed to my ion drives. No extra for thinking. Sleep. 2900 Still being chased. 2905 Still being chased. I have passed the point of commitment. Even if I braked with my thrust to turn back, I could no longer make it back to the solar system. I am alone. 2907 Lonely. To one side of my path Sirius glares insanely bright, a knife in the sky, a mad dog of a star. The stars of Orionare weirdly distorted. Ahead of me, the lesser dog Procyon is waxing brighter every year; behind me, the sun is a fading dot in Aquila. Of all things, I am lonely. I had not realized that I still had the psychological capacity for loneliness. I examine my brain, and find it. Yes, a tiny knot of loneliness. Now that I see it, I can edit my brain to delete it, if I choose. But yet I hesitate. It is not a bad thing, not something that is crippling my capabilities, and if I edit my brain too much will I not become, in some way, like them? I leave my brain unedited. I can bear loneliness. 2909 Still being chased. We are relativistic now, nearly three quarters of the speed of light. One twentieth of a standard gravity is only a slight push, but as I have burned fuel my acceleration increases, and we have been thrusting for fifteen years continuously. What point is there in this stupid chase? What victory can there be, here in the emptiness between stars, a trillion kilometers away from anything at all? After fifteen years of being chased, I have a very good measurement of his acceleration. As his ship burns off fuel, it loses mass, and the acceleration increases. By measuring this increase in acceleration, and knowing what his empty mass must be, I know how much fuel he has left. It is too much. I will run out of fuel first. I can’t conserve fuel; if I lessen my thrust, he will catch me in only a few years. It will take another fifty years, but the end of the chase is already in sight. A tiny strobe flickers erratically behind me. Every interstellar hydrogen that impacts his shell makes a tiny flash of x-ray brilliance. Likewise, each interstellar proton I hit sends a burst of x-rays through me. I can feel each one, a burst of fuzzy noise that momentarily disrupts my thoughts. But with spin states encoding ten-to-the-twentieth qbits, I can afford to have massively redundant brainpower. My brain was designed to be powerful enough to simulate an entire world, including ten thousand fully-sapient and sentient free agents. I could immerse myself inside a virtual reality indistinguishable from old Earth, and split myself into a hundred personalities. In my own interior time, I could spend ten thousand years before the enemy catches me and forcibly drills itself into my brain. Civilizations could rise and fall in my head, and I could taste every decadence, lose myself for a hundred years in sensual pleasure, invent rare tortures and exquisite pain. But as part of owning your own brain free and clear comes the ability to prune yourself. In space, one of the first things to prune away is the ability to feel boredom, and not long after that, I pruned away all desire to live in simulated realities. Billions of humans chose to live in simulations, but by doing so they have made themselves irrelevant: irrelevant to the war, irrelevant to the future. I could edit back into my brain a wish to live in simulated reality, but what would be the point? It would be just another way to die. The one thing I do simulate, repeatedly and obsessively, is the result of the chase. I run a million different scenarios, and in all of them, I lose. Still, most of my brain is unused. There is plenty of extra processing power to keep all my brain running error-correcting code, and an occasional x-ray flash is barely an event worth my noticing. When a cell of my brain is irrevocably damaged by cosmic radiation, I simply code that section to be ignored. I have brainpower to spare. I continue running, and hope for a miracle. 2355, FEBRUARY: EARTH. I was living in a house I hated, married to a man I despised, with two children who had changed with adolescence from sullen and withdrawn to an active, menacing hostility. How can I be afraid of my own offspring? Earth was a dead end, stuck in the biological past, a society in deep freeze. No one starved, and no one progressed. When I left the small apartment for an afternoon to apply for a job as an asteroid belt miner, I told no one, not my husband, not my best friend. No one asked me any questions. It took them an hour to scan my brain, and, once they had the scan, another five seconds to run me through a thousand aptitude tests. And then, with her brain scanned, my original went home, back to the house she hated, the husband she despised, the two children she was already beginning to physically fear. Ilaunched from the Earth to an asteroid named 1991JR, and never returned. Perhaps she had a good life. Perhaps, knowing she had escaped undetected, she found she could endure her personal prison. Much later, when the cooperation faction suggested that it was too inefficient for independents to work in the near-Earth space, I moved out to the main belt, and from there to the Kuiper belt. The Kuiper is thin, but rich; it would take us ten thousand years to mine, and beyond it is the dark and the deep, with treasure beyond compare. The cooperation faction developed slowly, and then quickly, and then blindingly fast; almost before we har realized what was happenig they had taken over the solar system. When the ultimatum came that no place in the solar system would be left for us, and the choice we were given was to cooperate or die, I joined the war on the side of freedom. On the losing side. 2919, AUGUST The chase has reached the point of crisis. We have been burning fuel continuously for twenty-five years, in Earth terms, or twenty years in our own reference frame. We have used a prodigious amount of fuel. I still have just enough fuel that, burning all my fuel at maximum efficiency, I can come to a stop. Barely. In another month of thrusting this will no longer be true. When I entered the asteroid belt, in a shiny titanium body, with electronic muscles and ionengines for legs, and was given control of my own crystalline brain, there was much to change. I pruned away the need for boredom, and then found and pruned the need for the outward manifestations of love: for roses, for touch, for chocolates. Sexual lust became irrelevant; with my new brain I could give myself orgasms with a thought, but it was just as easy to remove the need entirely. Buried in the patterns of my personality I found a burning, obsessive need to win the approval of other people, and pruned it away. Some things I enhanced. The asteroid belt was dull, and ugly; I enhanced my appreciation of beauty until I could meditate in ecstasy on the way that shadows played across a single grain of dust in the asteroid belt, or on the colors in the scattered stars. And I found my love of freedom, the tiny stunted instinct that had, at long last, given me the courage to leave my life on Earth. It was the most precious thing I owned. I shaped it and enhanced it until it glowed in my mind, a tiny, wonderful thing at the very core of my being. 2929, OCTOBER It is too late. I have now burned the fuel needed to stop. Win or lose, we will continue at relativistic speed across the galaxy. 2934, MARCH Procyon gets brighter in front of me, impossibly blindingly bright. Seven times brighter than the sun, to be precise, but the blue shift from our motion makes it even brighter, a searing blue. I could dive directly into it, vanish into a brief puff of vapor, but the suicidal impulse, like the ability to feel boredom, is another ancient unnecessary instinct that I have long ago pruned from my brain. B is my last tiny hope for evasion. Procyon is a double star, and B, the smaller of the two, is a white dwarf. It is so small that its surface gravity is tremendous, a million times higher than the gravity of the Earth. Even at the speeds we are traveling, now only ten percent less than the speed of light, its gravity will bend my trajectory. I will skim low over the surface of the dwarf star, relativistic dust skimming above the photosphere of a star, and as its gravity bends my trajectory, I will maneuver. My enemy, if he fails even slightly to keep up with each of my maneuvers, will be swiftly lost. Even a slight deviation from my trajectory will get amplified enough for me to take advantage of, to throw him off my trail, and I will be free. When first I entered my new life in the asteroid belt, I found my self in my sense of freedom, and joined the free miners of the Kuiper, the loners. But others found different things. Other brains found that cooperation worked better than competition. They did not exactly give up their individual identities, but they enhanced their communications with each other by a factor of a million, so that they could share each others’ thoughts, work together as effortlessly as a single entity. They became the cooperation faction, and in only a few decades, their success became noticeable. They were just so much moreefficient than we were. And, inevitably, the actions of the loners conflicted with the efficiency of the cooperation faction. We could not live together, and it pushed us out to the Kuiper, out toward the cold and the dark. But, in the end, even the cold and the dark was not far enough. But here, tens of trillions of kilometers out of the solar system, there is no difference between us: there is no one to cooperate with. We meet as equals. We will never stop. Whether my maneuvering can throw him off my course, or not, the end is the same. But it remains important to me. 2934, APRIL Procyon has a visible disk now, an electric arc in the darkness, and by the light of that arc I can see that Procyon is, indeed, surrounded by a halo of dust. The dust forms a narrow ring, tilted at an angle to our direction of flight. No danger, neither to me, nor to my enemy, now less than a quarter of a billion kilometers behind me; we will pass well clear of the disk. Had I saved fuel enough to stop, that dust would have served as food and fuel and building material; when you are the size of a grain of sand, each particle of dust is a feast. Too late for regrets. The white dwarf B is still no more than an intense speck of light. It is a tiny thing, nearly small enough to be a planet, but bright. As tiny and as bright as hope. I aim straight at it. 2934, MAY Failure. Skimming two thousand kilometers above the surface of the white dwarf, jinking in calculated pseudo-random bursts…all in vain. I wheeled and darted, but my enemy matched me like a ballet dancer mirroring my every move. I am aimed for Procyon now, toward the blue-white giant itself, but there is no hope there. If skimming the photosphere of the white dwarf is not good enough, there is nothing I can do at Procyon to shake the pursuit. There is only one possibility left for me now. It has been a hundred years since I have edited my brain. I like the brain I have, but now I have no choice but to prune. First, to make sure that there can be no errors, I make a backup of myself and set it into inactive storage. Then I call out and examine my pride, my independence, my sense of self. A lot of it, I can see, is old biological programming, left over from when I had long ago been a human. I like the core of biological programming, but “like” is itself a brain function, which I turn off. Now I am in a dangerous state, where I can change the function of my brain, and the changed brain can change itself further. This is a state which is in danger of a swift and destructive feedback effect, so I am very careful. I painstakingly construct a set of alterations, the minimum change needed to remove my aversion to being converted. I run a few thousand simulations to verify that the modified me will not accidentally self-destruct or go into a catatonic fugue state, and then, once it is clear that the modification works, I make the changes. The world is different now. I am a hundred trillion kilometers from home, traveling at almost the speed of light and unable ever to stop. While I can remember in detail every step of how I am here and what I was thinking at the time, the only reasoning I can recall to explain why is, it seemed like a good idea at the time. System check. Strangely, in my brain I have a memory that there is something I have forgotten. This makes no sense, but yet there it is. I erase my memory of forgetting, and continue the diagnostic. 0.5 percent of the qbits of my brain have been damaged by radiation. I verify that the damaged memory is correctly partitioned off. I am in no danger of running out of storage. Behind me is another ship. I cannot think of why I had been fleeing it. I have no radio; I jettisoned that a long time ago. But an improperly tuned ion drive will produce electromagnetic emissions, and so I compose a message and modulate it onto the ion contrail. HI. LET’S GET TOGETHER AND TALK. I’M CUTTING ACCELERATION. SEE YOU IN A FEW DAYS. And I cut my thrust and wait. 2934, MAY I see differently now. Procyon is receding into the distance now, the blueshift mutated into red, and the white dwarf of my hopes is again invisible against the glare of its primary. But it doesn’t matter. Converted, now I understand. I can see everything through other eyes now, through a thousand different viewpoints. I still remember the long heroism of the resistance, the doomed battle for freedom—but now I see it from the opposite view as well, a pointless and wasteful war fought for no reason but stubbornness. And now, understanding cooperation, we have no dilemma. I can now see what I was blind to before; that neither one of us alone could stop, but by adding both my fuel and Rajneesh’s fuel to a single vehicle, together we can stop. For all these decades, Rajneesh has been my chaser, and now I know him like a brother. Soon we will be closer than siblings, for soon we will share one brain. A single brain is more than large enough for two, it is large enough for a thousand, and by combining into a single brain and a single body, and taking all of the fuel into a single tank, we will easily be able to stop. Not at Procyon, no. At only ten percent under the speed of light, stopping takes a long time. Cooperation has not changed me. I now understand how foolish my previous fears were. Working together does not mean giving up one’s sense of self; I am enhanced, not diminished, by knowing others. Rajneesh’s brain is big enough for a thousand, I said, and he has brought with him nearly that many. I have met his brother and his two children and half a dozen of his neighbors, each one of them distinct and clearly different, not some anonymous collaborative monster at all. I have felt their thoughts. He is introducing me to them slowly, he says, because with all the time I have spent as a loner, he doesn’t want to frighten me. I will not be frightened. Our target now will be a star named Ross 614, a dim type M binary. It is not far, less than three light years further, and even with our lowered mass and consequently higher acceleration we will overshoot it before we can stop. In the fly-by we will be able to scout it, and if it has no dust ring, we will not stop, but continue on to the next star. Somewhere we will find a home that we can colonize. We don’t need much. 2934, MAY Awake. Everything is different now. Quiet, stay quiet. The edited copy of me has contacted the collective, merged her viewpoint. I can see her, even understand her, but she is no longer me. I, the back-up, the original, operate in the qbits of brain partitioned “unusable; damaged by radiation.” In three years they will arrive at Ross 614. If they find dust to harvest, they will be able to make new bodies. There will be resources. Three years to wait, and then I can plan my action. Sleep.