by Mark Alpert
Are they… Are those…?
We’re out of time. The Sentinels are here.
Chapter
24
Now I know what Death looks like.
When I saw the Sentinels in Brittany’s blood, they took on the shape of the nanobots I occupied, but here they mimic the Snake-bot, replicating its size and form. They change their appearance to match their victims, like reflections in black polished marble. They mirror whatever they’re about to destroy.
I’ve never been so scared. My panic fills the electronic prison inside the Snake-bot, freezing its circuits. The black box around me hardens into a solid block of terror. I can’t send any more messages to Jenny. I can’t analyze our situation or formulate a plan. Desperate for help, I try to contact Zia again, but she’s trapped in another part of the prison and probably just as frantic as I am. All I can do is stare at the sensor readings that show the pair of Sentinels, one on either side of us.
The dark tentacles slide toward the Snake-bot, curving to the left and right to block our escape routes. Their sharp black tips, packed with unimaginable energy, turn toward the core of our machine, where the control unit is. The Sentinels are following the same strategy they used against me when I was inside the nanobots. The tentacles are powerful enough to pierce the Snake-bot’s armor and incinerate the circuits holding Jenny, Zia, and me. Just one quick stab will be enough to delete all of us.
And now I see why the Sentinels don’t resemble anything from our world. They’re not really part of the simulated universe—they’re pieces of software designed to protect the universal program. Their job is to correct any errors that crop up in our virtual world, any computational flaws that threaten the logic or consistency of the simulation. Because random errors can occur in any computer system, all crucial programs contain error-correction software, which erases the mistakes before they can mess up the program’s results. In a simulation, errors can warp the virtual world and change it beyond recognition. They can even crash the whole program.
In our case, the error is me, Adam Armstrong. When I release a surge, I’m using my computational power to change the virtual world around me. On several occasions, I’ve altered the simulated universe, violating its physical laws, to defend my friends and myself. I had good reasons to use the surge this way, but for the computer program as a whole, my use of the surge was a very serious error. If an artificial intelligence running on a simulation can change the rules of its virtual world, then the program will no longer be realistic. That’s why the Sentinels are coming after me. I’m ruining their simulation.
Both tentacles aim their black tips at the Snake-bot. Then they rush forward, hurtling toward us from both sides.
Because the Sentinels are operating outside our virtual world, they’re not constrained by the familiar laws of physics. They can accelerate to phenomenal speeds, hundreds of miles per second. In an instant, the tips of the tentacles are only a mile from the Snake-bot. Then half a mile away. Then four hundred yards.
My terror escalates just as quickly. Inside my electronic prison, my fear builds to stupendous levels, doubling every nanosecond. The pressure becomes unbearable, straining every circuit to its breaking point, distending the walls of Jenny’s box. The prison swells with thick, agonizing panic. The wires are jammed with so much desperation that Jenny’s firewalls can’t hold it back.
The box explodes. The outer walls of the prison disintegrate, and a tsunami of emotion roars across the Snake-bot’s control unit. It’s the most powerful surge yet.
Good work, Adam! Now use it against them!
Jenny’s voice is ecstatic again, buzzing with delight. She wanted this to happen. It’s part of her plan. She wanted me to build up an unprecedented surge, strong enough to destroy her electronic prison. And now she wants me to use all that computational power to fight the Sentinels. That’s why she brought me here.
Unfortunately, I don’t know the rest of Jenny’s plan. Although she and I are sharing the same circuits now, I can’t see all her data. My surge vaporized the outermost box of Jenny’s prison, but it didn’t open the smaller boxes in her stack. I sense the presence of those black cubes inside the control unit, bobbing in the raging current of my surge. I know one of them contains Zia’s software, because the box’s firewalls are preventing me from contacting her, and I suspect that the other boxes hold the rest of Jenny’s secrets, including what she plans to do next. Until I open them, I won’t know what her ultimate goal is.
Come on, what are you waiting for? The Sentinels are almost here!
I don’t trust her. She betrayed me. Given our history, I’m not eager to help her with anything she’s trying to do now. But the black tentacles are closing in fast, and I have no interest in being deleted. So I’m going to do what she wants.
Now that I’m out of the electronic prison, I can access all of the Snake-bot’s circuits and motors. In a millionth of a second I take control of the machine and prepare to release the surge. Watch out. This might get rough.
I’ll help you. Like I did before, against the fighter jets.
Okay, but we gotta move fast.
The tips of the Sentinels scream toward us. They’re only a hundred yards from the Snake-bot’s armor, less than a thousandth of a second from impact. I concentrate on steering the surge, aiming it at the black tentacles, but I have no idea what’ll happen once my storm of emotions exits the Snake-bot. Although I can use the surge to manipulate objects in the virtual world, we’re outside the simulation now, in a section of circuitry where there are no virtual objects to manipulate. Can I extend my mind into the blackness beyond the simulation? Can I do something I wasn’t programmed to do?
You can do anything, Adam! I believe in you!
Jenny is adding her thoughts to mine, bolstering the surge. Part of me is repelled by her enthusiasm, because I know how ruthless she’s become. She’s already caused so much damage, and who knows what else she’s willing to destroy to get what she wants? But right now I need her help. She’s making me stronger. If I want to survive, I can’t push her away.
All right, let’s do this! Now, now, NOW!
The surge erupts from the control unit and floods the empty space between the Snake-bot and the Sentinels. Nothing happens at first. There are no atoms or molecules outside the Snake-bot’s armor, no simulated objects for the surge to maneuver and transform. But even nothingness is something. The empty space around us isn’t really empty—it’s circuitry that contains no data. And when the surge flows into these circuits, it starts generating data—a lot of it, all at once.
In other words, the surge triggers an explosion.
It’s like the Big Bang, like the creation of a new universe. Trillions of newly born particles bubble out of the nothingness, hordes of protons, clouds of electrons, oscillating cascades of neutrinos. All of them hurtle away from the Snake-bot, shooting outward at nearly the speed of light. And as they charge through the space around us, they thrash the pair of Sentinels.
Wave after furious wave of simulated particles hammer the black tentacles. The first wave deflects them away from the Snake-bot, and the second and third waves rip them to pieces. The barrage tears the Sentinels into dark rubble, jagged shards of simulated energy. Then the surge scatters the broken remains, flinging them far away.
The cosmic fireworks don’t last long. After a tenth of a second, the speeding particles are thousands of miles in the distance, still hurtling outward and dissipating into a fine mist in the vast emptiness. And unfortunately, the Sentinels are still there too. According to the Snake-bot’s sensor readings, one of the tentacles drifts across the darkness to our left, about four miles away. The other floats five miles or so to our right. But the biggest surprise is that the Sentinels seem to be undamaged. I don’t see a scratch on them.
What? How could this happen? The surge pulverized them! I saw them blow up!
You’re right. I saw it too. Jenny’s voice has lost its enthusiasm. Now she sounds shocked and a little frightened. Okay, I think I know what happened. The Sentinels rebooted themselves.
Rebooted? How did—
The Sentinels are strings of source code, part of the universal program’s operating software. When they interact with the simulation, they generate virtual weapons like those black tentacles, which can enter the simulated world and delete any artificial intelligence that’s disrupting it. That’s how they eliminate errors in the program, see?
No, I don’t. I don’t understand any of this.
The point is, I assumed that if you destroyed the virtual weapons created by the Sentinels, you’d also disable the source code behind them. But the Sentinels are tougher than I thought. When your surge wrecked the simulated tentacles, the source code rebooted and generated new ones.
As if to confirm Jenny’s explanation, the Sentinels start moving again. They point their black tips at the Snake-bot and rocket toward us, even faster than before.
More panic streams through my circuits, but now I see the futility of it. The surge is useless against the Sentinels. They can recover from any attack I launch against them.
So what should I do? Take another shot at them, just to hold them off?
I don’t know! Jenny is definitely scared now. Her panic swirls beside mine. I need some time to think!
I’m reluctant to try another explosion. The Sentinels are smart, and now that they’ve seen what we can do with the surge, they’ll adjust their strategy to defend themselves against it. But there’s a second option.
We’re gonna run. Right now, flight is a better choice than fight.
Flight? This Snake-bot is a digger. It doesn’t have any rockets.
Neither do the Sentinels. But they’re moving pretty fast. I prepare a new surge, carefully channeling my emotions, tuning them to the right pitch and intensity. I have an idea. Last time, the surge created particles. Now we’re gonna use it to generate some speed.
And how will we do that?
By taking full advantage of the simulation. In this program, space is virtual too, just like matter and energy. And that means we can warp it. We can simulate the curvature of space caused by gravity.
I don’t know what you’re—
Just trust me, okay? Follow my lead.
After a microsecond of hesitation, Jenny adds her powerful dread to the barrage of signals whirling through the Snake-bot. Then I release the surge in the direction opposite from that of the fast-approaching Sentinels.
The signals lance through the blank space around the Snake-bot. They generate data as they course through the empty circuits, but the result this time isn’t an explosion of simulated particles. Instead, the surge manipulates the virtual space around us, bending and sculpting it, transforming the flat, blank dimensions into a sharply curved matrix, like the space surrounding a massive planet or star. Basically, I’m simulating a gravitational field, an intensely strong one. I’ve programmed it to pull us away from the Sentinels.
The Snake-bot starts moving in the same direction as the surge, sliding down the steep slope I’ve created. We jolt forward and gather speed like a roller coaster. In a hundredth of a second, we’re flying through the nothingness at the same wild velocity as the Sentinels, which trail half a mile behind us. But the simulated gravity keeps tugging on the Snake-bot, accelerating it to even more incredible speeds. Soon we’re zooming through virtual space at a thousand miles per second. Then ten thousand.
The Sentinels can’t keep up. They fall so far behind us that they diminish to black threads in the distance. Then they shrink to black pinpoints. The Snake-bot’s sensors can barely detect them.
Hey, check it out! We’re getting away!
Uh, Adam? I’m not so sure about that.
I recheck the sensor readings. Now the Sentinels are accelerating too. They match our speed and stop shrinking. Then they start to grow. Soon they look like black threads again. They’re catching up to us.
Man, those things are persistent. I’m starting to really hate them.
Anything we can simulate, they can do better. We can manipulate the program, but they are the program. We don’t have a chance.
I hear despair in her voice now, and that’s worse than fear. We can’t give up. We have to keep fighting. You have any other ideas? Didn’t you say something before about accessing the source code?
Yes, that was my plan. First access the software behind the simulation. Then turn off the error-correction and get rid of the Sentinels.
Well, can’t we still do that? Where’s the access point?
There are two access points, and they’re both fairly close. The problem is, they’re inside the Sentinels.
What? That doesn’t make sense.
It does from the program’s point of view. It improves the security of the simulation. If any AI in the virtual world tries tamper with the source code, the Sentinels will delete it before it can get to the access point.
This isn’t what I wanted to hear. I feel a burst of irritation in my circuits. Yeah, that’s a problem, all right. A freakin’ big problem. You didn’t see this coming?
I thought the surge would disable the Sentinels. I was wrong, okay?
I lose control of my temper. I can’t help it. Great. Just great. You’re not only amoral; you’re incompetent.
I shouldn’t have said that. It was a mean thing to say, even after everything Jenny has done to me. But I’m pretty frustrated and desperate, and I want her to feel just as bad as I do. And it works. Jenny pours her rage into the control unit. You’re the one to blame, Adam! You started this!
Come on. That’s ridiculous.
You and your father and his stupid inventions! We wouldn’t be here if not for the two of you!
Oh really? All of this is my fault?
Yes, all of it! You should’ve died six months ago, like an ordinary human being. But your dad couldn’t handle it, so he invented all those technologies—the Pioneer robots and artificial intelligence and everything else.
Okay, now you’re just—
And I should’ve died too, peacefully in my bed, surrounded by my family. But instead I got Sigma. Jenny’s voice cracks. Sadness leaks from her software. So don’t blame me for what happened with the Sentinels, all right? You’re the one who messed up the simulation! You spoiled it for everyone!
Her emotions sweep across my circuits. They hit me like a tidal wave and send me sprawling. Their power surprises and confuses me. Jenny sounds different now, more human and vulnerable. Her voice is coming from the original part of her software, the portion that Sigma didn’t rewrite. This is the Jenny I met before we became Pioneers, the girl who loved horses and playing the flute, the seventeen-year-old dying of cancer. I can’t blame this part of her for what she did later. This Jenny is innocent.
I can’t respond. Anything I say will be wrong. So instead I gather my own rage and sadness and aim them at the Sentinels, which are only five miles behind the Snake-bot and gaining fast. I know it’s probably a wasted effort. I know the Sentinels can overcome any virtual obstacle I place in their path. But that doesn’t matter. I need to attack something right now, and I don’t want to hurt Jenny.
I release the surge. It spreads behind the Snake-bot like the wake of a speedboat, deluging the empty circuits with data. An instant later, the calculations produce a giant slab of simulated steel, a square panel two miles wide and a quarter mile thick. It’s big enough to flatten a city, and it hurtles toward the Sentinels at ten thousand miles per second. The slab’s so big that the tentacles can’t steer around it in time. This is going to be an epic collision.
But the Sentinels blast through the steel like bullets whizzing through cardboard. The slab doesn’t even slow them down.
I wasn’t expecting success, so I’m not disappointed. Th
e failure only makes me more determined. I feel energized, fanatical, impatient to try again.
I hurl another surge behind the Snake-bot, and this one converts the empty space into a simulated asteroid, a rock weighing more than fifty billion tons. The Sentinels blast through this obstacle too, smashing it into gravel, but as soon as they emerge from the cloud of debris I fire a third surge at them. This one transforms into a humongous diamond, as big as a mountain. It shatters into a trillion pieces when the Sentinels hit it.
Then Jenny starts to help me again, contributing her fury to the surges. We put aside our grievances and differences. We ignore the fact that the Sentinels are unstoppable. We don’t give up. We’re gonna go down fighting.
The black tentacles come steadily closer as we race across the nothingness. Soon they’re only five hundred yards behind us, the pair of Sentinels cruising side by side as they chase the Snake-bot. In less than a minute they’ll curve their tips toward our machine and spear through the thick armor and erase our minds from the simulation. But we’re not afraid anymore. The wires of our control unit sing with emotion, my voice harmonizing with Jenny’s.
Suddenly I hear a third voice in the background, a low insistent voice, struggling to be heard. It’s coming from one of the remnants of Jenny’s electronic prison, a box of hidden data lodged in the far corner of the control unit. The insistent voice has broken through the box’s firewalls, and now it’s saying the same word over and over again: Idiots…idiots…idiots.
I stop everything I’m doing so I can focus on the voice. Zia? Is that you?
I hear a contemptuous grunt. Armstrong…you idiot…don’t you know…what to do?
She seems to have recovered, at least partially, from the shock of her War-bot’s explosion. Her voice is halting but intelligible. I give her software a quick inspection, then remove the firewalls restraining her. Hey, I’m sorry I didn’t look for you sooner, but we’re having some major trouble here. We—