Temporal Wave

“Sandoval, get your ass in gear. We’re not here for your amusement.”

Harry Sandoval stood on the crater rim, and felt his eyes grow wide with astonishment. The crater was at least three miles wide, and a perfect bowl of rocky rubble. The stench of ozone filled the air, and a mid-day heat haze made the far side of the crater shimmer. Two helicopters buzzed around the crater on unknown errands. The scale of the place made him feel tiny and insignificant.

Harry looked at the speaker, a bear of a man with almost no neck, and grinned. “A bit cranky today, aren’t we Kramer?”

Kramer scowled and muttered, “Damn techies.”

Harry jogged to catch up to the other five technicians following Kramer. He knew no one in the group, and didn’t even know why he was here, wherever here was. All he knew was that the other guys were also technicians of various flavors, from geologist to microbiologist.

The sweltering hike down the bowl left Harry sweating profusely. He could feel sunburn frying his exposed skin. After a half hour of picking their way through boulders, they got close enough to the bottom of the bowl to make out an impact site. Excavators were carving out an enormous hole, and huge Caterpillar trucks were hauling away tons of rubble.

Harry turned to Kramer and asked, “What are we doing in this hell-hole? Your team practically abducted me in the middle of the night, flew me god-knows where, and dumped me here in the underworld. Now we’re on a hike, for god’s sake. What could you possibly need me for, and why couldn’t you just drive us in?”

Kramer’s face was a stony mask. “You will each be briefed individually about your responsibilities and duties. All I can tell you is that ground transportation into the crater is reserved for heavy equipment. Come with me.”

Harry and the others followed Kramer to a portable building where a line of men in unadorned uniforms stood at attention. Kramer said, “Each one of these men will call out a name. When your name is called, go with him. He will take you to your supervisor. You will speak only to those others designated by your supervisor.”

Harry was the last to be called by a sullen looking bald man, who handed him an identification badge with his picture on it. “Wear this badge at all times. The green band along the top indicates that you have access to unrestricted areas only, unless you are accompanied by someone with higher access clearance. Follow me please.” The man barely glanced at him as he took him to a large office trailer. Harry said, “So what the hell is in the hole over there. Have you seen it?” The man ignored the question and said, “Go in. Your supervisor is waiting for you.”

Harry sighed, climbed the three steps and entered the trailer. It was all one spotless white room, with three computers on individual desk stations. The air was at least twenty degrees cooler than outside, and he shivered. A woman at the farthest computer was the only other person present, and when she stood his jaw dropped in astonishment. He knew her. They had been friends at MIT, and while he had fantasized about her back in college, it had never developed any further. While not beautiful in the traditional sense, she had an athletic body and a way of carrying herself with head up and shoulders back that bespoke a powerful confidence. It made her simultaneously attractive and intimidating, at least to Harry. His mouth went dry.

She said, “Well, they didn’t waste any time getting you here, Harry. What did they do? Kidnap you?”

“I, uh, yeah, that’s just about right. Jeri, what are you doing here? For that matter, where is here? Why am I here? And what are they excavating out there?”

“Slow down, Harry. We’ll get to all that. It’s nice to see you after all this time. What’s it been, five years?”

She walked over to Harry and wrapped her arms around him. Into his ear she said, “You have no idea how nice it is to have a friendly face around here.”

Harry flapped his arms in the embrace, unsure what to do with them. After a brief hesitation, he tentatively brought his hands to her back.

They parted as if both were unsure what to make of the embrace. Jeri said, “Let me tell you what I know, which isn’t as much as I’d like. I’m hoping you can help us figure it all out. First of all, two weeks ago I was dragged from Lawrence Livermore the same way you were. I don’t know exactly where we are either. Somewhere in New Mexico, based on what I overheard from a geologist. We’re all here to unravel a mystery, and you just might be the key to it all.”

“Me? You’ve got to be kidding me. I’m nothing more than a glorified computer geek. I don’t even have a security clearance.”

“I don’t believe that. I’d bet good money the government has you in a basement somewhere. Anyway, I told them we had a problem, and they asked me for a name. I gave them yours, and here you are. If all you are is an uncleared computer geek, you wouldn’t be here even with my request. This place and everything in it is top secret. Your computer knowledge is just a big bonus along with your other skills.”

“Yeah? So what about me is so special that you can have me abducted?”

She pursed her lips in thought. “I remember a little club you started in college. A cryptography club, as I recall. Cryptography in the old-fashioned sense, of ciphers and such. I remember you had the mathematics faculty in an uproar when you challenged the professors with encoded messages. Unless I miss my guess, you know modern high-bit encryption algorithms too, don’t you?”

Harry said nothing, his face a practiced mask.

“Your silence is all the answer I need, Harry, and it just confirms that I was right to ask for you. Come here.”

She led Harry to the desk in the back, sat at the computer and opened a data screen. Streams of unintelligible characters washed across the monitor in a flood. “Outside at the bottom of that big hole you saw is a device of some sort. No one is sure what it is, but it’s sending this message over and over. I’ve been trying to figure it out, but I’m a physicist, not a cryptographer. That’s why you’re here.”

“Are you telling me there’s an alien ship out there? You’ve got to be kidding me. No one believes that crap.”

“I didn’t say it was alien. Maybe it is, maybe it isn’t. For all I know it could be an inter-dimensional porta-a-potty. If we can figure out what this message is, we may get a better idea.”

Harry hesitated, then said carefully, “There’s a certain software suite I need, and access to a supercomputer if there is an encryption algorithm to crack.”

“I’m told that you have access to everything you need at the second station there.”

He grinned. “How very efficient of you. But before I start, I need to see the device. Can that be arranged?”

“I suppose I could take you out there. Why is that important? The repeating message is all stored on our system here.”

“There are two possible message origins. The first is terrestrial, that is, of human origin. If it is, I can use cryptography methods to analyze the message. The second possibility is that it is of alien origin. In that case it’s probably not a cipher, but instead a plain message in a format we don’t understand. Interpreting an alien message is quite different than cracking a cipher.”

Jeri nodded. “I see. That makes sense. Come on, I’ll show you the device.”

She led Harry back out of the trailer, and the heat shock made him feel faint. He said, “I thought I liked hot weather, but this is ridiculous. It must be over a hundred out here.”

“That’s about right. Believe it or not, it gets down to about fifty at night. I’m not sure which is worse.”

They followed a smoothed-out path to the excavation. To each side was a rocky landscape that, to Harry, looked like ankle breaking territory.

Jeri said, “Harry, can I ask you a personal question?”

“Sure, but I don’t guarantee that I’ll answer it.”

“Do you think I’m attractive?”

Harry slowed and gaped at her. “That’s, ah, the last question I expected.”

“So are you going to answer it?”

“Yes.”

“Yes you’re going to answer it, or yes I’m attractive.”

“Both?”

“Why did you answer like a question?”

“Because I have no idea where you’re going with this. Yes, I do find you attractive Jeri, but you scare me. You always have.”

“I---scare you? Why? I’m no beauty queen. I don’t turn men into quivering incoherent jello.”

“I suppose that depends on the man. I just know what you do to me.”

“Huh. No wonder.”

“No wonder what?”

She grinned. “Never mind. We’re here.”

The edge of the excavation was surrounded by a wooden handrail and red signs that read, “Stop - Authorized Personnel Only. Yellow clearance required in this area. Lower area requires red clearance.” Harry counted ten plainly uniformed guards stationed evenly around the enormous pit. One of them, a stocky man with an assault rifle approached and said, “Sir, ma’am, this is a restricted area.”

Jeri said, “He’s with me,” and held up her badge for inspection. Harry noticed that the color bands on her badge were yellow.

“Very well ma’am, but go no further.” The guard turned and walked away.

Jeri did a sloppy salute at the guard’s retreating back. “What a prick. This place is full of assholes.”

Harry peered down into the pit. “My god, you called it a device. I’d say that was an understatement. That’s alien if you want my opinion.”

“What makes you say that?”

“Do you know what bilateral symmetry is?

“Sure, that’s when an animal or plant mirrors itself across a center plane. Essentially it means mirrored left and right sides. Humans, and a majority of animals on earth, have bilateral symmetry. Why?”

“It’s not just animals. Look around at the stuff we humans make. Cars, airplanes, boats, toilet roll dispensers, whatever. Most have bilateral symmetry. To some extent, it’s a reflection of ourselves. Sentient bilaterally symmetric humans make bilaterally symmetric stuff.”

“Yeah, so what?”

“Look at that device Jeri. It looks like an elongated egg resting on its base, but the sides are not rounded. It has three facetted planes. It has trilateral symmetry, and it’s a good bet it wasn’t made by the hands of man.”

*****

Harry sat hunched at his terminal watching the incomprehensible characters stream across the screen. It had been two days of data manipulation without any progress, and the frustration was making him punchy.

Jeri stepped up behind him, and kneaded his shoulders with strong fingers. “You’ve been staring at that for two days. If you sit like that any longer, you’ll be a cripple.”

Harry leaned his head back and closed his eyes. “Jeri, you’re hired.”

“Don’t get used to it. I’m your boss, remember?”

“Speaking of bosses, who’s running the show here? None of the guards wear any insignia.”

“As best as I can tell the guards are regular army, there are a few spooks, and some pentagon brass. We seem to be led by a triumvirate of the three groups.”

Harry sat bolt upright. “Damn, I should have thought of this before.”

“What? Have you figured it out?”

“No, not exactly. Do you know what bit shifting is?”

“No, tell me.”

“The basic unit of computer memory storage is the byte. A byte is basically a character, like the characters of the alphabet. A byte is made of eight bits, and each bit is a one or a zero. That’s why it’s called a binary system. Bit shifting is a simple encryption algorithm that shifts all eight bits in a byte one or more places to the left or right. It results in each character changing to another character. Bit shifting a message turns it into gibberish, but it can be easily reversed if you know the original process used.”

“And this is a bit-shifted message?”

“Probably not, but it is reminiscent of it.”

Harry selected a menu command, and the screen changed to a mass of random snow. “If we make the assumption of a binary bit system, zeros and ones, this is what it looks like graphically. A lit screen pixel is a one, and a black pixel is a zero.”

“It still looks like nonsense to me.”

“It is, but remember what that device looks like. Instead of our common bilateral symmetry, the device has trilateral symmetry. Where we use a binary system to represent data, they may be using a tri-nary system. Instead of bits, they use---.”

She chuckled, “Tits?”

Harry felt his face flush red. “Ah no, let’s call them trits to avoid any impropriety.”

“By all means, we must avoid impropriety.”

“Of course, there’s no guarantee that I’m right. Give me an hour and I’ll have a simple program that will allow us to view the data in, ti---, I mean trits, and maybe a few higher orders just in case.”

*****

Jeri had nodded off at her computer terminal by the time Harry completed the simple program. He watched her snoring softly for a few moments before nudging her shoulder. “Hey boss lady, you’re setting a bad example for the team.”

She yawned and stretched like a cat. “I’m fried. My problem has me baffled as much as yours, and I’ve been at this for weeks already.”

“What are you working on?”

“The ship out there is surrounded by a force shield of some kind. I’ve never seen anything like it except in sci-fi movies. In the bright sunlight you can’t see it unless you look closely. It looks a lot like a heat shimmer. At night it looks like a faint blue bubble surrounding the device. The military tried to blast their way through, but the shield just bounces everything back. I think they lost several men before they dragged me out here. I can only use remote sensing equipment on it, and the data are contradictory.”

“You know, I’ve been meaning to ask you. If this is so damn important, how come there are only two of us in this building. I came in with a group of five other technicians, but I haven’t seen any of them since I arrived.”

“I think they are limiting their exposure. They’ve separated us into small isolated groups that work on individual tasks, and bring us our meals. It’s definitely not the best way to work toward answers. I could really use some of my Livermore group.”

Harry shrugged. “I guess you’ll just have to make do with me.”

She stood and said, “So, you have something to show me?”

“Yeah, just don’t freak when you see it, okay?”

Harry slumped into the chair at his computer. “Okay, I tried several bit depths on the data stream, starting at three as I mentioned before. In each case I displayed a colored image of the data stream. For instance, in a trinary system, I used red, green and blue to represent three possible states of each screen pixel, and here’s what I got.”

“It doesn’t look like anything to me.”

“That’s because the data is not in a pure trinary system. Since I thought that three was the magic number, I tried powers of three. Here’s what happened when I hit three to the third power, or twenty-seven possible states for each bit.”

The screen went from a muddy mix of colors to horizontal streaks of similar colors.

She said, “That looks promising, doesn’t it? At least it’s a pattern of some sort.”

“Yeah. Even in our binary system, persistent streaks of the same value are not nearly this common.”

“So what is it then?”

“Let me show you. What you see here is a continuous stream of data, wrapped like text to the next row when it reaches the right edge of the screen. Here’s what happens if I adjust the available width of each row to three to the sixth bits across.”

Jeri gasped. “My god---.”

*****

Harry and Jeri crouched behind a utility building. It was one in the morning, and he stumbled with weariness despite his hammering heartbeat. The last few sleepless nights and jet lag were taking their toll. Jeri looked no better, he thought. Dark circles marked her eyes, and she constantly yawned. He peeked around the building, and saw a security guard walk past the top of the makeshift wooden stairway that led down to the device.

Harry whispered in her ear, “Are you sure this is a good idea? Those guards have guns.”

“Yeah, but they won’t shoot. If we’re fast enough we’ll get onto the stairs, and they will have to chase us down. As long as we arrive a few moments ahead of them we’ll have our chance.”

Harry swallowed hard. “Since when did you become a commando?”

She grinned at him. “Since you decoded the message, Harry. If we just give them the answer, we’ll never see what’s inside. After all this work I have no intention of letting that happen. Are you with me?”

“Eye capt’n, I’m with yea.”

“I’ll wait until the nearest guard is halfway to his next station before I start running. Stay low and quiet. Our dark clothes may buy us a bit more time. If they start yelling, don’t stop no matter what. Ready?”

“Ready.”

She peered around the building and held up her hand. She waited several heartbeats, and then ran hunched over toward the stairs. Harry followed right behind her, stepping high to avoid tripping on the rocky terrain. She ducked under the red warning tape at the top of the stair, and dropped from sight. Harry was over the top and had made it down about a dozen steps before he heard a shout from above, and a spotlight turned on them.

A booming voice called out, “You on the stairs. Stop where you are or you will be fired upon.”

They ran, taking the steps three at a time. It was a long way down, and Harry felt sure he would trip on the stairs at any moment. Jeri stumbled ahead of him, but he caught her arm before she fell and they ran on. A thunder of footsteps trailed them down. Harry looked back, and at least a dozen men were on the stairs above them. They reached the bottom after a full minute of running, and ran up to the shimmering force shield. Harry reached out and touched it. It sizzled and popped at his touch, and although it didn’t hurt, it did not allow passage either. The thunder on the stairs was louder, and they could hear unamplified voices shouting at them.

Harry said, “It’s now or never. Just like in the picture.”

They faced the shield side-by-side, holding hands. They each extended their free hand to the side, raised their clasped hands over their heads, and together touched the shield in three places. For a moment nothing happened, but then their hands fell through and they stepped in together. The shield had reintegrated behind them, and the first chasing guard bounced off the shield and was thrown back fifteen feet, knocking down several others like bowling pins.

A man in a gold laced uniform raised a megaphone to his lips, and said, “Doctor Gillespie and Doctor Sandoval, please stop what you are doing and come out. You will not be harmed.”

Jeri smiled at Harry and said, “I told you it would work. Now what?”

“What do you mean, now what? This was your plan. Are you telling me you didn’t think past this point?”

“Of course not, I’m no commando.”

Harry chuckled, “You could have fooled me. Come on; let’s see if we can get into the device.”

*****

As it turned out, getting in was easy. As they approached, a three-sided aperture irised open in the nearest of the three sides, and they stepped through. Jeri stared wide eyed around her, and Harry felt agoraphobic. From outside the device had been only about five meters in diameter, but once inside it appeared to be about the size of a football field. The aperture slid closed behind them, and the illumination level brightened. The space looked like a scenic park with a large expanse of grass, and the sun lit a bright blue sky above their heads. About fifty meters ahead Harry noticed a tall table in the middle of the space, with something about the size of a bowling ball on it.

Harry gestured toward the table, and said, “After you.”

She smirked. “My, how chivalrous of you kind sir, but I insist. You first.”

“Ladies first.”

“Age before beauty.”

“Damn.” Harry took one step and rocketed ahead about twenty-five meters. His foot came down on the grass with a clanking sound like boots on steel. He wobbled on his feet, his vision in conflict with his sense of motion. Turning his head back to Jeri, he said, “Take your steps slowly. The size of this place is an impressive illusion.”

Jeri yelled, “Harry, you sound like you’re right in front of me, but you’re way over there.”

“No need to yell, I’m only a pace in front of you. Take a careful step forward.”

She did so, and was immediately next to Harry again. “Whoa, that’s a bit disorienting, isn’t it?”

“Yeah.” He looked ahead again. “That table appears to be our destination. Let’s take it slow. Half a step this time.” He took her by the hand and together they took a small step ahead. They rocketed ahead again, and found themselves about twelve meters from the table. On it sat a bald human head, sitting upright on some kind of platter.

When it opened its eyes, Jeri screeched. Harry stood immobilized, momentarily unable to form a coherent thought.

In a gravelly voice it said, “Come on, come on. You’ve kept me waiting and my patience does have its limits you know. I don’t bite.”

Jeri tightened her grip on Harry’s hand. “What the hell is that thing?’

Harry’s stomach was in a tight knot, but by force of will he kept his face relaxed. “It looks harmless enough from here. What’s it going to do? Jump off the table and gnaw on our ankles?”

Jeri giggled nervously, and said, “Let’s hope not, my ankles are my best feature.”

Harry smiled with amusement. “I wouldn’t go that far. They have some pretty good competition in that department.”

The gravelly voice cut in, “Oh please, do I have to listen to this inane banter. We have work to do. Get a move on.”

Harry looked at Jeri and tipped his head toward the table. “Shall we?’

“What have we got to lose but our ankles?” She took a tiny step forward, and Harry followed. They found themselves in front of the high table, the head about even with theirs.

*****

The head wasn’t just bald, but ancient looking as well. The mottled skin drooped in bags and pouches, and the jowls flapped as it spoke.

“You may call me Conductor. I know you have a lot of questions, but if you’ll both just listen for a moment we’ll get through this a lot faster. Pay attention, I don’t like to repeat myself.”

Harry asked, “What are you?”

The head rolled its eyes and said, “Don’t make me regret my choice, boy. Now listen up. This device you are in is a space-time portal. I have been sent from the future to get your help. You will accompany me fifty-one years into the future to help stop an event from occurring. For your protection during translation, please step onto the lighted foot-pads to your left. The restraint field there will keep you safe. In addition, this portal uses a space-time stasis field to protect you from most of the distortion effects.”

Harry looked at Jeri, then back at the head. “Why us? Stop what event?”

“Why not you? You are the perfect candidates. In a week’s time you will both otherwise be dead from unrelated accidents, so there is very little chance of time-line corruption. This portal will appear to vaporize with you in it, so there will be minimal residual human or technology paradoxes. We need people with your skills, and a few neural suggestions made sure that you were brought here. Let’s go.”

Jeri said, “Not so fast. You said that we would otherwise die. You’ve changed your recorded history just by bringing us here, so maybe we don’t die in the here and now.”

It said, “Nature abhors a paradox. If the timeline had changed such that you didn’t apparently die in the now, then I would not have been sent for you from the future. But if I wasn’t sent for you, you would have died quite soon and I would have come for you. Since I am in fact here, you will both either die, or seem to by coming with me. Simple.”

Jeri signed, “I always hated temporal mechanics. It’s like a screwed-up thought experiment.”

“How does history say we died?” asked Harry.

“I’m afraid I cannot answer that. Right now the timeline is in flux, like two diverging space-time paths that reconnect further on. All I know is that you die, or appear to die somehow.”

Jeri said, “The crater we’re in puzzles me. If this is truly a space-time portal, then why does it look like a meteor impact crater?”

The Conductor looked at Harry. “Let’s see if wonder-boy here can figure it out.”

Jeri raised an eyebrow to Harry. “Why? How would he know? He’s just a cryptographer.”

The head cackled with laughter. “Dearie, there’s a lot you don’t know about our boy Harry here. How about it Harry, care to enlighten us?”

Harry looked up in thought. “If you’ve been telling us the truth, then I’d say that the space-time point of entry is nearly instantaneous, causing a massive shock wave that generates something similar to an impact crater.”

The head spun around several times, smiling and laughing. “Yes, yes, of course. Good answer.”

Harry said, “Now how about answering my original question, which I notice you have failed to address. What are you?”

The head stopped laughing. “Why I’m---“

Just then another head popped into existence next to the Conductor, this one equally ancient, but female. Long stringy gray hair topped a grandmotherly face. It shrieked, “Shut up. Don’t you dare tell him.”

Jeri said, “Why, and who are you?”

“I’m the Navigator, and this old fart almost caused a paradox.” She turned to the Conductor. “I don’t want to spend any more time unraveling your messes dear. Now get along. I’ll take it from here.”

The old Conductor smirked, and went flying off like a freed balloon farting out its air.

The old woman’s head turned to them. “What a show-boat that old fool is. God knows why I love him. So, are you ready to go?”

“Not quite,” said Harry. “The Conductor mentioned we had to stop something in the future. What is going on in this future of yours that made you come back for us?”

“I can’t tell you about the future until you are there. Can’t risk a paradox, you know. You’ll just have to take it on faith.”

Jeri said, “What makes you think we’ll go with you then?”

“There’s not much I can tell you in the here and now, like I said. Suffice it to say that you are both single with no close family relations, and are way too intelligent for the boring jobs you now hold. Care for a little adventure? I must warn you though – there’s no way back in time for either of you. Living humans can only travel forward in time.”

*****

The Navigator said, “Harry, we need you to warn the personnel outside. When we disappear from this space-time, we will create another shock wave. It won’t be as large as the one that created the crater, but it will have enough force to knock the buildings flat. They will need at least fifteen minutes to evacuate. Please do not give them any specifics about this ship or its capabilities.”

“Do I need a microphone or something?”

The Navigator chuckled. “My how quaint. No, no, my boy, just nod your head and I will transmit your words outside for all to hear.”

Harry thought a moment, then nodded. “Attention all personnel. This is Harry Sandoval. In fifteen minutes this device will create a shockwave that will destroy all buildings in the crater. Anyone remaining at that time will be injured or killed. Please evacuate immediately.”

The Navigator nodded. “That will do just fine, thank you Harry.”

A slight vibration tickled his feet, and he furrowed his brow. “Hey, Navigator, you said you’d give them fifteen minutes.”

“Of course, of course. It’s just that it takes time to bend space-time you know. Plus a bit of noise and light will get them moving if nothing else does. Here, see for yourself.”

The large expanse of sun-lit field disappeared, and Harry found himself looking at the inside of the three-sided portal. Three metallic frames arched overhead, and the floor on which they stood glowed light through large hieroglyphic characters. Between the arches, the skin of the craft became transparent, and they saw the surrounding excavation at the bottom of the crater.

Jeri said, “Look, they’re running up the stairs.”

Harry looked where she was pointing, and saw the team of men that had pursued them into the crater taking the steps two at a time. The sound of helicopter blades spinning up was clearly audible. “Will they get them all out in time?”

The Navigator looked startled by the question. “Of course, dear boy. We have no wish to harm anyone, and we won’t depart until all are out of harm’s way. It’s just that if we didn’t give them a deadline they’d never leave.”

“Am I correct that our arrival in the future will trigger another dangerous shockwave?” asked Harry. “After all, you can’t know who is nearby, can you?”

“It will not be a problem is this case. We have plotted a course through space-time that will return us to normal space one millisecond after our previous departure to fetch you. This will prevent any significant shockwave from occurring.”

One by one the helicopters departed, some returning for more passengers. When at last the sound of chopping helicopter blades faded away, the Navigator said, “Conductor, please prepare for departure.”

The Conductor popped back into existence beside the Navigator. To Harry and Jeri, it said, “Please step into the lighted footpads. We are ready to translate.”

Jeri held out a hand, and Harry grasped it gratefully. Harry said, “Jeri, would you mind if I---.”

Jeri didn’t let him finish his question. She pulled him close, and her lips on his felt warm and soft. A thrill washed through him in a flood, like an unacknowledged craving satisfied a thousand times over. She pulled away, and Harry stood stunned for a moment before opening his eyes. His throat felt constricted as he said, “How did you know?”

“Harry, it was written all over your face. And if you’d been paying attention it was written on mine as well. Now, are you ready?”

“After that, we’d better live through this. Yeah, I’m ready.”

Together they stepped onto the footpads.

*****

Slowly at first, then with greater and greater speed, the arched columns of the ship rotated above them. Light blazed from the arches in dizzying splashes of color. The floor hummed almost painfully under their feet, and the hieroglyphs illuminated to a painful intensity. Tight fear gripped Harry, and he squeezed Jeri’s hand for reassurance. She looked as terrified as he felt, her eyes wild.

The Conductor said, “This is normal. What you are feeling is as bad as it will get inside your protective restraint field. Do not be alarmed. Fifteen seconds to translation.”

“Space-time coordinates confirmed. Initiating translation,” said the Navigator.

The spinning arches reached a blurring speed, so that their splashes of color merged into bright white. Harry closed his eyes and clamped his mouth shut to keep from screaming. Jeri’s powerful grip in his hand was almost painful.”

“Translation commenced.”

To Harry, it felt like jumping out of an airplane. His sense of up and down vanished, to be replaced with vertigo.

A moment later gravity returned with a jolt, and hollow boom echoed off the arches.

“Translation completed,” said the Conductor. “For your safety, please remain where you are until all systems have cycled down.”

Once again, the three inner surfaces of the portal became transparent. Harry and Jeri stared in awe at the landscape outside. The sky was a bright orange from horizon to horizon, and the earth was a muddy brown pocked with enormous impact craters. Wrecked and tilted city buildings, devoid of windows and missing upper floors, dotted the landscape. A wide variety of rusted and overturned cars, trucks, and other vehicles lay piled everywhere. A fine silty sand blew against the portal, making a sound like rain.

Harry turned to the Conductor, his lips in a tight line. “You have some explaining to do. What happened here, and what do you need us for? It looks like it’s too late for us to be able to do anything, and now you’ve marooned us in this apocalyptic future.”

Jeri wrapped her arms around Harry and put her head on his shoulder. His shirt was wet under her cheek.

*****

The Conductor said, “I am sorry to have brought you here under somewhat false pretenses, but it was, and still is, essential to the survival of the human species, in fact, all life on planet earth.”

Jeri turned her head, and said, “False pretenses? What do you mean?”

“I’m afraid that the news of your deaths was not altogether accurate. We could not tell you the true reason because of the possibility of creating a temporal paradox if you’d decided to stay in the past, so we made up the story of your deaths as a lever to get you here. However, once you have heard the true reason, we hope that you will still support your previous decision to come with us.”

Harry felt his face flush with anger. “Take us back, right now.”

“I’m afraid that is not possible. As we told you before, humans cannot travel backward in time. It would kill you. Please be patient a moment and allow me to explain.” The Conductor paused, examined their faces, then continued, “Forty-nine years ago, a small group of physicists performed an experiment to prove string theory. As you know, string theory in your timeframe described ten spatial dimensions plus time, for a total of eleven dimensions. The physicists theorized that many other realms exist, each using three of the ten spatial dimensions and time. They further theorized that if any single spatial dimension was used by different realms, something they termed adjacent realms, it might be possible to travel from one to another. Unfortunately, their experiment succeeded. They created a stable rift to an adjacent realm that held intelligent alien life. That life viewed our incursion as a threat, and responded accordingly. They made the space time portals like the one we are in now, and devastated earth over the ensuing forty-six years. As you can see, there is little life left on earth, and the aliens have begun colonizing.”

Jeri said, “I still don’t see how we can help.”

The Navigator, who had been quiet during the Conductor’s story, said, “Warning, a timeline displacement wave is approaching. Thirty seconds to impact. Jeri and Harry, for your safety please return to the lighted footpads.”

As they stepped into the footpads, Jeri asked, “What is a timeline displacement wave?” Harry noticed the tremor in her voice, and wrapped an arm around her waist.

The Conductor said, “A timeline displacement wave occurs when there is a significant unexpected event in the past that results in a radical change in the timeline from that point on. The original timeline from that event onward becomes a dead-end, and a new timeline branch is created. A timeline displacement wave pushes forward in time from the event, rearranging history to suit the new past event.”

“Ten seconds”, said the Navigator. “Initiating space-time stasis field. Stand by.”

They looked out through the transparent sides of the space-time portal. Harry saw a bright arc of blue sky rip across the orange horizon, which expanded in a rush across the sky toward them. Something was happening on the ground as well, although the low perspective made it difficult to see.

“Five seconds.”

Now Harry could see the ground in the distance changing color from mud brown to green as well. “What is going on?”

The Conductor said, “The timeline is being rewritten.”

The ground appeared to roll like an approaching wave, and a deafening ripping noise made Harry cover his ears. When the ground wave hit, the space-time portal rolled with it, slid a few meters, and came to rest at a slight angle.

Jeri was the first to speak. “My god, Harry, look.”

Harry hadn’t realized that he had closed his eyes until that moment. He opened them, and to his astonishment looked out on an expansive green park with a town or small city nearby. Small hover vehicles sped by overhead, apparently oblivious to the space-time portal.

Harry stomach clenched as realization hit him. He said, “Somehow Jeri and I created Armageddon, didn’t we?”

The Navigator smiled, and Harry had the oddest sensation of familiarity with the old body-less woman. She said, “I’m afraid so. The group of physicists the Conductor described were you and Jeri. Two years after we plucked you out of the timeline, you ran your string theory experiment, and the course of life on earth changed irrevocably. That is, until we intervened and pulled you out of the timeline before that happened.”

Jeri put her hands over her face and sank to her knees, sobbing softly. “We did that? We destroyed the world?”

The Navigator smiled. “And you also saved it.”

“What do you mean?”

“The government kept you and Harry sequestered in a secure facility for many years, as you tried in vain to close the alien time portals. You failed, but when a damaged space-time portal was eventually captured from the enemy, you came up with a new plan.”

The Navigator said, “The space-time stasis field is breaking down. You both must exit immediately.”

Harry asked, “Why is that?”

“You must hurry. You belong in this timeline, but we and this space-time portal do not. In this timeline we never existed. The stasis field is holding us here, but soon the timeline pressure will crush us.”

One of the side panels irised open, and the sweet scent of fresh air wafted in on a light breeze. A shower of sparks fell from the overhead arches, and the hieroglyphs on the floor flared in bright flashes. Harry took Jeri’s hand, and they ran out of the portal into the park. They turned and watched the portal from ten meters away. The Navigator and the Conductor were visible through the opening. Harry and Jeri waved.

Light flared from the edges of the facetted sides, then the portal folded in on itself like a house of mirrors and disappeared from sight with a hollow boom.

*****

Jeri hand gripped his firmly as they walked hand-in-hand across the park toward the city. Harry was lost in his own thoughts about their new future.

Jeri said, “We never found out who they were, the Conductor and the Navigator.”

“I’m pretty sure I know.”

“Yeah? Tell me.”

“Well, the Conductor looked a lot like my grandfather, and the Navigator reminded me of you.”

“That old biddy with the stringy hair reminded you of me? That’s not very flattering you know.”

“Remember when the Navigator said that we saved the world? I think that our future selves made the Conductor and Navigator in our own images, to go back and take us into the future. Who better to convince us to go but ourselves? Who would know us better?”

She looked at Harry with an appraising eye. “Yuck, that’s what you’re going to look like when you’re eighty? Maybe I should change my mind about you right here and now.”

“You were no spring chicken yourself you know.”

She grinned, kissed him firmly on the lips, and changed the subject. “So wonder-boy, what was your job anyway?”