Debt of Ages (7 page)

Nor was there anything remarkable about the fact that he had been born on Alpha Centauri A III. "We've known for some time that there was a planet with water and free oxygen at Alpha Centauri," Sarnac explained to him after the introductions were complete. "But since there's no displacement point there . . . uh, are you familiar with displacement points?"

Andreas nodded—up and down for affirmation, Sarnac noted with relief; he'd once tried to communicate with a Bulgarian. "Yes, Tylar has explained the concept to me." He spoke in the fifth-century military Latin that was the only language they had in common. He had acquired it courtesy of the same kind of implant which had, fifteen years before, conferred it on Sarnac. Tylar had decided against cluttering his mind with unnecessary languages like Standard International English. "It accounted for what happened almost three centuries before my time. But continue, Admiral Sarnac."

" 'Robert,' please. Well, until fifteen years ago that was the only means of interstellar travel available to us. Then we acquired the continuous-displacement drive from the Raehaniv . . . uh . . ."

"Yes," Andreas smiled encouragingly. "Tylar explained about them too. And about the drive."

"Then you know it freed us from dependence on displacement points. There's now a thriving infant colony on your planet . . . or what is, or will be, your planet in your reality." Sarnac's head was starting to throb again.

"Yes," Tylar put in. "It will be quite an important place by the twenty-ninth century. We'll have a kind of listening post in the outer system, and it will . . ." He stopped and shook his head in annoyance. "Latin is even more impossible for discussions of time travel than Standard International English, you know—the same lack of several requisite tenses, including 'subjective-past,' which is what I should be using now. I'll have to use past tense. Better still, I'll let you use it, Andreas. Why don't you explain matters to Robert, starting with an overview of your history?"

"I'll try, but as you know I'm no historian." Andreas frowned with concentration as he organized his thoughts. "Tylar has described your history to me, so I know that by the twenty-first century
your
Earth was engaged in interplanetary exploration. We were only up to steam pumps and black powder firearms at that time—sixteen centuries after the Restorer."

"The Restorer?" Sarnac glanced at Artorius, who gave a rueful nod. "So, Tylar, you were right after all. . . ."

"Yes. Instead of messy but technologically fruitful political disunity, Europe got a reunited and expanded Roman Empire which imposed a kind of . . . Byzantine Mandarinism is as good a term as any. It was as deadly to innovation as the restored Chinese Empire in the same era of both timelines. The result was as Andreas has described. Naturally, none of this affected the Korvaash Unity in any way—except that there were no Raehaniv for it to encounter, and no Raehaniv navigational data for it to capture. So its expansion in Earth's direction was somewhat slower in the years before the great realignment of the displacement network. Pardon me, Andreas—do continue."

"Of course we knew nothing of these events beyond the Solar System. But in the subsequent five centuries, we mastered the scientific method and began to forge ahead technologically." His voice held a kind of forlorn, defensive pride. Sarnac belatedly understood that he was looking at a man who had been cast, all alone, among strangers whose kindliness only underlined the fact that they wielded powers beyond the dreams of gods. "By the twenty-sixth century," he continued, "we were ready to launch our first interstellar expedition, toward Alpha Centauri."

Tylar's face took on the abstracted expression that, Sarnac had come to realize, meant he was in whatever unimaginable linkage he maintained with his sentient machines. The image of a space vessel appeared in midair above the table around which they sat, although there was no apparent holo projection equipment nor any place for it to be concealed. Sarnac couldn't worry about that as he stared in fascination. It was like what Jules Verne might have visualized had the notion of an STL interstellar ship ever occurred to him.

Tylar seemed to read his thoughts. "Yes. The technology of the alternate Earth developed in ways that were idiosyncratic to say the least, from your standpoint or mine. Those divergences make a fascinating story in themselves."

"It looks big," was all Sarnac could say, even though he had no familiar objects to give a sense of scale.

"Indeed," Tylar affirmed. "It had to be, for it was what those science fiction writers of whom you're so fond called a 'generation ship.' It required a century to reach Alpha Centauri, and one of the things of which its builders were ignorant was cryogenic suspension. Given those builders' capabilities, it was really a technological
tour de force
, and like all such was incredibly expensive. I gather it was at least in part a symbol, carrying with it the prestige of the Empire—which included the Americas and large parts of Africa and Russia as well as all of Europe and the Near East, and was locked in rivalry with its Chinese counterpart."

"Sort of like the mid-twentieth-century space programs," Sarnac opined.

"It was expensive," Andreas acknowledged. "But it turned out to be a better investment than its builders imagined, for it put a small portion of the human race out of reach of what happened twenty-five years into its voyage. That was when the Korvaash ships inexplicably appeared in the outer Solar System and descended on Earth."

"The Realm of Tarzhgul?" Sarnac made it as much a statement as a question.

Tylar nodded. "Remember, the displacement network is the same in both universes. And the Realm arose in the same manner after the disruption of that network put an end to the Unity."

"Yeah," Sarnac grinned crookedly. "Founded by a Korvaash dissident who thought the Unity's problem was that it was being run by a bunch of bleeding-heart liberals. After the displacement points went blooey and his planet found itself cut off from its higher-ups, he and his disciples were in a position to step into the power vacuum. They may have heard, in our universe, the news that something funny was going on at Raehan; but that had nothing important to do with their takeover. It would have happened anyway."

"Precisely," Tylar affirmed. "Later, with no Solar Union to oppose them, the Korvaasha of the Realm expanded slowly along the displacement chains, taking until the twenty-sixth century to reach an Earth that could not hope to resist them."

"The generation ship's occupants could only listen in horror to the broadcasts from Sol," Andreas resumed. "They continued on their predetermined course to Alpha Centauri, constantly expecting the Korvaasha to pursue them using whatever mysterious space drive had brought them to Sol. After all, the Korvaasha must have learned about the expedition after occupying Earth, where it was common knowledge. But even after the ship arrived at Alpha Centauri seventy-five years later, nothing happened."

"Naturally," Tylar interjected. "As in our universe, Alpha Centauri has no displacement points in the current epoch. Clearly, the alternate Realm of Tarzhgul had not discovered the continuous-displacement drive in the twenty-sixth century, and still has not in the twenty-ninth.

"But," he continued somberly, "that is no guarantee for the future. The continuous-displacement drive is merely an application of the same gravitic technology that allows displacement-point transit. No matter how uninventive the Korvaasha of Tarzhgul are, they'll stumble onto it eventually.

And they'll remember the hitherto-inaccessible human colony at Alpha Centauri."

"Even if they never discover it," Artorius interjected, "don't forget the
other
Korvaash successor-state that's come to light in Robert's era. It must also exist in the alternate universe. And
those
Korvaasha are more inventive than they're supposed to be! I may as well tell you, Robert, that they don't have the drive in your time. But with no Pan-Human League to run up against, they're bound to discover it eventually. For all we know, they've already discovered it by Andreas' lifetime and are gradually expanding toward an inevitable meeting with the Realm of Tarzhgul. Whether that meeting results in amalgamation or war makes no difference to Andreas' people. They're living on borrowed time."

Andreas' face gleamed with a sheen of sweat in the simulated sunlight and he licked his lips before continuing. "We didn't know any of this, of course. But for the entire two centuries since the landfall on Chiron—that's what we call the third planet of Alpha Centauri A—our lives have been built around preparation for the eventual arrival of the Korvaasha. Among other things, we've tried to develop a means of faster-than-light travel. But we've never discovered the secret of artificial gravity; that's one of the many ways in which our courses of development have differed since your timeline branched off." He looked around at the other three as though challenging anyone to take exception to that particular phraseology, but no one did. "Our efforts were aimed at translating a ship into a parallel space in which the speed of light was higher, or ignorable altogether."

"Oho!" Sarnac smiled. "The old 'hyperspace' idea. It was a favorite with Terran science-fiction writers before the discovery of displacement points."

"The Chironites were wrong about faster-than-light travel," Tylar said. "But in pursuing their erroneous theory they blundered onto something concerning which not even my people have ever had an inkling: the ability to access an alternate reality. Tell him what happened, Andreas."

"Theory predicted that our experimental drive would not work deep in a gravity well, so the experiments were carried on in the outer reaches of the Alpha Centauri system. At last a robot probe was launched—with apparent success, for it vanished and later reappeared on schedule at the same location. But its recorded data showed that it had emerged in exactly the same spot in the outer Alpha Centauri system! But not the
same
Alpha Centauri system, for all the regular communications channels were dead. Instead, there was an enormous volume of incomprehensible broadcasts from Chiron."

Lirauva
, Sarnac mentally corrected him.
That's what we call Alpha Centauri A III, because Varien hle'Morna's daughter Aelanni named it that when she used it as her base for studying twenty-first-century Earth, back in the days when Alpha Centauri had a displacement point. Nowadays, being a nice place and just a short continuous-displacement hop from Sol, it's a rapidly growing colony. What will it be like in the twenty-ninth century?

"At first we thought we had inadvertently discovered time travel," Andreas was saying. "But the probe's photographic record showed absolutely no difference in the relative positions of the stars. Only one conclusion was possible: our probe had travelled not up or down the timestream but
across
to the same point of a different timestream."

"A conclusion that showed great intellectual courage and flexibility," Tylar approved.

"I suppose becoming hidebound is one of the many luxuries we've never been able to afford. At any rate, the video broadcasts the probe had picked up showed that the inhabitants of Chiron—the
other
Chiron—were human. Their language was indecipherable, although one of our more eccentric philologists claimed to discern, in part of the vocabulary, a remote kinship with the languages spoken by the barbarians of northwest Europe before their final incorporation into the Empire. Of more immediate concern was the fact that they possessed technology beyond our utmost horizons. We resolved to contact them and seek their help against the Korvaasha, perhaps enlisting their aid in liberating Earth.

"The energy cost of the transtemporal breakthrough is enormous, and the generating machinery is almost prohibitively massive relative to the payload. It was out of the question to send more than one emissary, especially given the tonnage of life-support equipment he'd need for the voyage insystem to Chiron . . . or whatever you call it. The competition for that posting was fierce, despite the danger; we had no way of knowing for certain that a living organism could survive the transposition. Senior government officials were generally too old or otherwise disqualified. So they turned to those of us who had been in training for the projected faster-than-light interstellar expeditions. In the end, I was selected for good physical and mental health, lack of ties to my own world—I have no living relatives—and broad-based scientific knowledge.
Not
for historical expertise, as Tylar can attest!

"As it turned out, I successfully made the transit and emerged into your reality. Then, just after I had set a course for Chiron, I was met by a ship which made even the technology of the alternate Chiron seem primitive."

"You," Sarnac stated flatly to Tylar.

"Yes. The emergence of the unmanned probe had set up a kind of dimensional fluctuation which our listening post could not fail to detect. The energy flux was quite unprecedented; we had no idea what was happening. So I was sent for. We were fully prepared for Andreas' appearance. We couldn't allow him to contact the twenty-ninth-century inhabitants of Lirauva, of course; our own history said nothing about any such contact. It was clearly a case where intervention was required to keep history on its proper course—the course that eventuates in
us
. So we picked him up."

"I can imagine that scene," Sarnac remarked. He really could. (
"Oh I'm
so
sorry about this dreadful mixup, my dear fellow. . . .
)

"It soon became clear what had happened," Tylar continued, oblivious, "as incredible as it all seemed. The next step, of course, was to determine the exact point at which the two histories had diverged. Andreas, as he has admitted, is no historian. But he has an educated man's familiarity with the salient events and personalities. He knew that in the late fifth century the Roman Empire was being reunified. And he knew who had done it."

"Yes," Andreas said. "The man who bestrides the ages. When I met
him
 . . ." He gazed across the table at Artorius. "Of course, I know that he isn't really Artorius Augustus the Restorer, that in your history he died—or was supposed to have died—at the same time he was winning the Battle of Bourges in mine. But still . . . do you know I was born in a city on Chiron called 'Artoriopolis'?" Artorius gave a gesture that was all offhand graciousness, while Sarnac tried to imagine meeting a George Washington who had been hanged by Lord North and lived on in legend.