Deep Space. Ian Douglas
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off. “I know,” he said instead, with a mild shrug. “I was there, remember?”
Twenty years earlier, Koenig had led Carrier Battlegroup 18 through the Sh’daar Node and emerged within the central core of Omega Centauri T-0.876gy, almost a billion years in the past. The fact that the Confederation military had been able to reach so far back into time appeared to have caught the Sh’daar utterly off-balance, to the point that they’d requested what amounted to a truce rather than risking a temporal war.
And that was what had led Koenig to link with Konstantin. If the Sh’daar were afraid of something, that implied that it could be used as a weapon.
Time travel as a weapon. The obvious possibility, there, was that humans might travel back to some point before T-0.876gy and somehow edit the Sh’daar out of existence. That course, however, carried considerable risks for both sides. The Sh’daar had first interacted with Humankind almost sixty years earlier, in 2367. If that bit of history changed, all recent human history would be rewritten as well—the Battles of Beta Pictoris and Rasalhague, of Hecate and 9 Ceti, the loss of Sturgis’s World, Mufrid, and Osiris, and even relations with other star-faring species—the Agletsch, the H’rulka, the Turusch, and others. How much else might be edited into nonexistence?
With a different history, people alive now—like Koenig—might be dead. But people who’d died during the war with the Sh’daar would be alive, and people never born in Koenig’s universe would also be alive.
Koenig felt an icy, inner shock. Karyn—Karyn Mendelson—would not have died in the high-velocity impactor attack at Mars.
Yes … so very much would be different.
But the change would also run full-boost into that hoary puzzle central to all discussions of time travel: the grandfather paradox.
A man uses time travel to go back and kill his father’s father—or otherwise divert him—so that the man’s father is never born. The man himself is never born … and so cannot go back in time to change the flow of history. But then … granddad lives, the man travels back into time, and on and on, around and around, a paradox without end.
Only in this case, entire civilizations were on the wheel. If CBG-18 succeeded in editing out the Sh’daar, the Sh’daar War would never be fought, CBG-18 would never have found the Sh’daar Node and used it to change the past, so the Sh’daar would live … on and on and …
Karyn Mendelson would be alive …
But Konstantin was speaking to him, dry words within his mind. “The possibility of a serious paradox, of a so-called grandfather paradox, would not be an issue, at least not to human civilization at large.”
“Eh?” Had Konstantin somehow been eavesdropping on his inner thoughts? “Why not?”
“Quantum theory predicts that any change to the flow of time as we experience it would simply result in a branching through to another parallel universe, one of what may be an infinite array of universes where every possible determination and outcome not only may occur, but must occur.”
Koenig was startled. He’d heard that theory, but so far as he knew it was only theory. “Is that proven?”
“Proving it would require experimentation that would eliminate access to the original universe and strand the experimenters in the product of a different causal outcome.”
In other words, the man who went back and killed his grandfather would find himself in a universe where he’d never been born. The universe from which he’d originally come would be forever closed to him, since further attempts at time travel would carry him back and forth only along this new time stream.
And if CBG-18 managed to eliminate the Sh’daar in the remote past, the fleet’s personnel might take comfort in existing in a universe cleansed of that enemy, but they could never go home to the universe and time line from which they’d come. If they were somehow able to return to 2424—and that in itself would be a real problem without the Sh’daar Node time machine—it would be to find a completely different world. Karyn would be alive … and in a relationship with another Alex Koenig, assuming the two had gotten together in a universe without the looming threat of the Sh’daar.
Even so, it was tempting. Karyn … alive …
“You’re saying that it’s all futile,” Koenig said after a moment’s unhappy thought. “If we managed to stop the Sh’daar in the far past, we, the squadron, would find ourselves in a different universe … but this universe, the one we left, would not have been changed at all.”
“Obviously,” Konstantin said, “since it would be necessary to travel through a Sh’daar Node to effect the requisite changes.”
“So far as this universe was concerned, CBG-18 would have just disappeared … and the Sh’daar would still be here.”
“Precisely.”
“So what would be the point?”
“None, really. According to the many-universe hypothesis of quantum physics, all possibilities, all possible outcomes exist, each within its own universe. This would be the case whether you traveled through time or not, and the only witnesses to such change would be you and those traveling with you.”
“It’s not my intent to be some damned time-traveling tourist,” Koenig said, angry. “The point is to stop the Sh’daar … in this universe.”
“Indeed.”
“So my question for you is … is there any way to use time travel—or the threat of time travel—to influence Sh’daar intentions? To make them back off … or to defeat them on a strategic level?”
“That will depend, President Koenig, more on the Sh’daar than on us. We don’t know exactly what it is that the Sh’daar fear … or why they asked for a truce twenty years ago. And if the Endeavor and her escorts were destroyed by Sh’daar action—and I should point out that we do not as yet know that it was the Sh’daar who attacked our survey squadron—we do not know what their current motivations might be.”
That gave Koenig pause. He’d not thought of this new possibility. “You’re saying the Endeavor might not have been destroyed by the Sh’daar?”
“We know only that there was an attacker,” Konstantin told him, “not who or what that attacker was.”
“But the Sh’daar … damn it, Konstantin. Who else could it be?”
“President Koenig, you humans must learn to take the longer and larger view, and not assume that all of the cosmos centers on your small experience. There are something on the order of 50 million species in this galaxy alone that humans would probably recognize as intelligent. We know of two that are so highly advanced that humans would be justified in thinking of them as quite literally godlike—the ur-Sh’daar and the Starborn.”
Koenig considered this. Little was known about either culture. What little information they did have had been acquired by a fighter pilot twenty years ago—“Sandy” Gray—during a mind-to-mind encounter with the Sh’daar.
The ur-Sh’daar—the prefix ur was from the German, and carried the meaning of “original,” “primitive,” or “proto.” According to Gray, during his intelligence debriefing, the ur-Sh’daar had been a multispecies interstellar culture occupying a small galaxy—Gray’s Sh’daar source had called it the N’gai Cloud—that possibly had been ejected from the Andromedan galaxy during a collision billions of years before. That cloud eventually had been captured and devoured by the Milky Way, and all that was left of it now was the star cluster known as Omega Centauri.
At some point close to a billion years ago, before Omega Centauri was absorbed by the far larger spiral of the Milky Way galaxy, the ur-Sh’daar had entered something known as the Technological Singularity. In brief, their technological prowess had advanced