Luru Parz said to Torec, “So you have codified Pirius’s time-hopping technique.”
“Yes, ma’am.”
“Describe your algorithm.”
Torec took a breath. Despite the way she had hammered away at her techs to get them to talk to her comprehensibly, the theory of the CTC software was still her weakest point. “We give the system a problem to solve, in the case of our prototype to find a particular protein geometry. And we give it a brute-force way to solve the problem. In the case of protein folding, we instruct the processor simply to start searching through all possible protein geometries. And we have a
time register,
a special cache that stores a flag if a signal has been received from the future.
“The basic CTC program has three steps. When the processor starts, the first step is to check the time register. If a signal has been received—if the solution to the problem is already in memory—then stop. If not, we go to step two, which says to carry out the calculation by brute force, however long it takes. When the answer is finally derived, we go to step three: go back in time, deliver the solution and mark the time register.”
Luru nodded. “So the timeline is redrafted. In the first draft timeline, the problem is solved by brute force. In the final version of the timeline, the answer is sent back through time to the moment when the question is posed. So it isn’t necessary to run the computation at all.”
“That’s correct.”
Luru sighed. “The joy of time-travel paradoxes. You can get the answer to a problem without needing to work it out! But there must be a good deal more to your design. Your closed-timelike-curves must be pretty short.”
“Actually just milliseconds.”
“Surely you can solve no problem which would take longer to solve than that length of time.”
Torec smiled, her confidence growing. “No. By breaking a problem down into pieces you can solve anything.” She described how the problem was broken up into a hierarchy of nested subcomponents. At the base level were calculations so trivial they could be handled within the processor’s short CTC periods. The answers were passed back in time to become the input for the next run-through, and so on. That way an answer was assembled piece by piece and looped back repeatedly to the zero instant, until the overall problem was resolved. “The technical challenge is actually decomposing the problem in the first place, and controlling the information flow back up the line,” she said.
Luru laughed, an odd, hollow sound. “You’re computing with multiple time loops, and you think
that’s
the only challenge? Ensign, you’re a true pragmatist. . . . I think it’s nearly time.”
Over the glittering, much-patched array of the prototype processor, the bots hovered, utterly motionless against the greater lunar stillness. Behind the prototype, the blank Virtual screen hovered, waiting to display the solution.
The last seconds wore away.
And at zero, the screen filled with a molecular diagram. Just like that, with no time elapsed. It was almost anticlimactic, Torec thought.
There was utter silence on the common loops; nobody moved, none of the techs or the observers from the Navy or the Ministry, not even a bot. But on the screen the diagram whirled, as it was ferociously analyzed for verification. After ten seconds, the screen turned green, and numerical results scrolled over its surface.
Torec didn’t need the details, nor would she have understood them; she just knew what that green color meant. “Lethe,” she whispered. “We did it.”
There was a howling. She turned and saw Commissary Nilis capering barefoot on the surface of the Moon. Some transmission glitch was pixellating his image, and his voice sounded feathery, remote.
But his yell of triumph was echoed by the techs. One of them came sprinting clumsily up the slope to Torec. “It worked!” A burly girl from Earth, she grabbed Torec and tried to kiss her on the lips. It was typically inappropriate earthworm behavior, resulting only in a clash of visors, but Torec let it pass.
The bots descended on the prototype complex, checking its physical integrity. But ironically, Torec knew, there should be little for them to find, for as the processor’s paradoxical operation had worked, there had been no need for the problem to be brute-force solved, and no need even for the little toy ships to chatter back and forth on their FTL hops—in this draft of the timeline anyhow. The curves in time had served their purpose—and had rendered their own existence unnecessary. It was another peculiar advantage of a time-travel computer. If it worked correctly,
it never actually ran at all—
and so it should never wear out. Some of the techs had even debated whether they could get away with the economy of making the processors shoddily, almost at the point of failure—for that failure would never be tested.
The four of them stood in a rough circle: Torec, Luru Parz, Nilis and Pila. Of the four, only Torec was physically present, though they all wore skinsuits, save the stubbornly uncouth Commissary. The light falling on each of the Virtuals came from different unseen sources, subtly different angles, and that, set against the black sky and shining ground of the Moon, added to Torec’s sense of unreality.
Pila said coolly, “The trial was obviously a success.”
“Thank you,” Nilis said. “But it’s more than that.” He waved a hand, and a crude Virtual diagram appeared before him. It was Pirius’s early whiteboard sketch, Torec saw, the asterisk standing for the Prime Radiant, and the obstacles surrounding it marked in red—the FTL foreknowledge symbolized by a bar across the approach path, the superior Xeelee computing and defensive ability a circle around the Radiant. Now Nilis snapped his fingers, and the circle around the asterisk turned green. “Today we have removed one of the three fundamental barriers lying between us and the conquest of the Galaxy. We can outthink the Xeelee, outmaneuver their final defenses!
“But you all understand this prototype is just the beginning, the proof of concept,” he said. “Much more work will be needed to turn this crude, sprawling prototype design into a battle-hardened unit. Now is the time for a fresh tranche of funding to be released.”
“We at the Ministry do understand,” Pila said, with the faintest condescension. “That’s why I’ve been authorized to tell you that, with the successful completion of the trial, the project will continue under the auspices of the Navy. The technology is obviously of strategic potential, and funds for its full development will be made available.” She beamed, as if she were handing out gifts.
Torec quietly clenched a fist. She felt vindicated. But Luru Parz stayed silent.
Nilis stepped forward. His face, pocked by resolution flaws, was working as he tried to maintain his smile. “The Navy? But the CTC processor is just the first step to the greater goal, the strike at the Prime Radiant.”
“Which was only a pipe dream, wasn’t it?” Pila said sweetly. “You still have nothing, not even concepts, for overcoming your remaining obstacles. Commissary, it’s time to stop. The Minister feels he has done his duty in backing you this far, on the basis of your previous accomplishments. You’ve done well! Bask in the glory. Once again you’ve done your duty for the cause of the Third Expansion, and now your garden needs you.”
Nilis laughed. “And you’ll throw this miracle to the Navy? Who will use it to lose even more battles in ever more ingenious ways—oh, you fools, can’t you see what you’re doing?”
Pila flinched, and her face closed up. But her Virtual image shuddered.
In a silent explosion of pixels it burst open, and the slim woman was replaced by the massive form of Minister Gramm. He was without a skinsuit, and grease was smeared on his chin. And he was trembling with rage. “You call me a fool? I am warning you: take the get-out, Commissary. Go home. If you make any more trouble, I will cast you down in the pits of Mercury with this child soldier of yours.”
Nilis trembled too, through anger and fear. But he held his ground.
Luru Parz stepped between the two of them. “Enough.” Her Virtual form grazed Gramm’s, and his belly exploded in a hail of muddy pixels.
Gramm lumbered back. “Stay out of this, Luru Parz.”
“I will not. You may not be able to see the potential here, Minister, but I can. For the first time in three thousand years we may be glimpsing a way to end the relentless friction of this war—end it before it ends us.”
“My verdict is final,” shouted Gramm, eyes bulging.
“No,” Luru Parz said simply. “It isn’t. The project continues.” She held his gaze.
To Torec’s amazement Gramm was the first to back down, a Minister of the Coalition somehow beaten by this small, worn-smooth, mysterious woman. Not for the first time, Torec longed to know the secret of Luru’s power.
Luru turned away. “There is nothing left to do here but detail. We must move to the next stage. We meet in one week. In person, if you don’t mind; these Virtual confrontations are unsatisfactory.”
Torec asked, “Where?”
“Port Sol,” said Luru Parz. And she allowed her Virtual to break up, the pixels fading from view in the bright light of the late lunar morning.
Chapter
16
On Quin Base, after the initial flurry of curiosity died down, Pirius Blue tried to keep his distance from the other cadets. He was too old, too different, too
outside
ever to fit in with these swarming kids.
But, despite his reserve, Pirius became an unlikely favorite of three girls who called themselves Tili One, Tili Two, and Tili Three. They were alike in their slight build, their dark coloring, and their small toothy faces. They were actually triplets, products of the same ovum. That wasn’t terribly uncommon, he learned, if you came from a certain big hatchery on the periphery of this star cluster, where for some reason multiple births were common. “But it makes sense,” Cohl said with her usual sour humor. “This
is
the Quintuplet Cluster. . . .”
The Tili triplets spent almost all their time together. They always seemed to fix it so they worked together during training exercises, and when they were off duty they stayed even closer. Eating, working on their gear, they were always giggling, talking, their three so-similar heads clustered together. They shared one bunk, and when they slept, the three of them tangled up together in a warm heap of limbs and heads. They even made love, in full view of everybody, unembarrassed. But their lovemaking was gentle, very tender, almost presexual, Pirius thought. Of course this was all inappropriate. Family units, even twins and triplets, weren’t supposed to be left together lest the bonds they formed got in the way of loyalty to a wider humanity. But then a lot of what went on here was non-Doctrinal.
Things got complicated when the triplets fixed on Pirius. Apparently they had had some rudiments of flight training, as navigators, before falling foul of the authorities. So they had something in common. When one of them offered to show Pirius how to repair scuffs on his skinsuit or to clean out the algae beds in his backpack, he accepted with good grace.
They seemed to treat him as a big, clumsy pet. He put up with it. Maybe it was because the Tilis so obviously had each other that he felt a bit more secure with them.
There were a couple of times, though, when they tried to entice him into their crowded bed. As they ran their little fingers over his belly and calves, no offer could have seemed more tempting. But he drew back, again fearing he might somehow lose himself. He was also worried about how
old
the triplets were; like the other cadets they seemed very small, very unformed, very young.
But when one of them came alone to his bed—it may have been Tili Two, or possibly Three—he found it impossible to resist. And when he let himself fall among her skin and lips and soft limbs, he found an immense, consoling relief.
He tried to discuss his feelings with This Burden Must Pass.
“I felt like you once,” Burden said. He was lying on his bunk, propped up on his elbow, bare to the waist, facing Pirius. The usual meaningless clamor of the barracks washed over them. Burden said, “I was Navy, too. At first there is just a torrent of faces here. But after a time, you start to understand.”
“You do?”
“Pirius, you feel these little cadets are somehow different from you, don’t you? Not just in experience, in background—something more fundamental. And you know why?
Because it’s true.
”
The stock of embryos hatched out of Quin’s birthing tanks were developed from the genetic stock of the soldiers themselves. Of course: where else was it to come from? Not only that, the military planners tried to ensure that only
successful
soldiers got to breed. This was meant to be an incentive to make you get through your training, to fight, to survive. There were no families in this world, no parental bonds. But something deep in every human being responded even to the abstract knowledge that something of herself would survive this brief life.
Pirius knew about this, of course; it was the same on Arches. But he had never before thought through the implications.
It was selective breeding. And it had been going on, right across the Galaxy, long before the war with the Xeelee had come to full fruition. For nearly twenty thousand years mankind had been breeding itself into a race of child soldiers.
“Look at the Tilis,” murmured Burden. “They could probably crossbreed with anybody in the Galaxy, if they had the chance; we haven’t speciated yet. But their bodies are adapted to low gravity, or no gravity at all.
Their
bones don’t wash away in a flood of imbalanced fluids, the way our earthworm ancestors’ did when they first ventured into space. Their minds have adjusted too; they can think and work in three dimensions. The triplets don’t suffer stress from vertigo, or claustrophobia. They are even immune to radiation, relatively.
“There’s more. Here on Quin, if you survive combat, you breed, but for the genes it’s better yet not to wait, not to take that chance. So the cadets become fertile earlier and earlier, until they are producing eggs and sperm long before their bodies are developed enough to fight. Pirius, the Tilis are about sixteen, I think. But they’ve been fertile since they were ten. Infantry are an extreme case. The attrition rate is horrific; generations are very short here. But the same subtle sculpting has shaped
you,
Pirius. And me. Neither of us is an earthworm.”