Part of the reason why the affair had gone so well, Ranjit knew, was that the advance planning had been meticulous. Weeks before the attack the two surviving old American aircraft carriers had been loaded up with everything needed for the job, the goods supplied mostly by Russia and China. Fully prepared, they were deployed to the Gulf of Mexico—on “training missions,” the routine Department of Defense announcement said—and in fact ready to start supplying emergency help almost before the echoes of Silent Thunder’s nuclear blasts had died away. Even Myra had to admit that the effects had not been bad.
They were dawdling over a leisurely Sunday breakfast in the garden, just the three of them. Ranjit was checking some lecture possibilities on one screen, Myra idly following the news on another, while Natasha, who was nearing her twelfth birthday, practiced her backstroke in the pool. Then Myra looked up, sighing. “It looks like they’re coming to an agreement,” she told her husband. “Kenya and Egypt, and the other countries that depend on the Nile River water.”
He gave her a comfortable smile. “I thought they would,” he said. He had, in fact, all but guaranteed they would, at a time, no more than six months past, when the two principals had mobilized their not inconsiderable military might and sent the armies to glare at each other. But then the UN Security Council had favored them with one of its strongly worded warnings. “I guess they take the Security Council more seriously now, with Silent Thunder always looming,” Myra ruminated.
Ranjit demonstrated what an intelligent husband he was by omitting any “I told you so.” All he said was, “I’m glad they’re working it out. Listen. What would you think if I said my next seminar would be on the Collatz conjecture?”
Myra looked puzzled. “I don’t think I’ve ever heard of that one.”
“Probably not,” Ranjit agreed. “Most people haven’t. Old Lothar Collatz never got the publicity he was entitled to. Here, I’ll show you.” He turned his screen so that they could both see it. “Take any number—something under three digits; it works with really big ones just as well, but it takes too long. Got the number?”
Myra essayed, “Well, how about, say, eight?”
“Good one. Now divide it by two, and keep on dividing by two until you can’t get a whole-number answer anymore.”
Obediently Myra said, “Eight, four, two, one. Is that what you mean?”
“That is exactly what I mean. Wait a minute while I put it on the screen…. All right. That is what we will call rule number one for Collatz: When it’s an even number, divide it by two and keep on doing that until you don’t have an even number anymore. Now take an odd number.”
“Um…five?”
Ranjit sighed. “All right, we’ll just do the easy ones. So now we apply rule number two. If the number is odd, you multiply it by three and add one.”
“Fifteen…sixteen,” Myra supplied.
“Good. Now you’ve got an even number again, so you go back to rule one. Let me put that on the screen.”
As Ranjit quickly typed eight, four, two, one next to his other numbers, Myra raised her eyebrows. “Huh,” she said. “They look the same.”
Ranjit gave her a large smile. “That’s the point. You take any number, even the largest number you can think of, and work on it with just those two rules. Divide by two if it’s even, multiply by three and add one if it’s odd, and you’ll come down to one as a result every time. Even if the numbers you start with are pretty big—wait, I’ll show you.”
He typed some programming instructions onto the screen and gave it the number twenty-seven to start with. Alternating rules one and two as directed, the screen displayed “81… 82… 41… 123… 124… 62… 31… 93… 94… 47… 141… 142… 71… 213… 214… 107…” until Ranjit shut it off. “See how the number keeps bouncing up and down? It’s sort of pretty to watch, and sometimes the numbers get really large—there were some people at Carnegie Mellon who got it up to numbers with more than fifty thousand digits—but in the long run it always collapses to one.”
“Well,” Myra said comfortably, “sure it does. Why wouldn’t it?”
Ranjit gave her a hot look. “We mathematicians don’t deal in the intuitively obvious. We want proof! And back in 1937 old Collatz made his conjecture, which is that that will happen to any number at all, all the way up to infinity. But it has never been proved.”
Myra nodded absently. “Sounds like a good possibility.” Then, shading her eyes as she looked toward the pool and raising her voice, she said, “Better take a break, Tashy! You don’t want to get overtired.”
Ranjit was quick to meet his daughter with a towel, but he was looking at his wife. Finally he said, “Myra? You sound a little bit distracted. Is anything wrong?”
She gave him a fond look, and then a real laugh. “Wrong? Not at all, Ranj. It’s just that—Well, I haven’t seen the doctor yet, but I’m pretty sure. I think I’m pregnant again.”
31
SKYHOOK DAYS
For Myra de Soyza Subramanian, caring for her second infant was even more of a breeze than caring for her first. Her husband, for example, did not now come home depressed from a job he thought irrelevant; his students liked him, he liked his students, and Dr. Davoodbhoy was unfailingly pleased. The outside world was easier to take now, too. Oh, a few nations could not seem to break the habit of making threatening noises at their neighbors. Hardly anyone was actually getting killed, though.
And, over Beatrix Vorhulst’s protest, they had finally moved into their own little house—“little” only by comparison with the Vorhulst mansion—just steps from one of the island’s beautiful broad beaches, where the water was as warm and welcoming as ever. By the time they were settled in their new house, the world outside no longer seemed as threatening. Little Robert splashed in the shallowest part of the pool, while Natasha found deeper water to demonstrate her considerable (and, Ranjit maintained, clearly inherited) skill at swimming—or any other way—when she wasn’t taking sailing lessons from a neighbor who owned a little Sunfish. What made being in their own home particularly pleasant was that Mevrouw Vorhulst had parted with her favorite cook and Natasha’s favorite maid to save Myra the trouble of housework.
Another way in which Myra’s second pregnancy was unlike the first went by the name of Natasha—well, more often it was Tashy. Tashy wasn’t a problem. When she wasn’t winning ribbons for swimming—only in children’s events so far, but she was seen to watch adult races with narrowed eyes and obvious intentions—she was busy at being her mother’s assistant, deputy, and sous-chef. Thus aided, Myra had a gratifying number of hours each day to spend catching up on what was going on in the field of artificial intelligence and autonomous prostheses.
That was quite a lot. By the time Myra had begun to evaluate each muscle twinge in the hope that it might be the beginnings of labor, she was pretty nearly up to speed again.
Of course, that wouldn’t last. By the time the new baby was birthed, weaned, toilet trained, and off to school, Myra would have slipped behind her cohort again. That was inevitable.
Was Myra angry at this tyrannical law of childbearing? It was clearly unjust. It dictated that any woman who wanted a baby had to accept Mother Nature’s inflexible decree that, for a period of time, the cognitive functions of her mind would have to take second place to mothering. It would have to be a fairly significant period, too. Ten years was the accepted minimum before a female AI nerd (or medical doctor or politician or, for that matter, pastry chef) could get back to her career.