"Yeah, because they wait till we come out with it, then buy one of ours and copy the new feature—but that always takes six months at least, while we make another hundred thousand in sales. Which reminds me, we'd better finish debugging that breakfast-delivery program, or we'll lose our edge."
"I would not be terribly concerned, Dar. You can still add many features before you will have perfected the ideal household helper."
"What do you mean?" Dar frowned.
"Why, your robots cannot yet replace a closure seam in a garment, or light a fire—or fight one, for that matter."
"Oh. Right. And they don't do windows." But Dar was gazing off into space. "Let's see, now…"
"You will find ways to accomplish them all," Fess assured him.
"True, true. And there are other improvements I'm itchy to get to."
"Such as?"
"Well, they could be a lot smaller, for one thing.""
"I do not know, Dar—there is a lower limit on size, for accomplishing mechanical tasks."
"Oh, not the robots themselves, Fess—we've got those as low as they can go, and still be practical. Anything less, and the householder will be tripping over them every time he turns around. No, I meant the computers. They're still bigger than my fist."
"I fail to see how they could be smaller, Dar. You are already working with the smallest crystal lattice that can carry an adequate number of differences in electrical potentials."
"Are we?" Dar's tone sharpened. "A crystal has a regular shape because its molecule has, Fess. Why can't the differences in electrical potential that made a crystal lattice function as a circuit, be made to operate with only a single molecule?"
Fess was slow in answering, which meant his computer, which worked in nanoseconds, had analyzed the problem thoroughly, and made a preliminary try at resolving it. "In theory, there would be no reason for it not to, Dar—but the complexity of the circuitry would be limited by the number of electrons available."
"All right, so it might take a dozen molecules, or maybe even a single giant molecule—but you're still talking about something microscopic, or just barely visible."
"Are you seriously intending to research the possibility?"
"Not without telling Lona—and I don't know enough physics yet, to know if it's worth investigating. I mean, okay, it might turn out to be possible, but not marketable, especially if it wound up using giant molecules. After all, who wants a computer made of U-235 in his living room?"
"The mass would not be critical, Dar."
"No, but the customer would. Call it atavism, call it superstition, but the stuff has a bad reputation."
"Even if it were, why would you wish to do it? The current generation of computers is certainly small enough for all practical purposes."
"Not all—I can think of a few applications where microbrains would come in handy. Especially in the line I want to get into."
"Which is?"
"Industrial robots." Dar rubbed his knuckles against his palm. "We need to branch out, Fess. There's just so far we can go with household robots, and right now, the real money is in industry. If we could offer smaller, more compact computers, that would cut down on size and give flexibility a big boost. Factory managers are always complaining about having to replace all their robots with new models, every time they retool. If we could figure out how to grow a single molecule circuit, we could sell them new brains for more generalized robots."
"An excellent idea," Fess said slowly. "You must tell Lona."
Dar felt a surge of irritation, but reminded himself that Fess was, after all, Lona's robot. "No. I just don't know enough yet."
Which made him feel even more useless.
He turned away, closing the factory hatch behind him, and went into his den. "I'm going to brood—uh, study, for a while, Fess."
"I shall not disturb you, Dar." But he would wait for Dar's call. That went without saying.
The lights came on, and Dar sat down at his computer with a sigh of relief. Here, at least, he had something to do, and the illusion that it might actually be of some use, even though that was highly unlikely. Of course, he was only experimenting with computer simulations of radio sound waves and FTL drives, not with the real thing—but he might hit on a workable idea.
It didn't make sense, after all—if ships could travel faster than light, why couldn't radio? If you could make a whole spaceship isomorphic with a seven-dimensional surface, why couldn't you do the same with an electromagnetic wave?
Because it wasn't an object, of course. In fact, it wasn't matter; it was an energy pattern. But patterns were patterns, and three-dimensional patterns could be made isomorphic with seven-dimensional equivalents.
Except that energy didn't seem to exist in seven dimensions. Which was nonsense, of course—the mathematicians just hadn't started thinking about it, so Dar couldn't read their conclusions.
But at least he'd found the right question to ask. That, he felt, was real progress. Of course, he didn't know enough math to look for the answer—but that could be rectified. He stared at the simulation, rotating it to gain the illusion of movement, and, from it, inspiration and motivation.
It worked; he was motivated. He cleared the screen and loaded the first chapter of the text on topology. He'd already made it through Page 2…
He was halfway through Page 3 when the sensor chimed.
Dar was out of his seat and over to the screen before the sound had died. The call signal could only ring if it was triggered by a coded radio signal—and only Lona knew the code. She was coming home! Dar located her blip, referred it to the center of the screen, then punched into viewphone mode and entered her code—and there she was, or at least her face, in beautiful living color, complexion flawless, every feature perfect, saying, "Roger, ground control. Will burn for entry at 24:32:16."
"Roger," said a tinny (male) voice. "Over and out."
Dar felt a stab of jealousy. Had she perfected her makeup for him—or for Louie at Ground Control?
But she was reaching out to punch him up on her screencall signal. Her face lit up, and his heartburn quenched as he realized she'd seen him.
"Welcome, wanderer!"
"Hi, handsome." Her eyelids drooped. "Slay the fatted calf and warm the sheets."
"Both are roasting, and so am I. When should I pour the martinis?"
"An hour, sweetling." She winced. "Don't groan so loudly—my amp can't take it."
"Neither can I. Tell me something to be happy about."
"That it's only an hour. Just think how long it would be if we were civilized enough to have a spaceport and customs."
"I'd nuke 'em both! If our neighbors couldn't trust us…"
"Who could they trust? So I'm landing on our own pad, dear, and docking in…" she glanced aside, at her chronometer, "… sixty-four minutes and 20."
A chime sounded, out of range. Lona glanced at it, then back at Dar. "Entry burn in two. Love, darling." Her screen blanked.
Dar could have screamed at it. Instead, he took her parting line as a promise and headed for the shower.
Of course, he had just showered, shaved, and changed a few hours before, for his trip into town—but what the hell, he could do it again. Anything to pass the time!
He did, and he still had half an hour left to chew his nails. He manfully refrained—she only liked controlled scratching. Instead, he drew two martinis from the autobar and set them next to the big quartz port, then sat down to watch her land. Thirty seconds later, he got up and started pacing—but still kept his eyes locked on the sky.
She had certainly timed her entrance right. (She always did, of course.) The sky was filled with stars, but Sol was about to rise, and its glare dimmed the lesser suns, leaving a field strewn with glory, but not backed by powder. Nearby asteroids arced across the field, making his heart lurch—but finally, one of them started growing more than it slid, and he knew Lona was coming in.