By disconnecting the governor, Chapman had taken the truck off-line—which prevented Shiva from detecting it as it came hurtling back. Instead, the laser cannon radar array picked it up. Shiva’s log later showed that the AI had mobilized all of its reasoning capacity to determine that the approaching object was in fact a truck and not a meteor. Then it had searched for a way to gain access to the truck’s power control. It found one—and stopped the truck dead in its tracks.
Chapman would have been killed instantly, the truck torn to pieces by its own inertia. Its fragments, along with Chapman’s body, hurtled toward the temporary crew modules atop East Platform. The kinetic energy of the pieces and its erstwhile human cargo demolished the modules instantly, producing two types of wreckage. The module debris took an elliptical course toward the interior of the ring. The rest—including what had once been Chapman—hurtled toward the black hole. By now, most of the debris had already been transformed into a gaseous ring by Kali and was flowing into the black hole, sweating X-rays as its atomic structure was disrupted by the immense tidal forces.
For now, that was the sum total of what was known about the accident.
“Based on this report, Graham was messing with the speed control,” said Tatsuya.
“That’s not the problem. Shiva would assume mechanical fault in a case like that. He should’ve decelerated the truck gradually. We’ve had a few glitches with the trucks and the bullet, and that’s how Shiva has always handled them. This is the first time he’s behaved like this. Sure, yanking the limiter circuit created a problem, but not with the truck. The problem is how Shiva responded. SecDiv doesn’t have the tools to get to the bottom of this. This is all about Shiva’s reasoning processes.”
“In other words, it’s a job for professionals. Like you guys.”
“You must be joking. SysCon can’t solve this either. This is out of the human realm. First of all, there are way too many lines of inquiry. We’d never work through them all. The only thing we can do is get Sati online as soon as possible so she can find out what went wrong with Shiva.”
“But we should be analyzing the accident, not every branch of Shiva’s reasoning process. It’s not going to be easy, but do we really have to put another AI on it?”
“Sati has to analyze all of Shiva’s processes first to tell us where to start looking. And that’s not all.”
Tatsuya noticed Catherine glancing at the coffeemaker. It hit him that he hadn’t had anything to drink since before the funeral. He’d been thirsty without realizing it. He activated an agent program from his web and ordered the coffeemaker to brew two cups. Their personal mugs were just a few feet away in the wall locker. Tatsuya retrieved them and filled them with coffee from the machine.
“Thanks,” said Catherine. “But listen, Tatsuya—why did you make coffee for me?”
“Because I love you? Okay, I thought you’d be thirsty. No fluids since before the funeral.”
“There. You’ve put your finger on the problem.”
“Which is?”
“The impregnable fortress we have to conquer. The difference between humans and AIs. Humans have a theory of mind. AIs don’t.”
“Are you sure? ‘Thirsty’ equals ‘make coffee.’ Simple logic. Any AI could manage that.”
Catherine took a few moments to frame a reply. “Here’s the problem. I’ll exaggerate a bit to make the point. Have you ever seen Grünewald’s Crucifixion?”
“Sorry, doesn’t ring any bells.”
Catherine downloaded an image of the centuries-old painting to her web. It showed Christ on the cross, limbs twisted in a grotesque posture of agony. “What does this make you think of?”
“Well, he has nails through his palms. Must be painful. That’s about it.”
“Right. That’s your theory of mind. As a human, you experience pain. You have memories of pain. You can create an image of Christ in your mind. You have the same physical structure, so you assume Christ feels pain. So let me ask you: why don’t you assume that the cross is suffering? The same nails that go through Christ’s flesh are penetrating the cross.”
“But the cross doesn’t feel any pain.”
“Really? Have you ever been a cross?”
“Not personally, no.” Tatsuya grinned.
“That’s my point. The cross and the human body have different structures. Maybe the cross does suffer. But we have different structures, so we can’t model its suffering in our minds. ‘Thirsty’ equals ‘something to drink’—that’s knowledge a digital inference engine has no way of learning. It has to be programmed, it doesn’t know. That’s why a theory of mind is so important. AIs don’t have that ability yet.
“AIs use language to reach conclusions, but that doesn’t mean they can learn from every form of human reasoning that can be expressed in language. They can’t access the meaning behind the words. Even if AIs can reason, they still need humans to translate phenomena into words or symbols. Otherwise, as far as the AI is concerned, those phenomena just don’t exist.
“It’s not just that the universe humans and AIs understand is different. The universe we perceive is different. Sati and Shiva were populated by their developers with different sets of axioms. Whatever looks like a logical contradiction to Sati will be the key to the accident. What we have to do is analyze that contradiction. Only humans can find internal contradictions in the axioms that a unique AI has constructed using rules of logic.”
“Cath, shouldn’t we just start from what Graham actually did? He must’ve modified Shiva for a reason. Then he noticed something wrong. That’s got to be the key.”
“Good point. Graham was trying to upgrade the resonance-damping system. Oscillations could snap the ring if they grew strong enough. He told me the current safeguards aren’t ideal.”
“Hold on, that sounds like a major problem.”
“I wouldn’t say it’s major right now. But the data we’re getting isn’t what the model predicts. There are these little discrepancies we can’t account for. Whatever Graham was doing with Shiva, there’s probably a connection. Just before the incident he must’ve noticed something problematic about the changes he made. Whatever it was, I think the problem must be connected to why Shiva reacted the way he did. Still, linking cause and effect isn’t something we humans can do in this case. We need to get Sati online as soon as possible.”
“A famous detective needs a brilliant assistant, right?”
“Just so, Watson.”
2
“THAT’S THE GREAT THING about this station. You can eat rice with chopsticks like a human being.”
Tatsuya and Kurokawa, his deputy station manager, were chatting via web from their respective living quarters in the west and east habitat modules of space station Amphisbaena—a huge, bisymmetrical needle rotating around Ouroboros in the same plane as the ring. The two cylindrical habitat modules extended across the width of the needle near its midpoint, flanking a central utility module. Tatsuya was responsible for overall operations, but he’d delegated oversight of Station West to Kurokawa. The distance between the two modules was eighty kilometers.
Amphisbaena—named for the legendary serpent with a head at each end—rotated like a propeller about its center at precisely 8,120 meters per second to generate downward inertia in the modules. Each tubular structure was a small city that combined residential and work spaces, with each level dedicated to a different function. A cylindrical space ten meters across penetrated the structures from top to bottom; a circular, five-meter compartment traversed the central space like an elevator, giving access to each level. Tatsuya’s office was in this glassed-in cylinder, which allowed him to oversee work with key staff throughout the module. Access from the levels to his office was via a projecting bridge. Three levels of floor-to-ceiling glass made up the central section in Station East, which meant that Tatsuya could observe operations at any point of the compass.
Tatsuya was eating. To avoid having to glance at the device embedded in hi
s wrist, he had routed its display to a flat screen monitor. Tatsuya was busily stirring a bowl of green tea over rice. Seeing him about to tuck in, Kurokawa suddenly looked serious. “It’s nice that we have rice to eat, but don’t eat too much. We don’t have much left.”
Kurokawa disappeared from the monitor, his image replaced by a data plot of declining stores of rice from Amphisbaena Harvest No. 7. Superimposed on the curve was another plot, labeled TATSUYA KAWANISHI’S RICE CONSUMPTION. The plot clearly showed that the supply of rice from the last harvest would be exhausted in another week or so at the current rate.
“Why do you send me this stuff when I’m eating?” grumbled Tatsuya, as he gave his rice another stir. His voice was picked up by his wrist web; at times like this it was a very convenient device.
“Mealtime is the only time for info like this. Should I send it during work hours?”
“I see your point.”
“This station isn’t a farm, it’s a logistics center. We have a limited amount of growing space. It puts a load on the life-support systems too.”
“Yeah, but this is the only AADD station where we can grow rice. I seem to remember that farming was your idea.”
“I wanted to grow vegetables, not rice. And we’re supposed to be sharing. You’re eating more than your share.”
“Are you still holding Harvest No. 6 against me?”
“No. The fact that you ate sixty percent of that harvest is something I got out of my system months ago. Besides, I have all the data if I ever need to refresh my memory.”
Tatsuya’s web chimed and he saw a detailed consumption plot for Harvest No. 6. At times like this, the web was a very inconvenient unit.
TATSUYA AND KUROKAWA had commandeered some unoccupied space in the habitats and started growing rice on the pretext of creating a green zone. Naturally these were not real rice paddies. The plants were grown in trays, a crude hydroponic setup with nutrient solution, high ambient oxygen levels, and macromolecular granules instead of soil.
Their inspiration came when they noticed some of the crew cultivating ornamental plants in pots. Most vegetation required gravity to germinate—in fact, gravity was necessary for them to grow normally at all. As Tatsuya’s office moved along Central Block, he saw plants on each level forming small clusters of green, like miniature forests. Boston ivy vines spread along the inner wall, blocking part of the view through the glass. The habitat was an ideal environment for vegetation. It was probably only a matter of time before this castle of high-impact glass and hybrid materials was completely covered with a lush blanket of ivy, as Tatsuya could see from the way the vines were creeping further and further into his field of vision.
Once Chandrasekhar Station was complete, Kali’s gravity would make it possible to farm on the shell’s outer surface. There was no gravity on Ouroboros, which was still under construction. Free-fall conditions prevailed. The only other place with “real” gravity in the vicinity was Kali—not the best location for agriculture.
Space Station Amphisbaena was a charcoal-gray needle 1,728 kilometers long. The carbon-fiber nanotubules used in its construction were the same as those used to build the orbital elevator on Mars. Without their web’s image-enhancement circuits, it was very easy to miss the station against the blackness of space. The tips of the needle completed a revolution in just under eleven minutes, with the center of the station tracing its own counterclockwise path around the rim of Ouroboros at 3,680 meters per second. Each tip of the station made a close approach to the surface of the ring approximately every fourteen minutes. As the tip made its closest approach, the relative speed between station and ring fell to nearly zero. From the ring, it looked as if a titanic pillar was descending from directly above, remaining stationary for a few tens of seconds.
During this window of synchronized movement, supplies could be transferred across the gap between the station and any of the platforms on Ouroboros by extending the tip of the station. A transfer from the station to any given platform was possible once every three hours or so.
In stations East and West, forty kilometers from Amphisbaena’s center of rotation, gravity was more or less the same as on the surface of Mars. Many of Tatsuya’s team members had been born on Mars, making the station a comfortable environment for them. The next closest place a person could eat tea over rice with chopsticks was ten-odd astronomical units away. Trying it in free fall would get a bit messy.
The gravity generated at the tips of the station was far greater than in the habitats. The station had an automated cargo-handling deck at each tip, echoing its two-headed namesake. An unmanned cargo container could enter one of the decks and be transported with the station’s revolution to a platform on the ring. The cargo decks could also be used to pick up containers from one platform and drop them at another. A logistics module running the width of the needle through its center was the hub of the system.
Humanity had been living in space for several generations, but the history of that settlement was still limited. Chandrasekhar Station had been named after a Nobel Prize–winning physicist, but there remained a preference for ancient names like Ouroboros and Amphisbaena—perhaps a sign of humanity’s desire to feel that they had planted their feet firmly in space long ago.
“HEY, KUROKAWA—GET THIS.”
Tatsuya had finished his rice and was now holding his tapered chopsticks up horizontally, butted end to end. “It’s Amphisbaena!”
“Stop trying to change the subject and start acting like the head of this station!”
“All right, okay…”
“If you’re finished eating, I’d like to go over the cargo capture schedule.”
Tatsuya cleared away his dishes, somewhat sorry that lunch was over. When he looked up, there was an augmented-reality display board floating in midair a few feet away. He activated an agent program from his web, and the same opaque white rectangle appeared throughout the station where his team was at work.
The board displayed the current positions of Ouroboros, the station, the nearby planets, and an approaching fleet of cargo containers. Kali’s orbit was highly inclined to the ecliptic plane, approaching aphelion. Once Kali reached its furthest point from the Sun, AADD’s goal was to redirect it along a path that would lead to eventual capture by Uranus.
Reducing relative speed with the ring to zero was not the only reason for Amphisbaena’s rotation. It also facilitated the recovery of cargo containers coming from other locations throughout the solar system. Kali was already more than ten astronomical units from the Sun. Because its orbit was highly inclined, the distance to Mars and Jupiter was about the same. But since the speed of the containers varied depending on their origin, speeds had to be equalized by Amphisbaena’s rotation before the containers could be sent on to their destination.
The tips of the station moved at several kilometers per second. With proper timing there was scarcely any need for an approaching cargo container to decelerate before recovery. This meant less propellant to make the journey, even as other navigational elements including angular motion had to be adjusted. Still, the huge inertia of Amphisbaena’s millions of tons of mass acted as a kinetic energy sink for incoming containers.
“The accident on East Platform threw our construction schedule off. I’ve configured a new timeline. Suppliers on Titan and Mars are now working to this schedule.”
There were advantages and disadvantages to sending cargo containers across space. One advantage was that space itself could be used for large volumes of cargo storage. One disadvantage was that emergencies and changes in plan were naturally difficult to accommodate.
To solve this problem, AADD used containers with limited propulsion capability. While the containers coasted on an inertial trajectory after launch, a certain amount of acceleration or deceleration allowed time of arrival to be adjusted for unforeseen problems or changes in plan. Kurokawa’s plan, displayed on the board, detailed a raft of changes in container trajectory speeds.
“
I think this is the optimal strategy, given our present status. What do you think, Chief?” Kurokawa was clearly trying to minimize any impact on the current program, and there were no conspicuous changes in the arrival sequence. “This should let us stick as close as possible to schedule.”
Tatsuya accessed the ring’s computer system via his web to verify the new timeline. The schedule did indeed minimize changes, but this was not what he had in mind. In a few seconds, he formulated an alternative based on different parameters. “Your proposal keeps us close to program, Kurokawa. But under the circumstances it’s not what I’m looking for.”
“I don’t understand.”
“Our logistics strategy is to keep construction going as efficiently as possible, not necessarily to stick to the program. Right now our first priority is to get Sati up and running. That means we’ve got to expedite the materials we need to get that done.”
“How are we going to do that?”
“The other divisions won’t like it, but we’ll have to change their allocations. SysCon has first call on network equipment.” Tatsuya uploaded his plan to the board. First, all equipment on Amphisbaena needed to activate Sati would be offloaded at the next rendezvous with West Platform. The effect of this change would be offset by rejiggering the velocity correction sequence for the containers.
Amphisbaena’s recovery schedule now looked very different. The board used different color densities to indicate relative differences in the correction sequence for each container in the fleet. Some would be parked in orbit around Kali to form a recovery queue, again using space as a temporary staging area. The overall plan was feasible but clearly more complicated than what Kurokawa was proposing.
“But, Chief, why are we prioritizing SysCon’s needs when the schedule is already out of whack because of the accident?”
The Ouroboros Wave Page 2