2164
Port Shiva, Titania
Thirteen years had passed since
Richard III
had departed for Alpha Centauri. In the years that followed, humanity launched one probe after another toward the nearby stars. By 2164 the total had risen to fifteen.
Each probe was functioning as designed, sending data back to the solar system. Of course, a large portion of this data was routine system status information. But as the images of Alpha Centauri became more detailed, scientists began monitoring the data on a daily basis.
Still, thirteen years is a long time for human beings. Most of the original program participants had been reassigned to other departments and were looking after other projects now, their places taken by new people.
Agnes and Aguri were on a dish-shaped structure twenty meters wide. Benches and vegetation gave the area a gardenlike atmosphere. In the center of the dish was a round, roofless brick structure. The structure contained a number of data-processing devices, most of them embedded in the walls.
The dish hung suspended from a dawn redwood, the trees having been incorporated into the structure of Port Shiva itself. This particular dish was one of the control points for the interstellar probe program.
Agnes had upgraded the probes since
Richard III
had been launched. There were three generations of probes now; the third and newest sported a more efficient matter-antimatter propulsion system and was faster than the previous generations. Because of this, data from second-generation probe
Desdemona,
bound for Epsilon Eridani, would reach Agnes later than data from thirdgeneration probes like
Apemantus
and
Beatris,
launched toward the more distant 61 Cygni and Epsilon Indi.
“Are all fifteen probes telling us this?” asked Agnes.
“No, we’re only getting data from the first ten. The last five
haven’t reached maximum velocity yet.”
“If our five newest probes aren’t traveling fast enough to gather this data, it’s going to be less precise than I hoped. Charon, Triton, and
Shantak II
are corroborating the probe data. But those facilities were built to detect specific phenomena. They’re not broad-spectrum
observation sites.”
“True, they’re not,” Aguri said. “The big interferometers on Charon and Triton look for gravity wave sources by comparing time differentials across data. But the interferometers themselves aren’t specialized. It’s their data-processing infrastructure. They’re doing narrow-band analysis geared to what they’re looking for. But the newest processors can handle a much wider range of frequencies.”
“So you used those processors to go back and review the data to
verify your hypothesis?”
All interstellar probes, beginning with
Richard III,
were equipped with an advanced AI. For the first few years of their missions, the AIs could be monitored and, within limits, upgraded remotely, especially if the AI encountered a problem beyond its capacity.
Richard III
’s AI was upgraded not far from the solar system. The data from each probe was applied to the next, making each one
more “experienced” than the last.
This increasing sophistication had led to an unexpected discovery. The newest probes were capable of accelerating to around thirty percent of light speed. At this speed, starbow effects—relativistic Doppler shifting of starlight—were not yet pronounced. They could only be detected with specialized sensors. Confirmation of the starbow effect was an important goal of all interstellar probes, beginning with
Richard III.
Astronomers hoped that relativistic
Doppler effects would open up new methods of observation.
The ability to upgrade AIs after launch played an important role in the effort to gather starbow data. Now Aguri had discovered that the effect applied to gravity waves as well as electromagnetic waves.
Unfortunately, the need to shield the fast-moving probes against interstellar dust prevented them from serving as long-range laser interferometers. Instead, the probes observed minute frequency shifts in starlight caused by gravity. Careful analysis of the data
confirmed that starbow effects applied to gravity waves.
Aguri had boosted the accuracy of the probes’ sensors by networking them. The results were confirmed by the large interferometer arrays on Triton and Charon and by
Shantak II,
the gravity-wave observation platform half a light-day from the Sun. Collating all this data would eventually lead to new ways of utilizing gravity
waves in astronomical research.
“And this tells you that gravity wave transmissions are going to
other points in the galaxy?” said Agnes.
“That’s what the data suggests. That implies the existence of
nonhuman intelligences.”
“Atwood said the same thing. During the standoff on
Shantak II,
he never stopped observing. He’s completely sold on the idea of
nonhuman civilizations. Has the bug bitten you too?”
“Atwood is a strange bird, but he’s a first-rate scientist. The trouble we had with the Terrans put an end to the ultra-long-baseline gravity-wave observation project. But Atwood’s data and
his hypothesis seem solid to me.”
Agnes peered at the girl with narrowed eyes. She had practically raised both Aguri and Atwood. They were the first members of Agnes’s Mafia, which had led some parents to joke that giving one’s child a name beginning with
A
was essential for a future as
a first-rate scientist.
“I’ll concede that the data points in the direction you say. But don’t you think it’s premature to pin extraterrestrial intelligence on coherent gravity waves? After all, why use gravity waves? They penetrate interstellar dust and gas better than radio waves, but on the whole they’re too weak. Radio waves are technically far better
for communication.
“So we seem to have detected gravity wave transmissions. What about two centuries of monitoring for intelligent signals in the electromagnetic spectrum? We’ve found nothing. And even if we assume this is an intelligent signal, how do you account for the complete absence of similar electromagnetic signals? Of course, we’re not in a position to guess how an alien civilization would
choose to communicate, but still…”
“Maybe it’s more natural for them to use gravity waves. Maybe
their biology makes it easier. You can’t rule that out.”
“What kind of life-form would find it natural to use gravity
waves?”
“Well, for example, a life-form like the one you speculated about,
once upon a time.”
“How in the world did you find out about that?”
“Your paper on the nanomachine experiment is in the public
domain.”
“But there must be as many AADD experimental papers as there
are stars in the galaxy,” Dr. Agnes said.
“Yes, but the revolutionary ones are as scarce as the number of moons in our system. I didn’t find the math that hard to follow.
Well, okay, I had to pay careful attention to some sections.”
The relationship between the two women was more like that of an older sister and a younger sister than research advisor and student—sisters bound by shared outlook and vision instead of blood. They still lived in the same complex in Port Shiva, though Agnes traveled so often now that Aguri only saw her rarely. AADD’s family units
often followed this pattern; Agnes’s Mafia was no different.
Still, Agnes wouldn’t have expected Aguri to read all of her old papers. It certainly wasn’t essential for her work. But she understood why Aguri had made the effort—she wanted to know as much about Agnes as she could. Perhaps Aguri idolized her. Agnes had
nursed similar feelings toward some of her teachers.
“To be honest, something else made me remember that report just now,” said Aguri. “If the galaxy is filled with gravity wave transmissions, there must be evidence in Sol System. Gravity wave observation doesn’t have the history that radio astronomy does, but
we do have lots of data.”
“But Atwood is the only one reporting signals that seem to be coming from an extraterrestrial civilization. Application of the gravity-wave Doppler shift to observational technique is still in its
infancy. You may have trouble getting repeatable results.”
“Agnes, there’s corroboration. I found it in an old paper from
2123, right after they started work on the AAD.”
“2123…” Agnes caught her breath. The year was engraved in
her memory. Everything started in 2123.
“It was before Chandrasekhar Station was complete, when all they had was the ring around Kali—Ouroboros. You know the story. The ring’s AI was convinced it had detected gravity waves.
The result was nearly a catastrophe,” Aguri said.
Catherine Sinclaire had been Agnes’s instructor, and she had been on Ouroboros when it happened. Catherine had been young at the time—almost a child, really. Agnes knew her report of the incident by heart. Catherine and her partner Tatsuya had told her the story many times; reliving it together had become a kind of
family tradition.
“Yes, I know about that incident,” said Agnes.
“Do you know what I thought when I read your paper on the experiment?” Agnes didn’t answer, but she could guess what Aguri was about to say. “Aiming a gravity wave transmission at a black hole implies a receiving entity. That’s why you fired nanomachines
toward Kali, isn’t it? To find that entity?”
Agnes’s hunch had been correct. “I was your age when I did that experiment. Maybe your examination of the existing data is
the next logical step.”
“But why didn’t you confirm it with another experiment? Maybe
they wouldn’t let you then, but you could do it now.”
The question awakened painful memories for Agnes. “I have to think about others now,” she said at length. “About what’s best
for AADD.”
Aguri clearly didn’t understand. Agnes felt she was looking into a mirror. At Aguri’s age, she hadn’t been able to grasp the concept
of personal responsibility either.
“That incident has always been attributed to AI failure,” said Aguri. “But the gravity wave transmission the AI detected was
identical to Atwood’s signal. At least, the format is the same.”
“There’s another interpretation. Maybe Atwood’s signals and the Ouroboros signal both come from regular, human-induced
structural perturbations.”
“But
Shantak II
’s detectors are suspended in a magnetic field, isolated from the ship and from external vibrations. You know that as well as I do. We can rule out a false reading. The only other possibility, given the identical signal formats, is that the Ouroboros AI really was picking up a gravity wave transmission like the one
we’re seeing now.”
“Then why haven’t there been any transmissions aimed at the
AAD since then?” Dr. Agnes asked.
Aguri stared, baffled. Agnes was a scientist. Even now she must be convinced that Kali harbored an unknown life-form. Why look for objections to data that might point to the reality of an extraterrestrial
civilization?
“Agnes, listen to me. We changed Kali’s orbit. If the Ouroboros signal was originally intended for Kali, the black hole isn’t in the right location to receive it anymore, because we moved it. These
transmissions appear to be very tightly focused.”
“Appear to be, yes. But that’s just an assumption. Focus presupposes intention, and there may be no intention at all behind these signals. It’s all speculation. We have very little reliable data. How
are you going to get around that?”
“There is a way—manned interstellar missions. If the signals beamed at our system are being transmitted to other stars in the galaxy, we should be able to verify that. And that calls for sending
humans, not just probes!”
“Manned spacecraft have to be far more reliable than probes,
you know.”
“I think it would be worth it,” Aguri said.
“Is that why you came to see me personally?”
“Is that a problem?”
“Talking to me personally isn’t going to move things forward. If you really think manned interstellar missions are necessary, submit a formal proposal. If you convince the steering committee, then in ten years your first spacecraft might be departing on its mission.”
“
My
spacecraft?”
“Of course. Once you propose it, it’s your baby.” Agnes felt a twinge of déjà vu. Eighteen years ago, when Agnes had described her idea for an experiment to fire nanomachines through Kali’s
ergosphere, Catherine had said the same thing to her.
Eighteen years from now, Aguri would say these words to someone else. Who would it be?
2171
Port Shiva, Titania
Agnes hurried over to the console where Shi’en was standing. “What do you mean she’s in no condition to leave port? What’s
going on?”