Further: Beyond the Threshold (27 page)

“Well, troops,” I said, setting down my cup of buna, while the others settled into chairs at the surrounding tables, “where are we going next?”

With the shakedown cruise successfully completed, the
Further
was ready for its first new mission.

“Isn’t that really up to you, Captain Stone?” Xerxes said. “After all, as majority shareholder in the
Further
, the Plenum is in a position to select whatever destination it likes, with the wishes of the other shareholders following in subsequent missions.”

“True,” I said. “And since I’m the sole Voice of the Plenum on the ship, the decision is mine, and I’m deciding to open the floor for suggestions. So”—I glanced around the room—“any suggestions?”

The responses were hardly surprising, given our previous discussions. Zel and the brothers Grimnismal wanted to search for their exotic matter and had laid out a list of likely places to begin looking. Maruti, for his part, wanted to search for proof of the Demiurgist doctrine and suggested that we journey to a particular planetary nebula, some distance from Entelechy space, that early reconnaissance probes suggested had some interesting characteristics. Even our waitron Ailuros had a contribution; though, given her brief history with Maruti, I understood her suggestion that we seek out a possible home for feckless chimpanzee philanderers to be an unsubtle jab in his direction, to which Maruti only shrugged, a halfhearted expression of apology on his face.

With Ailuros’s suggestion as a possible exception, all the recommendations were precisely what I would have anticipated. But when all the other principal shareholders had voiced their suggestions, Xerxes had so far remained silent, sitting near the open window, eir attention on birds in flight.

“Xerxes,” I said, calling out, “what was that pulsar you told me about the night we met?”

Ey turned eir eyeless face to me, a gesture entirely for my benefit. “The binary pulsar we discussed on Cronos, do you mean?”

I nodded.

Ey sighed. “The pulsar is part of a binary system, four hundred and sixty light-years from Sol, a little under fifty light-years from our present position. It was known by scientists in your era, Captain, as PSR J0437-4715. With a period of only five-point-seven-five milliseconds, it is the nearest and brightest millisecond pulsar to Sol. The rotating neutron star is about one-point-three-five solar masses, and its white dwarf companion is point-one-three solar masses, and the system has an orbital period of five and a half days. Five billion years old, the neutron star consists of two components, a nonthermal power-law spectrum generated in the pulsar magnetosphere, with a photon index of about two and a thermal spectrum emitted by heated polar caps, with a temperature decreasing outward from two MK to half an MK. The neutron star surface is covered by a helium atmosphere. Unlike other pulsars, it lacks a synchrotron pulsar wind.”

The other command crew began shifting, restless.

“Um, yes, OK, thanks, Xerxes,” I said. “Now, could you tell us
why
this particular pulsar interests you?”

“Ah.” Xerxes nodded. “Yes. Well, the details of this binary pulsar have been well established since the Information Age, but in recent years, the periodicity of the pulsar has changed slightly—no more than a few hundred thousandths of a percent—but the orbital period and radial velocity of the binary has slightly increased, suggesting that the mass of the system has changed.”

“That’s impossible,” Zel said dismissively.

Xerxes shrugged. “I’ll allow that it is definitely improbable, First. But impossible? Through natural mechanisms, certainly. Neither the Exode nor the Entelechy know of any means through which such a system could lose mass so quickly, which suggests an intelligent agency.”

“And how long would it take to get there?” I asked.

“From our present location? Travel time would be five days, the maximum distance the
Further
can travel before needing to stop and allow the metric engineering drives to recharge. But we wouldn’t be able to leave for the better part of a day while the drives recharge.”

I clapped my hands and rubbed them together. “I think we have a winner, folks,” I said, smiling. “We’re going there.”

I climbed to my feet as the others raised their voices in protest, all but Xerxes, who turned serenely back toward the window.

“Ailuros,” I said, waving to our waitron. “I’ve been thinking about taking a tour of the drive engineering decks, and this seems as good a time as any. I hate to drag you away from waiting tables, but if you’re not terribly busy, would you mind giving me a brief tour?”

The cat shrugged out of her apron. “Why not?”

I followed her toward the door, the complaints of the others drifting after me. “Don’t worry,” I said, glancing over my shoulder. “We’ll get to all of your ideas, sooner or later. But I left Earth to explore, and I’m damned if I’m not going to do a little
exploring
!”

I still wasn’t sure why the Plenum had picked me as their representative on the crew, but I wasn’t about to look a gift horse in the mouth. Since I’d stepped through the threshold onto Alpha Centauri, completing in a few strides the journey I’d dedicated my life in the 22C to accomplishing, I’d been unsure what I would do next, what frontiers there might remain for an explorer like me to visit.

Now we would see.

Leaving the café, Ailuros and I boarded a tram, which whisked us off toward drive engineering.

“I’m somewhat surprised you haven’t toured the drive engineering section previously, sir.”

“I wanted to do so,” I answered, “but I think that I wore out my welcome a bit with the brothers Grimnismal the other day, when they were giving me a tutorial on wormhole engineering. I didn’t get the impression that they’d be eager to chauffer me around their deck on a sightseeing tour.”

“Well,” the cat said with a slow blink and a nod, “the corvid brothers are known for getting on the nerves of others, so it probably served them right. Believe me, I work in drive engineering because I love my generator, not because I hold any especial affection for the Grimnismals. At least waiting tables in the café I’m likely to be acknowledged for my efforts on occasion, perhaps even thanked. The brothers view everyone as a potential audience for one of their self-aggrandizing lectures about their personal brilliance and how the exotic material whose existence they’ve predicted is going to revolutionize the Entelechy.”

“Do you really think that stuff exists?”

“A completely unknown type of material that will allow us to maneuver thresholds anywhere in the galaxy at faster-than-light velocities?” She smiled, eyes half-lidded, an expression I recognized from any number of housecats I’d had as a kid. “Well, it would be nice, wouldn’t it? But I wouldn’t hold your breath waiting for it, sir.”

In a matter of moments, we’d reached drive engineering, the central deck of the ship. It appeared to be one immense space, some two kilometers across, the ceiling overhead twenty meters above the ceiling below. The tram stopped near a network of gantries halfway in between, with a sphere a short distance meters away connected to the walls in all directions by a network of thick pipes or cables.

“Careful climbing out of the tram, sir,” Ailuros said, vaulting out ahead of me. “Step too far and you’ll end up bobbing up and down at the change point, and that can be pretty unsettling to the digestion, I assure you.”

At first, I had no idea what she was saying. Then I stepped out onto the gantry and looked down to see a pair of crewmen walking upside down on the
other side
. It was then that I understood that I was standing precisely at the central plane of the
Further
, the level to which gravity in both hemispheres pointed and that the “floor” ten meters below me was another ceiling in the opposite direction.

It was a strange sort of vertigo, standing at the edge of the walkway and looking down, with nothing but empty space before me, but I understood what Ailuros had meant.
Down
as a concept ended somewhere just a few centimeters beneath my feet, so if I fell over the side, I’d be falling
up
for a moment, then down again past the center point, then up, then back down, yo-yoing back and forth across the center plane of gravity until I burned off enough momentum of air friction that I just hung motionless in the middle, my head and feet both attracted “down” to my waist. I could see that it would be a bit upsetting to the stomach, to say the least, and was glad I hadn’t had a large breakfast that morning.

Ailuros had already set out across the gantry, heading to the sphere in the near distance. I hurried after her, careful to keep well away from the edges of the walkway.

I caught up with the cat as she stopped a few meters from the sphere. Standing so close to it, I realized it was much bigger than I’d earlier guessed, at least nine meters in diameter, and that it had only seemed small when seen against the vast stretch of the two-kilometer-wide space.

“That’s the power generator,” Ailuros said proudly, and I could hear the faint rumble of a contented purr beneath her words.

“It’s pretty big,” I said, with a low whistle.

The cat nodded. “Couldn’t be any larger and still be able to maintain the necessary negative energy state in the interior, couldn’t be any smaller and still be able to contain a sufficient region of quantum vacuum. It sits at the exact center of the ship’s central sphere, which is some two kilometers across.” She pointed to the network of pipes and cables radiating out from the sphere toward the walls, a kilometer away in every direction, making the generator look like a spider sitting at the center of its web. “Those run to the drive elements in the ring, which extend another kilometer beyond the hull.” She looked over at me, smiling. “Did you know that if the generator were a scale model of Sol, then the ring begins roughly where Earth’s orbit would be located?”

I allowed that I didn’t, as a matter of fact.

“As I’m sure you’re aware, unlike convention craft or planet-side structures, the
Further
’s power generator draws its energy directly from the quantum vacuum itself.”

“Right,” I said, nodding. To prove I wasn’t a completely ignorant primitive, I added, “In my day, it was sometimes called zero-point energy, since it’s the energetic ground state of empty space.”

The cat nodded appreciatively. “A fairly apt name, I suppose. I’m a bit surprised to discover that the quantum vacuum was known about, even in ancient times.”

I smiled slightly. “Well, it wasn’t all stone axes and mastodon hunts, I assure you.”

“Oh, no disrespect intended, sir,” Ailuros said hastily. “It’s just that I’ve been studying the quantum vacuum for three lifetimes now, and only now do I feel like I’ve even begun to grasp the essentials. I was formerly a philosopher of sorts, I suppose you could say, but my research led me to an analysis of physics, which led me to the study of the quantum vacuum, which led me ultimately to the
Further
. The corvid brothers may be more interested in the metric engineering capacity of their drives”—she gestured toward the outer hull and the equator of dark machinery that circled all around—“if not the sound of their own voices, but my passion is reserved only for the power generator itself.”

A wide platform circled the sphere, which lay half in one hemisphere and half in the other. I circled slowly around the sphere, which seemed an unremarkable ball of dark, gray metal. “Something confuses me, Ailuros. If the quantum vacuum represents an essentially inexhaustible supply, why aren’t similar generators more widely used? And especially given that the Entelechy uses power as a means of exchange. Why don’t planets or habitats build similar engines to supply power for themselves?”

“I’ve been arguing that for years,” she said, somewhat sadly, “but I’m afraid the economics simply don’t bear out. The energy required to construct the generator in the first place far outweighs its capacity to generate more. It simply isn’t a cost-effective solution as a means of power generation for a world to adopt as a source of power.”

“Ah. There were similar issues in my day, I suppose. Gold was a valued commodity, because of its rarity, but anyone could generate more gold if they wanted to do so by transmuting platinum into gold by bombarding it with neutrons, but the cost of the production was more than the result was worth.”

“Mmm. Alchemy.” She nodded knowingly. “I knew that was practiced by the ancients. Well, the whole system costs an arm and a tail just to keep running. Every time the drives create a bubble of distorted space, it costs roughly the entire energetic output of a developed world over the course of a standard day, and that’s after pouring the equivalent of a planet’s energetic output for one hundred years into building them in the first place. That’s why you’re not likely to see many habitats and ships using metric engineering to induce artificial gravity on board, when you can just use centrifugal spin at an infinitesimally small fraction of the cost.”

Out of the corner of my eye, I saw another tram lower down through the ceiling and come to rest on the gantry. A pair of unlikely looking creatures stepped out and started for us. It was the Ganesh, Vinayaka, and the blue-skinned, four-armed Sarasvati, the Vedas who’d visited me on Earth and who’d hosted my brief visit to their habitat, Thousand-petaled Lotus. I’d glimpsed them the night before in the reception but had just assumed that they were visiting dignitaries. All the dignitaries had left the ship overnight, though, so the fact that they were still on board meant that they were actually part of the crew.