Xeelee have let you get as far as you have.”
“We have concealed well… Jack Raoul, are you still human?”
I would have shrugged. “I don’t know.”
“You don’t sound as if you care.”
“Why should you?”
“I have known you for a long time, Jack. Among my people there are analogies for the grief you felt at the loss of your wife.”
“Ambassador, do you think this is some complicated way of committing suicide? You invited me to take the damn trip, remember.”
“Human or not, you will still have friends.”
“You can’t imagine how much that comforts me.”
They disconnected my new senses during the hyperspace flight. “I apologize,” the Sink Ambassador said. “When we reach the quagma project site you will have freedom to inspect.”
“But you don’t trust me with the location.”
“I do not have a free rein, my friend.”
I spent the passage floating in a Virtual reality, trying not to think about what lay beyond my skin.
I emerged into a half-Universe.
I was in a Ghost intrasystem cruiser, a rough ovoid constructed of silvered rope. Instrument clusters were knotted to the walls. Perhaps a dozen Ghosts clung to the rope like berries on seaweed.
Above me I saw stars. Below me a floor of crimson mist, a featureless plane, extended to infinity.
A Ghost approached me.
“Ambassador?”
“We have arrived, Jack Raoul.”
“Arrived where?” I gestured at the blood-red floor. “What’s this?”
The Ambassador rolled, as if amused. “Jack, this is a red giant star. Are you familiar with astrophysics? This star is about as wide as Earth’s orbit. We have emerged a million miles above its boundary.”
I’m no small-town boy; I’d been off Earth before. But this was different. I felt the soft human thing inside my Ghost shell cringe.
I’d seen nothing yet.
The ship plunged into the interior of the star.
I cried out and grabbed at silvered rope. Glowing banks of mist shot upwards all around us. The Ghost crew floated about their tasks, unconcerned.
“Lethe, Ambassador.”
“I could not warn you.”
We emerged into a clear layer within the star. Far, far below was a dense ocean of fire, looking like some fantastic sodium-lit cityscape; beneath it something small, hot and yellow glowed brightly. We descended through slices of fire-cloud with startling speed.
The Ambassador said, “You are perhaps aware that this giant is a star in the latter part of its life. Its bulk is a gas whose density is only a thousandth that of Earth’s atmosphere, and whose temperature is well below that at the surface of Sol. Easily managed by your new skin. So you see, there is nothing to fear.”
Now the ship veered to the right, and we skirted a huge, blackened thunderhead. “A convection fount; complex products from the core,” explained the Ghost.
“The core?”
“Like a white dwarf star, about the size and mass of Sol. It is mostly helium by now, but hydrogen fusion is still proceeding in a surface layer.” The Ghost rolled complacently. “Jack, your visit — this project — is inspired by quantum mechanics. Do you understand the Pauli Exclusion Principle? — that no two quantum objects can share the same state? You may be amused to know that it is electron degeneracy pressure — a form of the Pauli Principle — which keeps that core from collapsing on itself.”
“You’re prepared to live inside a star, just to evade detection by the Xeelee?”
“We anticipate long-term benefits.”
We dropped into another clear stratus. The core was a ball about as hot and bright as the Sun from Earth; it rolled beneath us. Starstuff drifted above us like smog.
The Ghosts had built a city here.
Once this must have been a moon. It was a hollowed-out ball of rock, a thousand miles wide. Ghost ships swept over the pocked landscape.
At the poles two vast cylindrical structures gleamed. These were intrasystem drives, the Ambassador explained, there to maintain the moon’s orbit about the core.
Our ship approached the city-world’s surface — there was negligible gravity, so that it was like hovering before some vast, slotted wall — and, at length, slid into an aperture.
I turned to the Ambassador. “I won’t pretend I’m not impressed.”
“Naturally, after this demonstration, I will provide you with any backup data you require for your report.”
“Demonstration? Of what?”
A hint of pride shone through the thin, sexless tones of the translator chips. “We have timed your arrival to coincide with the initiation of a new phase of our project.”
“I’m honored.”
We hurtled along dimly-lit passages. Other craft dipped and soared all around us. Blocks of light tumbled from cross-corridors, reminding me irresistibly of pixels. I recalled Eve’s strange, ambiguous warning, and wondered bleakly if I really wanted to be present at the dawn of a “new phase.”
With a soundless rush we emerged into a spherical cavity miles wide. Beams of crimson starlight crossed the hollow, bathing its walls with a blood-red glow. At the heart of the chamber was a sphere. A couple of miles across, the sphere gleamed golden and was semi-transparent, like a half-silvered mirror. Platforms bearing Ghost workers hovered over its surface.
Some vast machine moved softly, within the confines of the mirrored sphere.
“Mr. Raoul, welcome to our experiment,” the Sink Ambassador said.
“What is that sphere?”
“Nothing material. The sphere is the boundary between our Universe… and another domain, which we have constructed by letting quagma droplets inflate under controlled conditions. Within this domain the ratio you know as Planck’s constant is reduced, to about ten percent of its value elsewhere. Other physical constants are identical.”
“Why the half-silvered effect?”
“The energy carried by a photon is proportional to the Planck number. When a photon enters the Planck domain the energy it may carry is reduced. Do you understand? It therefore sheds energy at the boundary, in the form of a second photon, emitted back into normal space.”
I asked if we were to enter the Planck space.
“I fear not,” the Ambassador said. “Our fundamental structure is based on Planck’s constant: the spacing of electrons around the nucleus of an atom, for example. If you were to enter the domain, you would be — adjusted. The device in there — an artificial mind — has been constructed to withstand such Planck changes. The device controls the regeneration of the domain from quagma; we are also using it to conduct computational experiments.”
The machine in its golden sac turned, brooding, like some vast animal.
“Ambassador, what is your purpose?”
The Ghosts, the Ambassador said, had two objectives. The first was to use the Planck boundary conditions to build a perfect reflective surface, an age-old goal of the energy-hoarding Ghosts.
The second objective was more interesting.
“The capacity of any computing machine is limited by the Uncertainty Principle,” the Ambassador said. “The exploration of, say, high-value prime numbers has always been constrained by the fact that energy changes within a device must remain above the uncertainty level.
“With the reduction in Planck’s constant we can go further. Much further. For example, we have already managed to find a disproof of an ancient human hypothesis known as Goldbach’s conjecture.”
Goldbach, it seems, speculated that any even number can be expressed as the sum of two primes. Twelve equals five plus seven; forty equals seventeen plus twenty-three. Centuries of endeavor had neither proved nor disproved the hypothesis.
The Planck machine had found a counterexample, a number in the region of ten raised to the power eighty.
“I guess I’m impressed,” I said.
The Ghost rolled gently. “My friend, age-old problems melt before our Planck machine; already several NP-type problems have—”
I told the Ambassador I believed it, and to dump down the details later.
The science platforms were pulling away now, leaving the gold-silver sphere exposed and alone.
The Sink Ambassador continued its lecture. “But we want to go further. We see this Planck-adjustment technique as a means of probing — not just the very large — but the infinite. Our device will verify some of the most important theorems of our, and your, mathematics, simply by a direct inspection of cases, all the way to infinity.”
I stared at the bobbing Ghost. “I think you’re losing me. Won’t an infinite number of cases still take an infinite amount of time? — and energy?”
“Not if the time and energy is allocated in decreasing amounts, so that the total converges to some finite value. And — if the Uncertainty Principle is removed completely — there is no limit to the smallness of energy allocations.”
“Right. So you’re going to take Planck’s constant all the way to zero.”
“That’s right. And, Jack, mathematical conjectures are just the start. A training exercise. The artificial mind is heuristic — it is flexible; it can learn. With its infinite capacity at our disposal we anticipate the dawn of a new era of—”
There was a spark, dazzling bright, at the heart of the silvered Planck sac. The mind-device thrashed like some grotesque fetus.
I knotted my fingers in a length of silvered rope. “Ambassador, ‘space could shatter.’ ”
“What?”
“What does that mean to you?”
“…Nothing. Jack, are you—”
The flame filled the sac, overwhelming the machine. For an instant the sac glowed brighter than the star core.
Then the sac turned silver. It looked like some huge Ghost. Images of the crowding science platforms, of the slotted walls of the city-world cavity, shivered over its flanks.
“Ambassador, what’s happening?”
