away from some source of pain.
Jasoft closed his eyes and, with a subvocalized command, ordered the software in his eyes to call up an external image of the Spline, transmitted from the companion ship.
His craft was entering the portal face, inching forward as delicately as any docking, the curves of its flanks almost brushing the powder-blue edges of the tetrahedral framework.
Parz was a hundred hours away from the past.
The Qax spoke abruptly, its decision evidently made. 'The human was — will be — called Jim Bolder. A man of the Occupation era — from not far into your own future, Parz.
'Bolder was one of the last human pilots. Eventually the Qax interdiction on human operation of spacecraft will become complete, Jasoft Parz. Ships will be impounded on landing. The off-Earth human colonies will become self-sufficient. Or they will be closed, their inhabitants returned to Earth. Or they will die.
'Men such as Bolder will lose their vocation, Parz. Their reason to be. This made — will make — it possible to recruit Bolder for a special assignment.'
The clean geometries of the Interface framework looked stark, inhuman, against the flesh of the Spline. At one point the Spline came within a few dozen yards of brushing the frame itself. Flesh toughened against the rigors of hyperspatial travel was
'What was Bolder’s assignment?' Parz asked.
'Parz, what do you know of galactic drift?'
Galaxies — and clusters and superclusters of galaxies, across half a billion light-years — were moving in great, coherent streams through space. It was as if the galaxies were moths, drawn toward some unseen light… Human astronomers had described such drift for centuries, but had never been able satisfactorily to explain it.
'What does this have to do with Bolder?'
'We suspected the drift had some connection with the Xeelee,' the Qax said.
Parz snorted. 'Come on. The Xeelee are powerful, but they’re not gods.'
'We sent Bolder to find out,' the Qax said mildly.
Parz frowned. 'How? That’s impossible. Even in the fastest of our hyperdrive craft it would take centuries of subjective time—'
'We had access to a Xeelee ship.'
Parz felt his jaw working. 'But that’s impossible too.'
'Such details are unimportant. It is sufficient that Bolder survived his journey to the center of the streaming.'
'To the place where all the galaxies go.'
'Yes,' said the Qax. 'Although, close enough to the center, Bolder found that the structure of all but the most compact ellipticals was shattered; galaxy fragments, stars and worlds, tumbled into the immense gravity well at the center of it all, their blue-shifted light tumbling ahead of them.'
'And at the bottom of the well?'
The Qax paused.
To Parz, still studying the Spline from without, it was as if the portal framework were scorching the flesh of the hapless Spline. But it wasn’t heat, he knew, but sleeting high-frequency radiation and gravity tides raised by the superdense exotic matter that were damaging the Spline so.
Parz shuddered in sympathy with the suffering Spline.
The image winked out. Parz, reduced to sudden artificial blindness, realized with a shock that his ship must now be totally inside the wormhole. With a feeling of claustrophobia and panic he snapped out subvocal commands.
His vision cleared.
The eye chamber had been reduced to the darkness within which he had awoken; his faithful globe lamp, floating beside him, cast his own shadow on the fleshy interior of the eyelid.
So the Spline had shut its eyes. Well, he couldn’t entirely blame it.
The ship shuddered, buffeted; entoptic fluid sloshed within its spherical chamber. Parz half swam to the nearest wall and clung to a ropy nerve channel.
'Gravitational stress,' the Qax murmured in his ear. 'This wormhole is a throat in space and time, Parz: a region of stress, immensely high curvature. The throat is lined with exotic matter throughout its length; we are traversing a tube of vacuum that runs along the axis, away from the exotic matter. The minimum width of the throat is about a mile. Our velocity is three miles per second—'
'Not fast enough,' Parz gasped.
Vibration traveled through Parz’s grasping fingers, up through his arms, and to his very core; it felt as if the Spline were being beaten by some immense fist. 'Can the ship endure this?'
'So the simulations tell us,' the Qax said complacently. 'But the creature is scarcely comfortable.'
'Right.' Parz clung to his nerve rope, imagining centuries unraveling around the hurtling Spline. 'Tell me what Bolder found,' he said through chattering teeth. 'At the bottom of the gravity well.'
A Ring, the Qax said. A torus. Composed of some unknown, crystalline substance. A thousand light-years across. Rotating at a respectable fraction of the speed of light.
It was massive. It had caused a well in spacetime so deep that it was drawing in galaxies, including Earth’s Milky Way, from across hundreds of millions of light-years.
'I don’t believe it.' Parz said, shaking in sympathy with the Spline.
'It is an artifact,' the Qax said. 'A Xeelee construct. Bolder watched the Xeelee build it.'
Xeelee craft — cup-shaped freighters the size of moons, and fighters with night-dark discontinuity wings hundreds of miles wide — patrolled the huge construction site. With cherry-red starbreaker beams they smashed the infalling, blue-shifted galactic fragments; they plated layers over the growing Ring.
'We believe the Xeelee have already invested billions of years in this project,' the Qax said. 'But its growth is exponential. The more massive it becomes, the deeper the gravity well grows, and the faster matter falls toward the site, feeding the construction crews further.'
'But why? What’s the point of it?'
'We speculate that the Xeelee are trying to construct a Kerr metric region,' the Qax said.
'A what?'
The Kerr metric was a human description for a special solution of Einstein’s equations of general relativity. When spacetime was distorted by a sufficiently massive, rotating toroid, it could — open.
'Like a wormhole?' Parz asked.
'Yes. But the Kerr metric interface would not connect two points in the same spacetime, Parz. It is a throat between spacetimes.'
Parz struggled to understand that. 'You’re saying that the artifact is a doorway — a way out of our universe?'
'Crudely, yes. The Xeelee are trying to build an exit from this cosmos.'
'And to do it they’re prepared to wreck a region of space hundreds of millions of lightyears wide…'
Suddenly Parz was blind again. Hurriedly, panicking, he snapped subvocal commands; but this time his vision would not clear. The darkness in which he was immersed was deeper than the inside of his own eyelids… it was, he realized with a terrifying clarity, the darkness of nothingness, of emptiness. 'Qax.' His own voice was muffled; it was as if all his senses were failing together. 'What’s happening to me?'
The Qax’s voice came to him, distant but clear. 'This is causality stress, Parz. The severance of the causal lines, of the quantum wave functions in which you are embedded. Causality stress is causing sensory dysfunction—'
Jasoft felt his body sense softening, drifting away from him; he felt as if he were becoming disembodied, a mote of consciousness without anchor in the external universe.
The Qax continued to speak. Its words were like distant trumpet notes. 'Jasoft Parz. This is as difficult for me, for any sentient being, as it is for you… even for the Spline. But
'Jim Bolder, in his stolen craft, evaded the Xeelee engineers. He returned to the Qax home system, where his journey had begun. Jasoft, the Qax are a trading nation. Bolder had returned with a treasure valuable beyond price: data on the greatest Xeelee artifact. It will not surprise you that the Qax decided to, ah, retain the data.
'But Bolder tricked us.'
There was a glimmering around Parz now, a ghostly shimmer, a reflection of ripples, like moonlight on a sea.
'The details have never become clear. Bolder should have emerged from hyperspace into a region surrounded by Spline warships, all bearing gravity-wave starbreaker technology… He failed to do so. Bolder survived, escaped.
'Starbreakers were used. In the confusion and panic, they brushed the Qax sun. It was enough to cause the sun to become unstable — ultimately, to nova.
'The Qax were forced to flee. Dozens of individuals died in the exodus. Our power was lost, and the Occupation of Earth crumbled…'
Jasoft Parz, bewildered and disoriented as he was, could not help but exult at this.
A gray light, without form and structure, spread into existence around him… No, not around him, he realized; he was part of this light: it was as if this were the gray light that shone beneath reality, the light against which all phenomena are shadows. His panic subsided, to be replaced by a sense of calm power; he felt as if he were light-years wide and yet no wider than an atom, a million years old and yet fresher than a child’s first breath.
'Qax. What the hell is happening?'
'Causality stress, Parz. Perceptual dysfunction. Causality is not a simple phenomenon. When objects are once joined, they become part of a single quantum system… and they must remain joined forever thereafter, via superlight quantum effects. You should imagine you are walking across a beach, calling into existence a trail of footsteps as you go. The footsteps may fade with time as you pass on, but each of them remains bound to you by the threads of quantum functions.'
'And when I pass out of my own region of spacetime?'
'The threads are cut. Causal bonds are broken and must be re-formed…'
'Dear God, Qax. Is this pain worth it, just to travel through time?'
'To achieve one’s goals: yes,' the Qax said quietly.
'Finish the story,' Jasoft Parz said.
'Finish it?'
'Why are the Xeelee building a way out of the universe? What are they seeking?'
'I suspect if we knew the answer to that,' the Qax said, 'we would know much of the secret truth of our universe. But we do not. The story must remain unfinished, Jasoft Parz.
'But consider this. What if the Xeelee are not seeking something
'What do Xeelee fear, do you suppose?'
Parz, buffeted, disoriented, could find no reply.
