Xeelee: Endurance

by Stephen Baxter

  ‘True.’ Kaser eyed Rhoda. ‘The technology’s in place. The only question remains, do we use it?’

  Rhoda thought it through.

  The Squeem occupation had changed human perceptions of the Galaxy, and humanity’s place in it. A historic loss of innocence.

  Now humans were tentatively moving out beyond the Solar System once more. And everywhere they went, they found life. Intelligences swarming and squabbling. A kind of Galactic society, a ramshackle pecking order based on avarice, theft and the subjugation of junior races.

  And for humanity, a future that contained nothing but threat.

  The black holes in Jupiter were clues to a closely guarded secret, which Rhoda hadn’t even shared with Reg Kaser. The Squeem invasion hadn’t been the first hostile alien incursion into the Solar System. Some centuries back invaders, who would occupy Earth in their turn some time in the future, had come back in time to secure their victory over mankind. They had crossed a kind of time bridge built by the legendary, or notorious, engineer Michael Poole, and created a crisis the historians called ‘The Emergency’. And in the course of the final battle to exclude them, miniature black holes had been hurled into Jupiter. During the Squeem occupation, knowledge of this event had mostly been lost, and was only now being pieced back together by the historians. But the mortal wound inflicted on Jupiter was unarguable. Some analysts, poring over the historical reconstructions, argued that the source of the Emergency invasion might lie only decades away, in the future.

  And even beyond that hazard lay: not least the Xeelee, secretive, xenophobic, indifferent. And so advanced they made the rest of the Galaxy’s inhabitants look like tree-dwellers.

  The future held hierarchies of enemies. And that was the basis on which Rhoda had to make her decision.

  Rhoda stared down at the ice landscape of Rhea, imagining the stranded Squeem swarming within. ‘It won’t be revenge,’ she said. ‘Call it insurance. Look at what the Squeem did to us. This will be one danger eliminated.’

  ‘We’re setting a precedent for the future.’

  ‘The future leaves us no choice. And if this makes us tougher as a species, good. When the weapon’s ready, make sure Hume is online when the signals reach Earth, would you? He ought to watch this, as the Squeem made Harry Gage watch. Let this be remembered.’

  Kaser stood. ‘I’ll call the weapons crew.’

  In retrospect, the yoke of the Squeem had been thrown off with comparative ease. Humans moved out into the Galaxy again, in new ships based on the Squeem hyperdrive . . . a technology stolen, at second-hand, from the Xeelee.

  Then humans encountered their next conquerors, just as had been predicted in the fragmented histories of the Emergency. Those shards of foreknowledge proved of little use. The new overlords were called the Qax. Once more the worlds of mankind were taken. Once more people were made to grow old.

  And, even at such a distance in time, the hubristic feats of Michael Poole continued to affect human lives.

  ENDURANCE

  AD 5274

  1

  Chael smiled at Mara. Beside Chael stood the sullen Engineer he had introduced only as Tasqer. And with them, in Mara’s living room, stood the Virtual avatar of Jasoft Parz, probably the most powerful human being in the Qax dominion of mankind.

  Mara had never trusted Chael, her husband’s brother, even before Pell had died, and she didn’t trust him now. But here he was with these extraordinary characters, telling her about the most outlandish project she’d ever heard of.

  A project to which, it seemed, her own son Juq was somehow the key.

  ‘We even have a name for the ship we’re going to build,’ Chael said.

  ‘The ship you’re going to build for the Qax,’ Mara pointed out.

  ‘For the Qax, yes. Everything we do is for the Qax. But this is a chance for humans to achieve something for themselves, under the yoke of the Occupation – even with the encouragement of the Qax Governor—’

  ‘The ship you want my son and his toys to contribute to, somehow.’

  The unreal spectre of Jasoft Parz, Ambassador to the Qax, smiled with an odd serenity. ‘Time is short, Mara. The Governor wants this craft, a Poole-technology GUTship towing a navigable wormhole mouth, built and launched within six months. GUTship engineers we have . . .’

  And he nodded to the taciturn Tasqer, the Engineer. In dark, practical-looking clothes, Tasqer was perhaps forty, and though heavy-set he had the pallid look of the space-born. Since this little party had come floating down to Mellborn in a flitter from the sky, Tasqer had said not a word, and he said nothing now, meeting Mara’s gaze coolly.

  ‘But,’ Parz went on, ‘wormhole builders are another matter. And so when my old friend Chael here came to me and pointed out your son’s experiments . . .’

  Mara found it difficult even to listen to this nonsense. Jasoft Parz himself was a distracting presence. Parz looked around seventy years old, with a round face, white hair, finely robed. But he moved with the ease of a younger man, Mara thought suspiciously. She looked at him more closely.

  And were there black roots showing under that mop of white?

  She tried to suppress her reaction, the shock of recognition. But Parz smiled at her. He wasn’t hard to read – or rather, he was more than skilful at projecting his true meaning. Yes, he was saying, she saw suddenly, that through this strange scheme the ultimate prize was indeed available: AntiSenescence treatment. Life itself. All she had to do was play along.

  Suddenly Mara’s attention was fully focused.

  Chael said now, ‘Juq’s experiments, yes. Young people building spacetime wormholes in their bedrooms and back yards! It’s a remarkable story – it turns out there’s a kind of global craze for such things, loose societies of enthusiasts communicating and sharing. It’s just like the rocket clubs that formed before the first age of space.’

  Parz said, ‘Well, not all the ingenuity mankind showed in the heroic days of Michael Poole has been lost, evidently. Here is something we can build on. And your son, Mara, is in the vanguard of developments.’

  Actually, Mara thought, not so much her son, not handsome, plausible Juq, but his smarter but lower-class buddy Tiel. She wasn’t so blinded by her love for her son that she couldn’t see where the brains in that partnership lay.

  Chael said, ‘We see Juq as a potential leader of this aspect of the project, young as he is.’

  She eyed her brother-in-law, and Parz. That made sense, at least. ‘Hm. A bright, good-looking son of an old military family? Yes, he’d be a good front for this operation, wouldn’t he? You’ve an eye for figureheads if nothing else, Ambassador.’

  Chael said seriously, ‘It’s not a trivial point. Image matters. Both my family and yours, Mara, do have respectable pedigrees dating back to Navy service in the days of the rebellion against the Squeem.’

  Parz said carefully, ‘And now you serve in a different way, as I strive to do, in making life bearable for billions under the administration of the Qax.’

  Of course that was true, in its way. When the Qax had almost effortlessly taken over the Solar System, rich old families like Mara’s, seamlessly embedded in hierarchies of wealth, privilege and power, had seemed to find it easy to transfer their loyalties to the new alien rulers. Their justification was that without their selfless negotiating with the Qax, the lot of the rest of mankind could be considerably worse.

  But especially since Juq had started bringing his friend Tiel home to play with their wormhole experiments – and Tiel had let leak a few details of the lives he and his family led, brief lives spent labouring on the coastal algae farms, or on the great sea-bound transport canals and sewage ducts, until ending in old age or terminated by diseases that had once been banished from Earth – Mara had become uncomfortably aware, here in her grand home in the heart of ancient Mellborn, what privileges she and her family en
joyed, and how morally compromised she had become . . .

  Yet she looked again at those odd black roots under Parz’s white hair. The most cruel imposition of the Qax regime, like the Squeem before them, had been the removal of AntiSenescence treatments, which for millennia had enabled humans to postpone death. Though there were endless rumours of illicit sources of AS, and of secret groups of undying living among mortal humans, not even the most senior in the Qax’s human administration had legal access to such treatments. In theory. Now it seemed that wasn’t true. What was she being drawn into here? And – could she refuse the implicit offer, for herself and her family?

  Jasoft Parz caught her looking at him, and smiled again.

  ‘Well,’ she said briskly. ‘Before we go any further with this conversation you’d better come meet the boys and see if what they’re building is actually any use to you. The staircase down to the cellar is this way . . .’

  The townhouse was very ancient, and the cellar more so, perhaps millennia old, Mara suspected. But she’d had it renovated recently. Hovering light globes made the roomy chamber bright as day, illuminating walls now overlaid with the boys’ images of the heroic days of wormhole-building when Michael Poole and his colleagues had laced the Solar System with their faster-than-light transit tunnels.

  Both Juq and Tiel waited for them here, dressed in clean coveralls, standing beside the long table on which they’d set up their latest experiment. The neatness had been Mara’s mandate; she wanted them to look like smart young engineers, not teenage hobbyists. They would always be an ill-matched pair, however. Though at seventeen Tiel was a year older than Juq, he was a good head shorter than Mara’s son, no doubt some consequence of diet and upbringing.

  The Virtual Jasoft Parz greeted Juq with a smile. ‘It’s good to meet you, my boy. I did know your father – a good man.’ He spread his hands. ‘And I’m sorry I can’t be here in person.’

  ‘I’m pleased to meet you too, sir.’

  Juq, tall, blond, blue-eyed, handsome, had never been short of confidence, Mara knew, even if he had never been academic. And he was instantly likeable, as she could see despite her mother’s bias. She’d never had any doubt that with such attributes, coming from such a family, he’d find a place in the world. But she’d never expected him to be caught up in spacecraft experiments – or at least she’d imagined it would be nothing but a boyhood fad . . .

  Parz glanced around. ‘I’m surprised to find you working in a cellar. Why not above ground, in the daylight?’

  Tiel and Juq glanced at each other uneasily.

  Chael stepped forward. ‘Call it caution, Ambassador. I know from my own fond memories that my nephew here has been fascinated by the Poole era since he was small. Books, dramas, even the imagery you see here on these walls. We saw no harm in it – we should be proud of the human past – even if the Squeem did shut down the old Poole tunnels long before any of us were born. Then when he found it was possible, in principle, to build a wormhole in a home workshop—’

  Juq took over. ‘Sir, I know experiments with spacecraft technologies are indicted under the Occupation.’ He glanced over at Tasqer the Engineer, who gazed back. ‘I wasn’t sure if this qualified. After all, a wormhole isn’t spaceflight technology in itself; in fact, to use a wormhole to travel through space, you would have to use a spacecraft to tug the Interfaces into position. But I didn’t want to get my family into trouble.’

  Parz nodded. ‘And so you hid it all away down here.’

  Juq squared his shoulders. ‘I am prepared to take full responsibility for any breach of regulations, Ambassador.’

  Chael beamed. ‘You see, Jasoft? You remember what I told you about this boy? Smart, intelligent, and morally upright. What a credit to the family, to the race!’

  Parz gave Mara the slightest of smiles, showing he wasn’t entirely taken in by this salesmanship. But Mara couldn’t blame Chael, she supposed, for working so hard to obtain for the family any benefits that might accrue from this peculiar opportunity.

  Parz said now, ‘Perhaps you’d better show me this marvellous experiment of yours.’

  Juq led him to the table, where Tiel stood waiting. Juq said, ‘Maybe you’d be best at talking the Ambassador through it, buddy.’

  Suddenly Tiel looked terrified. Mara imagined the only figures of authority who had spoken to him before had been work supervisors and police. He opened and closed his mouth, and said, ‘Sir – Ambassador—’

  ‘Take your time,’ said Parz kindly. He stepped up to the table, which was low and long and topped by an airtight transparent cover, and cluttered with heaps of equipment. Parz passed a Virtual hand through the cover, making blocky pixels sparkle. ‘I understand this is a mere model.’

  ‘But it is a fully functioning wormhole,’ said Tiel, more confidently now. ‘A flaw in spacetime that enables faster-than-light travel from one end of the table to the other. You can’t see the Interfaces, of course, they’re microscopic. And all we can pass through is laser light. But—’

  ‘But the wormhole is stable, yes? I understand that’s the trick, the hard part. Wormholes tend to collapse on themselves—’

  Tiel said too quickly, ‘In fact they get locked into causal feedback loops and detonate.’

  ‘You need a kind of antigravity to keep the wormhole throat open – is that correct?’

  ‘Yes, sir,’ Juq said. ‘More precisely you need what’s called “exotic matter”, a peculiar kind of matter with a negative energy density. Yes, it works like antigravity.’

  By now even Mara had been forced to learn how wormholes worked – in particular that a wormhole without exotic matter in its throat was useless. Lethal tidal forces would bar the wormhole portals, the portals themselves would expand or collapse at light-speed, and the smallest perturbations caused by any infalling matter would result in instability and collapse. So, in their designs centuries ago, Poole’s team had learned to thread each of their wormholes with ‘exotic matter’, to provide an antigravity effect in the throat to keep it open. The wormhole was still intrinsically unstable, but with feedback loops it could be made self-regulating – but the negative energy levels Poole had needed were high, equivalent to the pressure at the heart of a neutron star. It had been a challenge for Poole, and was a challenge now.

  Parz said, ‘I do know that fifteen centuries ago Michael Poole harvested his exotic matter from the orbit of Jupiter. Whereas here—’

  ‘We’ve had to be more subtle,’ Juq said.

  Tiel said, ‘Actually, I had the idea when I was working on a landfill processing detail.’ Combing through millennia-old garbage, Mara knew, for reusable materials, chemicals, even artefacts; all over the planet the occupying authorities had people sifting the debris of their own past for materials the Qax could sell off-world. ‘And I found these.’ Tiel held up threads of very fine fibre on the palm of his hand. ‘There are splinters of diamond attached to these optic fibres, sir. Very small, very fine. I have no idea what kind of machine these came from, once. But I realised that with these I could make—’

  Juq put in, ‘He got the proper permissions before removing the materials from the site, Ambassador. The threads were of no discernible value and had no weaponising potential.’

  Parz waved a hand. ‘Yes, yes. Just tell me what you did, boy.’

  ‘It’s technical, sir. At the quantum level all matter and energy, a beam of photons say, is naturally a mixture of positive and negative energy. Although the net balance is always positive, overall.’

  ‘All right. This positive energy is the ordinary stuff we use to heat our homes and power our flitters?’

  ‘Yes, sir. And negative energy is – well, it’s a gap where energy ought to be. And it’s equivalent to exotic matter. In a way – the mathematics is subtle . . . What you have to do is squeeze the vacuum – that’s the phrase we use – so that the negative component of the energy
is separated out, and can be gathered. Here we do that by using the diamond splinters to manipulate photons in a light beam one by one. And we capture the negative energy in a mirrored cavity, which—’

  Mara thought Jasoft’s eyes were glazing over. ‘Maybe you’d better just show the Ambassador how it works, Tiel.’

  In fact, much of the experiment had to be taken on faith, since the wormhole mouths were too small to see. The boys had set up two fine laser beams, passing through a narrow vacuum chamber set up on the table: beams which cast spots of ruby light on a plate at the table’s far end. One beam was passed unimpeded, the boys said; the other was sent through a wormhole a metre long. And the photons in the second beam, travelling instantaneously between the wormholes’ tiny Interfaces, took a few nanoseconds less to travel the length of the table: a small interval, but sufficient for the boys to demonstrate with a precise clock.

  ‘I’m impressed,’ Jasoft Parz said. ‘Junk from a landfill, a home workshop – and you’ve built a stable wormhole. Very impressed.’

  Chael beamed. ‘Told you so, Ambassador.’

  Mara stepped forward. ‘Well, I’m still in the dark. Even if it’s possible somehow to scale all this up from a tabletop . . . The Qax want us to replicate Poole’s work, correct? To build a navigable wormhole, and then to drag one end across space in a slower-than-light GUTship. Why do they want to do this? And why a GUTship? It was great technology fifteen hundred years ago, but those ships are slower than light. The Qax have those Spline starships of theirs, capable of faster-than-light travel. So why would they want this?’

  ‘It certainly harks back to our past,’ Chael said quickly, evading the question, and evidently anxious to reassure the Ambassador. ‘Which is why it’s so valuable for morale. Hence my suggestion for the ship’s name, Endurance, used many times since but originally referring to a great exploration craft of the late second millennium—’

  ‘I can tell you what’s prompted the Qax to do this,’ said Engineer Tasqer, surprising them by speaking at all, Mara suspected. He stepped forward and searched the boys’ images on the wall. Most of them showed Poole and his colleagues, legendary names in their own right like Miriam Berg and Bill Dzik – faces with the eerie agelessness that came from decades of AS treatment, Mara thought, from a time when it was unimaginable that such a thing could ever be lost.