‘The Second Rememberer was in her thirties when the Squeem regime began to crumble – sooner than anybody had expected. She, too, died young. But she was able to pass on her knowledge to another in turn.
‘And so it went. Two centuries after the Squeem conquered Earth, I am the Sixth Rememberer.’
‘And you tried to recruit Lonnie Tekinene.’
Hume sighed. ‘That was the idea. I left it a bit late in life to be befriending ten-year-olds.’
‘But,’ the inquisitor said, ‘even though the Squeem fell so long ago, none of you thought to reveal the truth of all this oral history until now.’
Hume shrugged. ‘When would have been right? Each of the Rememberers has had to make that judgement. It was only when I learned of your pocket of Squeem, surviving in the Solar System after the passage of two centuries, that I judged the time was right. You need to know the whole truth about the Squeem in order to deal with them.’ His face twisted. ‘But I wasn’t sure. I’m still not.’
The off-screen inquisitor asked, comparatively gently, ‘So how do you feel now?’
‘Relieved. It’s a burden, to be the only one who knows.’
It took Rhoda Voynet and her crew another week of data-gathering before she felt ready to make her judgement.
She called Reg Kaser to her cabin, and fired up her percolator once more. Beyond her picture window, Saturn turned, its cloudy face impassive before the turmoil of living things.
‘They’ve started to find proof,’ she said to Kaser.
‘Of what?’
‘The freezing. The geologists, putting together pieces of the puzzle – as if they were the first of their discipline millennia ago, deducing the existence of past Ice Ages from erratic boulders and gouged valleys. The biologists, trawling the seabeds for crushed whale bones. My historian colleagues, finding traces of deleted records. Global evidence of a decade-long glaciation event. It was always there, but unnoticed; it just needed a framing hypothesis to fit it all together.’
‘So Hume was telling the truth.’
‘It seems so.’
‘Meanwhile,’ Kaser said, ‘I’ve been talking to the xenologists, who have been in contact with those Squeem down there under the ice. The Squeem have been making their own case.’
‘About what?’
‘About why we should be lenient. The Squeem say they suffered some deep trauma of their own. After all they are aquatic, they’re functionally fish-like, and it must have taken a huge disjunction to lift them out of their ocean and into space.’ Kaser scrolled through notes on his slate. ‘Something about an invasion, by yet another world-conquering species. The Squeem managed to enslave the slavers, took over their star-spanning technology, and started an empire of their own. Something on those lines. It’s complicated.’
Rhoda said harshly, ‘And that justifies them occupying Earth?’
‘I suppose that’s the argument. But you’re the commanding officer.’
‘I am, aren’t I?’ She looked him straight in the eye. ‘I want to know my options. Tell me about the weapon. The one that will destroy Rhea.’
Knowledge in the UN Navy was rigidly partitioned. It was part of Kaser’s job to bear secrets of destruction, until they were needed. Rhoda only knew of their potential. He looked away. ‘If you’re sure. This is need-to-know only.’
‘I need to know.’
‘It’s not a human development,’ Kaser said. ‘Not even Squeem.’
Rhoda glanced beyond Saturn’s limb, at the stars. ‘Something hideous we’ve found. Out there.’
‘Yes.’
Even under the oppressive Squeem occupation, humans had learned much.
They learned, for example, that much of the Squeem’s high technology – such as their hyperdrive – was not indigenous. It was copied, sometimes at second- or third-hand, from the designs of an older, more powerful species.
‘It was during the occupation,’ Kaser said, ‘that the name “Xeelee” entered human discourse. The primal source of all this good stuff.’
Rhoda shuddered. ‘And is this new weapon you’re offering me a Xeelee artefact?’
‘It may be. Stuff gets swapped around. Purloined. Modified. We don’t know enough about the Xeelee to say . . .’
Ridding Rhea of the Squeem was a challenge. The ocean in which they swam lay under kilometres of ice, and was wrapped around a core of ice and rock. The ocean itself could be easily cleansed, but it would not be hard for Squeem groups to hide out in cracks and crevices in the irregular core, the thick, uneven crust. Rhoda needed something that would cleanse the little moon, thoroughly.
‘Tell me what this thing does.’
‘Maybe you know that the planet Jupiter is being destroyed. Eaten up from within by a swarm of black holes.’
‘Yes.’ In fact Rhoda knew a little more about it than that.
‘If we could make a black hole,’ Kaser said, ‘we could throw it at Rhea and demolish it the same way.’
She nodded, vaguely horrified, but trying to think clearly. ‘That would do the job, But we can’t make a black hole.’
‘No. But we have a technology almost as good.’ He pulled up graphics on his slate and showed her. ‘It’s a way to create a dark energy black hole.’
‘A what?’
‘It’s all to do with quantum physics,’ he said.
‘Oh, it would be . . .’
It was a kind of freezing, like water to ice, a phase transition. But this would happen at the quantum level. In a ‘quantum critical phase transition’, ordinary matter congealed into a kind of superconductor, and then into sluggish stuff in which even subatomic fluctuations died, and mass-energy was shed.
‘It’s as if time itself is freezing out,’ Kaser said. He mimed with his hands. ‘So you have a spherical shell. Just a volume in space. You arrange for matter falling on its surface to go through this quantum phase transition. And as your input matter passes into the interior its mass is dumped, converted to vacuum energy. Dark energy.’
‘Why doesn’t this shell implode?’
‘Because dark energy has a repulsive effect. Antigravity. Dark energy is already the dominant component of the universe’s mass-energy, and the antigravity force it produces will drive the expansion of the universe in the future. So I’m told by the physicists. Anyhow, the repulsion can balance the infall of matter.’
‘It can balance.’
Kaser grinned. ‘That’s the engineering challenge, I guess. If you get it right you get a stable object which externally looks just like a black hole. Inside there’s no singularity, just a mush of dark energy, but any structure is destroyed just the same. These things are found in nature, apparently.’
‘And they are easier to make than genuine black holes.’
‘So it seems. You do need a big box of exotic matter – that is negative-energy matter – to make it work.’ He kept grinning.
‘A big box of exotic matter like a Poole wormhole mouth.’
‘Just the job. The Squeem wrecked the old Poole wormhole transport system, but they left the wormhole mouths in place. There are several still orbiting Saturn. Any one of them will do.’
‘And if we throw one of these things into Rhea—’
‘It will eat up the moon.’
‘That would get rid of them,’ Rhoda said.
‘That it would. And later the residual black-hole-like object would just evaporate away . . . Of course there are other options. The Squeem may be useful. We could use them, as they once used us. A Galaxy-spanning telepathic network—’
‘We don’t need them in the Solar System for that. We have their homeworld.’
‘True.’ Kaser eyed Rhoda. ‘The technology’s in place. The only question remains, do we use it?’