She began to list classes of evidence of vanished cultures. She reminded them that the Goober’s Star system had shown evidence of being mined out, regularised, perhaps by some culture that had vanished long before Ghosts, Qax, Xeelee or humans turned up. Even Anthropocene-era Earth could have destroyed itself in a way that would have been visible to cultures on Alpha Centauri or further out, Jophiel learned now. An all-out nuclear war would have produced a flash of gamma rays visible across interstellar distances, but only lasting a few hours, perhaps. Some of the longer-lasting effects – an atmosphere gone opaque through a nuclear winter, the depletion of ozone and other perturbations of the air – would have lingered, and would have been detectable from afar.
‘We’re probably not recognising all that we see,’ Asher said. ‘Maybe some of those who survive war and conquest go on to some advanced plane of existence we know nothing about. What we don’t see is any sign of a thriving interstellar empire. No lanes of transports, no huge multi-species space liners crossing the stars . . .’
‘Lots of diversity, though, it sounds like,’ Nicola said.
‘Yes – because humans never got here,’ Jophiel said heavily. ‘In this timeline. Not after the Xeelee intervention and the Scattering.’
‘Right,’ Asher said. ‘By now there should have been a wave of human expansion out of the Solar System and the Orion Arm that was called, in some Poole-archive accounts, the Assimilation. A huge disruption, right across the Galactic disc. And an extinction event, if you like. To rival on a Galactic scale the Columbian exchange, when the Europeans of the Discovery Era started to ship slavery, diseases, and rats around the planet.’
Nicola grinned at Poole, not unsympathetically, Jophiel thought. She said, ‘An extinction event, though. Which you seem to have – well, inspired in one timeline, Poole. At least one timeline. But then the Xeelee intervened. Here’s something I’ve heard the crew muttering about, when they’ve seen some of this data. The younger ones, who don’t have our cultural baggage. Who have grown up as refugees. Look – if the Xeelee that invaded the Solar System averted a Galaxy-wide extinction, a bonfire of life and culture, did it do a good thing? By some higher measure of morality. And if so, maybe we’re wrong to try to kill it for its troubles.’
To describe the shocked silence that followed as awkward, Jophiel thought, didn’t begin to cut it. What an astounding swivel of perspective.
‘We are where we are,’ Michael Poole said gruffly. ‘We’ve made our choices. And we just have to continue, that’s all. What else would you have me do? What?’
And even Jophiel, looking into his own simulated heart, had no answer.
With some relief, Asher said, ‘Now for the bigger picture.’
Jophiel stared. ‘Bigger than this?’
‘Oh, yes. Like I said, at least we had some familiarity with what goes on in the spiral arms. Here’s what we didn’t understand so well.’
She waved her hands again.
Now the Galaxy image tipped up, shrank down to the size of a dinner plate – and a wider shell, transparent with a silvery glimmer, materialised around the Galaxy itself. Dwarfing it.
‘Here’s my representation of the Galaxy’s dark-matter halo, on its grossest of scales. We relied a lot on the data compiled by the Gea in the early days, though we have built on that since.
‘You can see most of the dark matter is out beyond the visible edge of the Galaxy – but not all of it. Look, see that silver plane embedded in the disc? There is actually a significant density of dark matter down there within the visible disc, which is, as I’ve said, very thin, comparatively, in itself. How does it get down there? We have records of some very ancient observations of these phenomena, and theories almost as ancient. Some of which we can confirm now, we think.
‘You see, we do know some things about dark matter. We know it’s made of “sparticles”, in the jargon – supersymmetric copies of regular baryonic-matter particles. And we think now that dark matter has its own set of physical laws. Its own forces, like our nuclear, electromagnetic, gravitational forces. The complication is that the dark-matter suite of forces is not the same as ours. We only have one overlap, in fact: gravity. That’s the only way dark matter influences our baryonic universe directly – but that is a pretty significant way. The lack of any further overlap makes dark matter hard even to observe. Hence “dark”.
‘But the existence of those other forces implies structure in the dark-matter realm.
‘You see, it’s just as a baryonic-matter star, say, has structure, coming from a balance between physical forces: gravity, which tends to compress its bulk, and electromagnetic energy from the core fusion, which tends to blow it apart. Similarly dark-matter structures can form from a balance of relevant forces. In particular if you have some equivalent of electromagnetism – a way to radiate energy – then you have a way to cool down. And objects that cool down can collapse down into a gravity well . . .’
And that, Jophiel realised now, was how come there was that fine dark-matter skim within the thin layer of the Galactic disc. Dark matter that had cooled, slowed down, got trapped in the gravity well of the Galaxy disc.
They debated this, questioning and speculating. There was an almost collegiate atmosphere at times like this, Jophiel thought. As if they were a field expedition from some far-distant university. Whereas Max Ward thought the ship should be more like a warship. Jophiel had always suspected that they weren’t going to get anywhere near their objectives without learning, without acquiring a deep understanding of what they were facing and its context. So, collegiate made him happy.
‘But – life?’ Michael Poole broke in. ‘You keep speaking of structure. Are you talking about life in the dark matter? Those big tendrils Flammarion said she saw, reaching down into the Galaxy disc. Life, even mind?’
Harris Kemp, the nearest to a biology specialist they had on board, rubbed his nose doubtfully. ‘Well, maybe. That’s still a heck of a stretch. But how could such things evolve? Or even breed?’
And Nicola’s silver face was suddenly transformed, the mouth open, the eyes wide. Jophiel, startled, thought he had never seen such an authentic human expression on that reconstructed face of Ghost hide.
She disappeared.
Poole and Jophiel shared a glance. Jophiel said, ‘She seems – over-excited. Do you think she’s OK?’
Michael shrugged. ‘She’s suspicious of her own nature. Of herself. She will never be “OK” again. But she has a good brain, in her way . . . I think she’s come up with something, that’s all.’
And Nicola returned. With a box of construction material, or at least a Virtual replica: the big lens that she and Asher had saved from the Ghosts’ station at Goober’s Star.
32
The big lens-shaped box crowded out the suite.
Poole snapped, ‘What in Lethe are you doing, Nicola?’
‘Planning to return a child to its mother . . . I think. That’s too anthropomorphic, but that’s the basic idea.’
Jophiel frowned. ‘What mother? What child? . . . Oh.’ And he saw it, all at once, just as Nicola must have, before him. ‘The photino fish?’
‘Yes! Look, Jophiel, Michael, we should have put the pieces together before. You were there with me.’
‘Where?’
‘In the Sun, Jophiel! In the Sun. Where we discovered the photino fish for ourselves. And again, there they were inside Goober’s Star, where this specimen was taken from. Probably in every star in the Galaxy, for all we know.’
‘So?’
‘So, look at the two places we think we’ve observed dark-matter life. In the halo of the Galaxy, and in the hearts of stars. Huge scale on one hand, tiny cramped confines on the other. Why would dark-matter creatures be found there, in those contrasting places? Unless—’
Asher nodded, excited herself now. ‘I think I’m starting to see it. Unl
ess they needed to be there.’
‘That’s it. Here’s what I’m thinking now. The dark beasts, the big tentacled monsters out in the halo, represent only part of the – life cycle. I’m thinking salmon, and oceans, and rivers. Jophiel, salmon live in the ocean, but they have to go upriver to breed – right? Same here. These big dark-matter cloud-entities live out beyond the Galaxy, but they can’t breed there. Why? I don’t know. Maybe they need density, compression. Because of the information that must be exchanged between parent and offspring? Maybe two clouds couldn’t mate; they would just – intermingle. Something like that.
‘But there are places in the universe, little pits of gravity, where they could squeeze down and find the compression they need.’
‘In the hearts of stars,’ Asher said.
‘Right! We know gravity works on dark-matter creatures; we know they are immune to heat and radiation. So the Galaxy is like a great reef, to them, full of these tight little pits, the gravity wells of stars, where they can deposit their . . .’
‘Their eggs?’
‘Which hatch out to become photino fish, as we called them, swimming around inside the stars, like the Sun. Like larvae. And when they are mature . . .’
Jophiel said, ‘Ah. They hatch out. As if a star was an egg. They fly back up, out of the stars, out of the disc, up into the halo. And – open their wings.’
Asher laughed. ‘Just like salmon swimming up rivers. Like turtles, coming to the beaches to spawn. I love it, Nicola. It’s too beautiful to be wrong.’
‘So now,’ Nicola said, ‘the right thing to do is obvious. We release the . . . larva from that hull-plate pod, that the Ghosts trapped it inside—’
Jophiel. No.
‘No.’ Jophiel snapped out the word.
He looked around, at surprised frowns. He looked at Michael, and got a blank stare back in response. He had surprised himself. But he knew he was right.
‘No,’ he said. ‘I’m sorry. We need to hold on to that pod, for now. I can’t explain . . . Call it intuition.’
Nicola grinned. ‘Virtuals have intuition, do they?’
Jophiel glared at his template. ‘Michael. You need to trust me. It’s important.’ And, he thought, how he wished he felt he could tell Michael of that other Poole, the reality-leak traveller, who seemed to hover over him like a guilty conscience.
Poole stared back at him. He looked oddly lost. Then he nodded curtly. ‘Leave the pod in its store for now, Nicola. After all, we can always release the fish later.’
Asher looked baffled, irritated. ‘Well, you did a good deed, Nicola. Or tried to.’
‘Yes. Don’t spread it around.’
‘So you have it,’ Asher said. Our journey, our ant-like crawl across the Galaxy. Even the fireworks between the Qax and the Ghosts. All against the context of a Galaxy-wide ecology that was so huge in scale we never even noticed it before.
‘Moving on. Here’s what else we saw.’
Jophiel gaped. ‘There’s more yet?’
‘Further out.’
Another wave of her hand, and the Galaxy, dark-matter shell and all, shrank to the size of a toy, of a human hand.
And it was joined in the image by more toys.
More galaxies. Jophiel saw one big spiral that looked like it outmassed the Milky Way itself, and a clutter of others – perhaps two, three dozen, all of them much smaller than the two big dogs of the pack.
‘So,’ Asher said. ‘Looking beyond our own Galaxy, here’s what you get. The Local Group. The big beast is the Andromeda Galaxy, of course. Right now, around two million light years away. That’s not much on the scale of these objects, maybe twenty Galaxy diameters. And in fact, as you probably know, Andromeda and our Galaxy may be heading for a collision, perhaps three, four billion years from now. I mention it as something we might have to deal with, if Michael keeps us plummeting into the future.’ Polite laughter.
(Much later Jophiel would remember this exchange. Asher’s gentle joke. The laughter.)
‘And zooming out further—’
That compact little group shrank down to a detail in a much larger conglomeration of galaxies and galaxy clusters.
‘The Virgo supercluster,’ Asher said. ‘A hundred million light years wide. Hundreds of galaxies. Which come in all sizes and ages, from dwarfs up to monsters about a hundred times our Galaxy’s mass. Some galaxies are younger than ours. Some so old they are nothing but wrecks full of red dwarfs and stellar remnants. As for the scale: I’ll expand again, and again.’
A zoom out. More clusters and superclusters, gathering in threads and planes, in three dimensions.
‘You can see that the Virgo group is itself part of a greater mass, called the Pisces-Cetus supercluster, a billion light years across . . .’
The threads and sparks of light were assembling into an open structure. Now, to Jophiel, the image didn’t look so much like a cosmological picture as something caught under a microscope: the cluster of atoms that made up a base molecule, say, which in turn were threaded on the fragile spiral of a DNA molecule . . .
‘This is the universe on the largest of scales we can observe,’ Asher said.
‘Remarkable,’ Susan Chen said. ‘The cosmos is so empty.’
Nicola shook her head. ‘It looks like a room full of cobwebs.’
‘Well, that’s not a bad analogy.’ Asher pointed out details. ‘Galaxies gather in clusters, which gather into superclusters, and features we call “walls” – these threads and sheets. We think all of this is a product of the way the early universe emerged from the Big Bang. A sea dominated by dark matter, more or less smooth, but with turbulence. And the baryonic matter, the light matter, gatherred in the dips and the cracks.’
Nicola grinned. ‘A universe like the back of a giant turtle, like in some old myths. And the galaxies are like diamond dust scattered on the turtle’s shell, gathering in the folds and pocks . . .’
‘But it isn’t static,’ Asher said. ‘All the galaxies, all of this structure, is in motion.’
Another wave of the hand, and the galaxy pinpoints were colour-coded in a manner obvious for a spacefarer: red for receding, blue for approaching, like Doppler shift.
Almost all of the picture was coloured red, Jophiel saw, startled.
Asher drew the obvious conclusion. ‘You can see that aside from a little random motion, all the galaxies, including our own, and their clusters, are being pulled across space. And this organised flow is on a tremendous scale. All this has been measured before; we are only confirming models themselves thousands of years old.’
‘That,’ said Susan Chen, ‘is a lot of moths. But what is the flame?’
Asher looked at her. ‘This is what we weren’t able to show you before the shutdown.’ She clapped her hands, and the images disappeared, leaving the room feeling dark – and cold, and empty, Jophiel thought, though he was as unreal as those images himself.
And in the darkness, something appeared – Jophiel squinted to see – small, remote, blurred. Surrounded by mist.
Perhaps a torus, tilted up.
A ring.
Jophiel stared, and looked across at Michael Poole.
He, they, had seen this before. Another object enigmatically glimpsed in the amulet of the Silver Ghost.
‘The generation who discovered this – I think it was the twenty-first century, or maybe the twentieth – called it the Great Attractor,’ Asher said softly. ‘The great mass that is drawing in all the galaxies, across the observable universe. They couldn’t see it, but they could infer its existence, its distance and mass, just by looking at your great cloud of moths, Susan. Now we can image it . . . almost.
‘We think this thing is a hundred and fifty million light years away. We think it has as much mass as tens of thousands of galaxies. And we think it, itself, is perhaps ten million light years across.
’ She sketched out the ring shape with her finger. ‘The whole of the Andromeda–Milky Way pair would fit inside that structure.’
‘Structure.’ Michael Poole turned his head sharply. ‘Do you mean an artificial structure? A construct? Ten million light years wide?’ He turned to Jophiel. ‘And we thought our wormholes were big engineering.’
Jophiel asked, ‘What in Lethe is it made of?’
‘Well, we can’t know,’ Asher said a little testily. ‘I’ve had one suggestion that it could be some variant of cosmic string.’
Which, Jophiel knew, was a defect in spacetime itself, a remnant of the initial singularity. Atom-thin, a rope-like flaw whipping through space at near lightspeed, and massive enough to bend spacetime around it . . . ‘Somebody is using that as a building material? But what is this for, Asher?’
‘We can only guess.’ Now Asher, clearly cautious, began to describe measurements made right at the limit of her instruments’ capabilities. ‘For a start,’ she said, ‘there is some very exotic radiation coming from the ring’s central region. We suspect the ring itself isn’t just massive, it may be rotating. And is creating a singularity of some kind at the centre.’
‘Ripping a hole in space,’ Nicola murmured. ‘I admit, I’m impressed.’
‘Also,’ Asher pushed on doggedly, ‘we are seeing what looks like planetbuster-beam radiation backwash, around the central structure . . .’
‘Xeelee,’ Nicola said immediately. ‘Fighting.’
‘And further out still, a dense concentration of dark matter,’ Asher concluded. ‘Seriously dense. All around the ring. And complex, with powerful gravitational fields capable of manipulating masses on a very large scale. I mean, more than stellar masses. Clusters of stars, maybe even dwarf galaxies.’
‘Lethe,’ Nicola said. ‘Huge energies being expended, across a tremendous volume. Masses hurled in at the ring, and planetbuster fire in return. Attack and defence. This is a war zone. Max Ward is going to love it.’
Xeelee Redemption Page 20
