‘Like a lure?’
‘Neutron stars are common enough, but they’re still exotic; especially from the point of view of a culture just achieving the capability for starflight. It was guaranteed that the Amarantin would be drawn here through sheer curiosity.’
‘They weren’t the last, were they?’
‘No, I don’t suppose they were.’ Sylveste drew a breath. ‘Do you think we should go back, while we still can?’
‘Rationally, yes. Is that enough of an answer for you?’
They pushed forward.
‘Take us towards the light first,’ Calvin said, minutes later. ‘I want to see it closer. It seems — this is going to sound stupid — but it seems somehow stranger than the other thing. If there’s one thing I’d choose to die having seen up close, I think it’s that light.’
‘That’s how I feel,’ Sylveste said. He was already doing what Calvin had suggested, as if the intention had sprung from his own will. What Calvin said was right; there was indeed something deeper about the strangeness of the light; something more profound, older. He had not been able to put that feeling into words, or even properly acknowledge it, but now it was out in the open, and it felt right. The light was where they had to go.
It was silvery in texture; a diamond gash in the fabric of reality, simultaneously intense and calm. Approaching it, the orbiting jewel (stationary now, in this frame) seemed to dwindle. Smooth pearly radiance surrounded the suit. He felt that the light should hurt his eyes, but there was nothing except a feeling of warmth, and a kind of slowly magnifying knowing. Gradually he lost sight of the rest of the chamber and the jewel, until he seemed to be enveloped in a blizzard of silver and whiteness. He felt no danger; no threat; only resignation — and it was a joyous resignation, bursting with immanence. Slowly, magically, the suit itself seemed to turn transparent, the silver luminance bursting through until it reached his skin, and then pushed deeper, into his flesh and bones.
It was not quite what he had been expecting.
Afterwards, when he came to consciousness (or descended to it, since it seemed that in the hiatus he had been somewhere above it), there was only understanding.
He was back in the chamber again, some distance from the white light, still within the rotating frame of the jewel.
And he knew.
‘Well,’ Calvin said, his voice as unexpected and out-of-place in the tranquillity that followed as a trumpet blast. ‘That was some trip, wasn’t it?’
‘Did you… experience all that?’
‘Put it this way. That was weirdest damned thing I’ve ever felt. Does that answer you?’
It was. There was no need to push beyond that; no need to convince himself further that Calvin had shared all that he had felt, or that for a moment their thoughts — and more — had liquefied and flowed indivisibly, along with a trillion others. And that he understood perfectly what had happened, because in the moment of shared wisdom, all his questions had been answered.
‘We were read, weren’t we? That light is a scanning device; a machine for retrieving information.’ The words sounded perfectly reasonable before he said them, but in the saying of them he felt he was expressing himself poorly, debasing the thing of which he spoke by the crudity of language. But for all the insights he had felt in that place, his vocabulary had not been enlarged enough to encompass them. And even now they seemed to be fading; the way a dream’s magical qualities seemed to wither in the first few seconds of waking. But he had to say it, to at least crystallise what he felt; get it recorded by the suit’s memory for posterity, if nothing else. ‘For a moment I think we were turned into information, and that in that instant we were linked to every other piece of information ever known; every thought ever thought, or at least ever captured by the light.’
‘That’s how it felt to me,’ Calvin said.
Sylveste wondered if Calvin shared the increasing amnesia he felt; the slow fading of the knowing.
‘We were in Hades, weren’t we?’ Sylveste felt his thoughts stampeding at the gates of expression, desperate to be vocalised before they evaporated. ‘That thing isn’t a neutron star at all. Maybe it was once, but it isn’t now. It’s been transformed; turned into a…’
‘A computer,’ Calvin said, finishing the sentence for him. ‘That’s what Hades is. A computer made out of nuclear matter, the mass of a star devoted to processing information, storing it. And this light is an aperture into it; a way to enter the computational matrix. I think for a moment we were actually in it.’
But it was much stranger than that.
Once, a star with a mass thirty or forty times heavier than Earth’s sun had reached the end of its nuclear-burning lifetime. After several million years of profligate energy-expenditure the star had exploded as a supernova, and in its heart, tremendous gravitational pressure had smashed a lump of matter within its own Schwarzschild radius, until a black hole had been formed. The black hole was so named because nothing, not even light, could escape from its critical radius. Matter and light could only fall into the black hole, thereby engorging it towards greater mass and greater attractive force; a vicious circle.
A culture arose that had use for such an object. They knew a technique whereby a black hole could be transformed into something far more exotic, far more paradoxical. First, they waited until the universe was considerably older than when the black hole had been formed; until the predominant stellar population consisted of very old red-dwarf stars, stars which were barely massive enough to ignite their own fusion fires. Next, they shepherded a dozen of these dwarves into an accretion disk around the black hole and slowly allowed the disk to feed the hole, raining starstuff onto its light-swallowing event horizon.
This much Sylveste understood, or could at least deceive himself into thinking that he understood. But the next part — the core of it — was much harder to hold in his mind, like a self-contradictory koan. What he grasped was that, once within the event horizon, particles continued to fall along particular trajectories, particular orbits which swung them around the kernel of infinite density which was the singularity at the black hole’s heart. Falling along these lines, time and space began to blend into one another, until they were no longer properly separable. And — crucially — there was one set of trajectories in which they swapped places completely; where a trajectory in space became one in time. And one subset of this bunch of paths actually allowed matter to tunnel into the past, earlier into the black hole’s history.
‘I’m accessing texts from the twentieth century,’ Calvin murmured, seemingly able to follow his thoughts. ‘This effect was known — predicted — even then. It seemed to follow from the mathematics describing black holes. But no one knew how seriously to take it.’
‘Whoever engineered Hades had no such qualms.’
‘So it would seem.’
What happened was that light, energy, particle-flux, wormed along these special trajectories, burrowing ever deeper into the past with each orbit around the singularity. None of this was ‘evident’ to the outside universe since it was confined behind the impenetrable barrier of the event horizon, and so there was no overt violation of causality. According to the mathematics which Calvin had accessed, there could be none, since these trajectories could never pass back into the external universe. Yet they did. What the mathematics had overlooked was the special case of the tiny subset-of-a-subset-of-a-subset of trajectories which actually carried quanta back to the birth of the black hole, when it collapsed in the supernova detonation of its progenitor star.
At that instant, the minute outward pressure exerted by the particles arriving from the future served to delay the gravitational infall.