Timelike Infinity

She went on, 'I mean to accept AntiSenescence treatment here. If I’m offered it, or can buy it. And then—'

' — and then it’s a simple matter of living through fifteen centuries — fifty generations — and waiting for the reemergence of singularity technology. So you can start all over again. Is that what you mean?'

Her smile lingered.

'How can you think in such terms?' he demanded. 'You got to know Michael Poole; after two centuries of life his head was so full of detritus, of layers of experience, that at times he could barely function. You saw that, didn’t you? Why did you think he spent decades, literally, alone in that GUT ship in the cometary halo? And you’re talking, almost casually, about lasting more than seven times as long. How can any purpose endure through such an immense time scale? It’s — beyond the human…'

The girl did not reply, but her smile lingered on, inwardly directed; and Parz, despite his superiority in years to this girl, felt as if he had become something weak and transient, a mayfly, beside the immense, burning purpose of Shira.

* * *

Harry crystallized into the empty couch beside Michael. The image was weak and wavering, the pixels crowding and of uneven size — evidently Harry didn’t have available the processing power he’d used earlier — but there was at least an illusion of solidity, of another presence in the lifedome, and Michael felt grateful enough for that.

Michael lay back in his couch, trying to achieve a state of inner, and outer, relaxation, but he was betrayed by knots of tension in his forehead, his neck, his upper back. He watched the Interface portal blossom open above his head. It spanned most of the dome now. The Spline warship, with the Crab embedded within, was moving along a trajectory that passed the cheek of Jupiter tangentially; and from Michael’s point of view the portal now hung against a backdrop of velvet space, of distant, inhabited stars. The portal’s clean blue-violet geometry — and the burnished-gold effect of the glimmering faces of the tetrahedron, the shadowy reflections of other times and places — were really quite beautiful.

Harry said, his voice a scratch. 'I suppose you do know what you’re doing.'

Michael couldn’t help but laugh. 'It’s a bit late to ask that now.'

Harry cleared his throat. 'I mean, this whole caper has been improvised. I just wondered if you had any clearer ideas about your precise intentions than when, say, you were ramming a lump of comet ice down the throat of a Spline warship from the future.'

'Well, it worked, didn’t it?'

'Yeah, through sheer luck. Only because the Spline was bemused by causality stress, and poor old Jasoft started setting fire to the Spline’s nervous system.'

Michael smiled. 'It wasn’t luck. Not really. What beat the Qax in the end was their own damned complacency. Jasoft was a loophole, a weakness, which they brought back through time with them. If it hadn’t been for Jasoft Parz they would have left some other hole, another Achilles heel for us to exploit. They were so certain they could scrape us out of the Solar System without any trouble, so certain there was nothing we could do to resist them—'

'All right, all right.' Harry threw up his ghostly hands. Come on, Michael. How are we going to destroy the wormhole?'

'I don’t know for sure.'

'Oh, terrific.' Harry’s face turned fuzzy for a moment and Michael imagined more processing power being diverted from the image. Now the image downgraded further, until the illusion of a solid presence in the chair beside Michael was almost lost.

'Harry, is there some problem? I thought we were on routine running until we hit the Interface.'

Harry’s voice came to him through a sea of phasing and static. 'It’s those drones,' he said. 'They’re just too damn smart.'

'I thought you had them under control. You organized them to cast off the eye chamber with Shira and Parz, cut the nerve trunk—'

'Yeah, but I’m not experienced at handling them. Remember they’re not simple remotes; they have a lot of processing power of their own. It’s like — I don’t know — like trying to get work done by a few thousand strong-willed ten-year-olds. Michael, one bunch of them has gone ape. They’ve formed into a raiding party; they’re working through the carcass in search of the high-density power sources. They’re being resisted because the damage they’re doing is going to be detrimental to the functioning of the Spline in the long run. But the resistance isn’t organized yet… and any drone that opposes them is chewed up by those damn little laser jaws of theirs.'

Michael laughed. 'What’s going to be the outcome?'

'I don’t know… The raiders are heading for the Heart of the Spline, now. And I mean the Heart, literally; a city block of power cells and muscle stumps centered around the hyperdrive unit. The area of greatest energy density. If the raiders get through there’ll be hell to pay; the rest of the ship’s systems will be too drained of power to be able to do anything about it, and ultimately they’ll decommission the hyperdrive… But it might not get that far. Other drones are forming up to oppose them. It looks as if there’s going to be a pitched battle, soon, somewhere in the region of the Heart. But at the moment my money is on the rogue, rebel drones; the defenders just haven’t got the leadership—'

Michael cut in, 'Oh, for God’s sake, Harry, will you shut up about the drones? Who cares about the damn drones, at a time like this?'

Harry frowned, blurred. 'Look, Michael, this isn’t a joke. These rebels could disable the hyperdrive out from under us. And you want to use the hyperdrive in your scheme to wreck the Interface, don’t you?'

'What’s the time scale for all this?'

Harry turned away, flickering. 'Twenty minutes for the battle to resolve itself. Another ten for the rebels, assuming they win, to cut their way into the Heart and get to the hyperdrive and other power sources. Let’s say thirty, total, at the outside, before we lose hyperdrive functionality.'

Michael pointed up at the Interface. 'And how long before we’re in the guts of that thing?'

Harry thought for a few seconds. 'Six minutes, tops.'

'Okay, then. That’s why you should forget about the damn drones. By the time they’ve done their worst it will all be over, one way or the other.'

Harry pulled a face. 'All right, point taken. But it doesn’t get you out of explaining to me how you’re going to blow up the Interface portal.' Harry turned his head up to the blue-glowing portal, and — with an evident surge of processing concentration — he produced blue-violet highlights on his Virtual cheekbones. 'I mean, if we simply ram that portal the corpse of this damn ship is going to be cut up like ripe cheese, isn’t it?'

'Right. I doubt if you could do much harm to a structure of exotic matter by smashing it with a lump of conventional material; the density difference would make it as absurd as trying to knock down a building by blowing it a kiss… We’re going to enter the Interface as best we can in this tub—'

'And then what?'

'Harry, do you understand how the hyperdrive works?'

Harry grinned. 'Yes and no.'

'What’s that supposed to mean?'

'It means that I’ve now merged with the residuum of the Spline’s consciousness. And the operation of the hyperdrive is buried in there somewhere… But it’s like working the muscles that let you stand up and walk about. Do you understand me?' He looked at Michael, almost wistfully, his face more boyish than ever. 'The Spline core of me knows all about the hyperdrive. But the human shell of Harry, what’s left of it, knows damn-all. And — I find I’m scared, Michael.'

Michael found himself frowning, disturbed by Harry’s tone. 'You sound — I don’t know — pathetic, Harry.'

'Well, I’m sorry you don’t approve,' Harry said defiantly. 'But it’s honest. I’m still human, son.'

Michael shook his head, impatient with the sudden jumble of emotions he found stirring inside him. 'The hyperdrive,' he said sternly. 'All right, Harry. How many dimensions does spacetime have?'

Harry opened his mouth, closed it again. 'Four. Three space, one time. Doesn’t it? All wrapped up into some kind of four-dimensional sphere—'

'Wrong. Sorry, Harry. There are actually eleven. And the extra seven is what allows the hyperdrive to work…'

The grand unified theories of physics — the frameworks that merged gravitation and quantum mechanics — predicted that spacetime ought to assume a full eleven dimensions. The logic, the symmetry of the ideas, would allow little else.

And eleven dimensions there turned out to be.

But human senses could perceive only four of those dimensions, directly. The others existed, but on tiny scales. The seven compactified dimensions were rolled into the topological equivalent of tight tubes, with diameters well within the Planck length, the quantum limit to measurement of size.

'Well, so what? Can we observe these compactified tubes?'

'Again, not directly. But, Harry, looked at another way, the tubes determine the values of the fundamental physical constants of the universe. The gravitational constant, the charge on the electron, Planck’s constant — the uncertainty scale—'

Harry nodded. 'And if one of these tubes of compactification were opened up a little—'

' — the constants would change. Or,' said Michael significantly, 'vice versa.'

'You’re getting to how the hyperdrive works.'

'Yes… As far as I can make out, the hyperdrive suppresses, locally, one of the constants of physics. Or, more likely, a dimensionless combination of them.'

'And by suppressing those constants—'

' — you can relax the compactification of the extra dimensions, locally, at least. And by allowing the ship to move a short distance in a fifth spacetime dimension, you can allow it to traverse great distances in the conventional dimensions.'

Harry held up his hands. 'Enough. I understand how the hyperdrive works. Now tell me what it all means.'

Michael turned to him and grinned. 'Okay, here’s the plan. We enter the Interface, travel into the wormhole—'

Harry winced. 'Let me guess. And then we start up the hyperdrive.'

Michael nodded.

The Interface portal was immense over them, now; one glimmering pool of a facet filled Michael’s vision, so close that he could no longer make out the electric blue struts of exotic matter that bounded it.

'Three minutes away,' Harry said quietly.

'Okay.' As an afterthought Michael added: 'Thanks, Harry.'

'Michael — I know this won’t, and mustn’t, make a damn bit of difference — but I don’t think there’s any way I can survive this. I can’t function independently of the Spline anymore; I’ve interwoven the AI functionalities of Spline and Crab so much that if one fails, so must the other…'

Michael found himself reaching out to the Virtual of his father; embarrassed, he drew his hand back. 'No. I know. I’m sorry, I guess. If it’s any consolation I’m not going to live through it either.'

Harry’s young face broke up into a swarm of pixels. 'That’s no consolation at all, damn you,' he whispered distantly.

The Interface was very close now; Michael caught fugitive reflections of the Spline in that great, glimmering face, as if the facet were some immense pool into which the warship was about to