The Arrows of Time: Orthogonal Book Three (40 page)

Pio leant back and examined her appraisingly. ‘Detours really do work the way they taught us in school,’ he marvelled. ‘Twelve years in that box. How did you stay
sane?’

‘The time passed quickly,’ she said. ‘After the first year.’

‘I can’t say the same, though maybe with the ratios it almost evens out.’ He buzzed suddenly. ‘Cira told me about your big discovery. The ancestors don’t burn, we
don’t wipe ourselves out – what could be better than that?’

‘People acting on it,’ Agata replied. ‘I thought I’d come back to find that everyone had buried their differences.’

‘Not yet.’

Agata didn’t want to start interrogating him about his views on the disruption, but it would seem strange if they didn’t discuss it at all. ‘Do you think the Councillors are
going to pull the plug?’

‘Why would they do that?’

‘They’ve seen the problems that the system’s created,’ she said. ‘We can’t spend the next six generations stuck with the same technology.’

‘But how would they explain the shutdown afterwards, without admitting that they’d planned it all along?’ Pio wondered.

‘They could claim that there’d been some kind of minor impact,’ Agata suggested. ‘With just the right size and trajectory to take out all twelve channels at once, but do
no real damage elsewhere.’

‘All of which they’d more or less guessed, of course. But lacking proof, they couldn’t announce it officially.’ Pio inclined his head. ‘It’s possible, I
suppose. We’ll know soon enough.’

‘Yes.’

Pio changed the subject. ‘Are you going to see Cira?’

‘I don’t think so.’ Agata supposed it might sound suspicious that she was prepared to reconcile with Pio but not her mother. But she wasn’t a good enough actor to pull
off that encounter, and Cira would have much less motivation to play along. ‘If she’s stood by you, that’s admirable, but I think she and I reached the point a long time ago where
we’ll be happier if we stay out of each other’s way.’

‘I understand.’

‘Can I bring you anything?’ she asked. ‘They let you have books, don’t they?’

‘I can always use more paper and dye,’ Pio said. ‘I’m writing a book of my own.’

‘What kind of book?’ Agata couldn’t help mocking him a little. ‘Surely there’s no need for a migrationist manifesto now?’

‘It’s a history of women and men,’ he replied.

‘You mean the discovery of shedding – that kind of thing?’

‘More or less. You can read it when it’s finished, if you like.’

Agata couldn’t imagine what he thought he could add to the version in the archives, but if he had a project to help him pass the time that could only be a good thing.

When the guard returned to fetch him, Pio leant across the desk and executed an awkward hug. As he drew back, Agata was still trying to memorise the sensation of his palm on her shoulder.

‘Will I see you again?’ he asked.

‘Of course,’ she replied. The guard looked amused; apparently not in the next five stints.

Agata sat at the desk for a while, self-consciously pensive, her palms resting on her thighs as she passed copies of Pio’s tightly scrawled instructions back and forth between the two
hidden patches of skin.

The food hall was close to the rim of the
Peerless
, and even at the second bell it was crowded. Agata entered and queued at the counter, trying to remain unfazed as
she noticed people looking her way twice, probably recognising her from the archival image of the
Surveyor
’s return. At least their faces showed a flicker of surprise, proving that
they wouldn’t make so much of the encounter that they let themselves know about it in advance.

She’d barely slept the night before, and then as she’d prepared to leave her apartment her console had beeped and offered up a message from her future self:

I still don’t agree.

It would be sent three stints before the disruption; that didn’t quite prove that she’d be walking free right to the end, but it was more reassuring than absolute
silence. And if the meaning was opaque to her at present, she could only hope that anyone spying on her would find the lack of context unremarkable. There was no reason for anyone’s private
messages to spell out every detail of the dilemmas they were intended to resolve. The bandwidth quotas weren’t infinite: gnomic brevity would generally be a virtue, not a sign that the sender
had something to hide.

When her turn came at the counter she asked for two plain loaves; she’d discovered after the welcoming party that her gut no longer appreciated fresh spices. She carried the food to the
corner farthest from the entrance, where an awkwardly placed cooling vent discouraged most diners. The present crowd left few enough alternatives for her choice not to seem too perverse.

She sat on the floor and ate slowly, her front eyes on her food, her rear gaze to the wall.

She was halfway through the second loaf when a man addressed her. ‘Did you drop these?’ Agata looked up. There were three coins on his outstretched palm; she squinted at them,
memorised their value, then said, ‘No, they’re not mine.’

‘Sorry to have troubled you.’

Pio hadn’t told her how long she should wait, so as soon as she’d finished eating she left the hall and headed for the address indexed by the coins’ denominations. The area
wasn’t familiar to her, but as she ascended the stairs towards the axis and then dragged herself along the corridor towards her destination, the smooth texture of the rock beneath her feet
and the red tunnel of the moss-lit walls were enough to induce an ache of recognition. The death of every traveller save a handful of evacuees was beyond her power to imagine, but she’d come
as close as anyone alive to feeling the absence of the mountain itself. If she needed a vision of the loss she was fighting to prevent, she could think of the
Peerless
retreating into the
distance, shrinking to a dark speck against the stars and then vanishing.

Outside the door, she hesitated, but she’d have to trust Pio’s comrades to have chosen an appropriate level of precautions, and the innovation block to have kept the Council from
automatically tracking everyone, everywhere. She knocked firmly, and after a few pauses the door swung open and a man invited her into the apartment.

‘My name’s Giacomo,’ he said.

‘I’m Agata.’ She closed the door behind her. ‘Can we talk freely?’

‘Absolutely,’ Giacomo assured her.

There was no point in prevaricating. ‘I want to help shut down the messaging system,’ she said. ‘We have a dozen and six small machines out on the slopes, capable of moving
along the rock and flying for short distances. If you can tell us exactly where to send them, we can use them to occult the orthogonal stars for all of the channels.’

Giacomo hesitated before replying, but only as much as politeness required. He must have had years to consider her offer.

‘The system uses light from the entire orthogonal cluster,’ he said. ‘It’s not a matter of one star per channel. To shut it down, you’d need to blot out half the
sky from twelve different vantage points.’

‘The entire cluster?’ Agata had always pictured a single star as the light source. When Medoro had first raised the idea with her, he’d started with a thought experiment where
a distant object passed in front of a time-reversed star – and if the object had to be remote enough for the time the light spent in transit to be significant, it could hardly block out
anything larger. But once you folded up the light path with mirrors, the same constraints no longer applied.

‘The optics gathers light from all directions visible from the base of the mountain,’ Giacomo explained. ‘Or sends it out, if you want to talk in terms of our arrow, but
it’s easier for me to imagine the whole thing working backwards. All that each channel needs is a reliable light source that it can block or reveal with a shutter. Combining all the light
from across the cluster makes the source brighter and more dependable.’

‘And less vulnerable to sabotage,’ Agata conceded. She’d convinced herself that the Councillors would be relying on secrecy, each one guarding the coordinates of their chosen
star. Instead, they’d adopted a robust solution that could not be undermined merely by the revelation of a couple of numbers.

‘But your machines will still be very useful,’ Giacomo said encouragingly. ‘I can promise you that.’

‘How?’

‘They’ve been part of our plan for years. They won’t be able to block the channels with their presence alone, but they can still carry explosives to the sites where
they’re needed.’

‘We’re not doing it!’ Agata declared angrily. ‘We’re not going to be accomplices to these murderers. We’ll have to find another
way.’

Ramiro said, ‘There might not be another way.’

‘So now you’re happy to kill people?’ Agata stared at him in disgust.

‘We don’t know that there’ll be casualties.’ Ramiro paused, dismayed by the weakness of this disclaimer. But he pressed on. ‘If Giacomo’s group sets off a
blast beside each light collector that’s just large enough to shatter it, that need not do a whole lot of damage further down.’

Agata was unmoved. ‘So you’ll trust the same fanatics who killed seven people in the camera workshop to be scrupulous now about sparing lives?’

Ramiro spoke bluntly. ‘Whoever attacked the workshop intended to kill those instrument builders – they were targeting people’s skills as much as the machinery. We
shouldn’t assume that Giacomo’s group have any other goal beyond damaging the system itself.’

‘Why would a single technician even be down there, when they all know the disruption’s coming?’ Tarquinia added. ‘Whether they’re expecting a bomb or a meteor,
it’s an obvious place to avoid.’

‘And what if the damage goes deeper?’ Agata argued. ‘What if the hull is breached?’

‘Most of that area’s taken up with the cooling system for the engines,’ Tarquinia said. ‘That’s self-contained: if it’s damaged, it’s not going to vent
any of our own air to the void.’

‘The light paths run all the way along the axis,’ Agata replied. ‘Blow up the optics on the outside, and there’s no guarantee that you won’t be connecting every
channel straight to the void.’

‘But they’ll be sealed, for sure,’ Ramiro protested. ‘To keep contaminants out of the beams.’

‘Sealed along the whole length of the mountain, well enough to hold against a vacuum?’ Agata’s tone was scathing. ‘All twelve, with no chance of failure?’

Tarquinia said, ‘If the Councillors want to impress voters with the value of foresight, they’ll have spent all their resources for the last three years reinforcing every scant of
those tubes.’

Agata buzzed sardonically. ‘You mean the resources left once every Councillor had ensured that they could personally survive a meteor turning the mountain into rubble?’

Ramiro glanced at his console. Since he’d been back in his apartment he’d been wondering if his resolve to shun the system would ever falter, but now he felt an almost physical
craving for the very thing he’d always reviled.

‘What does Giacomo say?’ he asked Agata. ‘Is he expecting us to cooperate?’ The answer to that might not settle things as clearly as a message from his future self
– but even if it rang false and he concluded that Giacomo was lying, he would still have arrived at a prediction of sorts.

‘I thought you didn’t want to know the future,’ Agata replied.

‘If Giacomo knew for sure that we wouldn’t go along with this . . .’ Ramiro struggled to classify the consistent possibilities. ‘He’d still have to put the proposal
to us, wouldn’t he? Or how could he know that we’d refuse?’

Agata said, ‘He claims that his people do use the occulters. Make of that what you like.’

Ramiro waited for this revelation to bring him clarity, but it was no help at all. He could believe that, in the end, he would decide that the bombing was the lesser of two evils compared with a
meteor strike. But if he’d heard the opposite claim he would have concluded that he’d convince himself that with the saboteurs left weaponless, the Council would step in and do the deed
themselves. Neither answer would have rung so false as to convince him that it couldn’t be true.

‘What do you think we should do?’ he asked Agata.

She said, ‘I’m going to find a way to shut down the system without blowing anything up.’

‘How?’

Agata hummed disdainfully. ‘Do you seriously expect me to have the answer already?’

Tarquinia said, ‘Not how to shut it down, but how to find a way.’

‘The innovation block isn’t an absolute principle.’ Agata was defiant. ‘Maybe in the long term it’s impossible to keep anything secret – but the closer we get
to the disruption, the easier it should be to keep my ideas to myself until it’s impossible for them to leak into the past.’

Ramiro said, ‘And the closer you get to the disruption, the less time you’ll have to come up with something workable and put it into practice. That’s a slender thread on which
to hang the fate of the mountain.’

‘Perhaps,’ Agata conceded. ‘But why did the ancestors send me that message, if not to give me the courage to try? They couldn’t tell me what the method would be, but they
could strengthen my resolve to find one.’

‘You think the ancestors were speaking to you personally?’ Ramiro glanced at Tarquinia, wondering if she’d finally break her silence and admit to the forgery.

‘When the rock face was exposed,’ Agata replied, ‘I didn’t think the message was for me at all. I didn’t think I needed it. But the ancestors won’t choose
that site lightly. They’ll know our whole history, they’ll know how all the pieces of it fit together. They’ll know exactly how and why we came through this unscathed. If the
disruption had a natural cause, why wouldn’t they simply tell us that? It’s the fact that they
can’t
reveal the details that reveals the nature of the event.’

Ramiro wasn’t sure how much his own face was revealing. ‘Go ahead, then,’ he urged her. ’See what you can come up with.’ It couldn’t do any harm.