The Arrows of Time

‘But as far as we know, there is no such crater.’ Agata met his gaze openly, trying to reassure him of her sincerity: she wasn’t playing some verbal game just to annoy him. ‘There is no crater, because if we saw it, we wouldn’t choose to make it. Esilio can’t force our hand; whatever happens has to be consistent with everything, including our motives.’

Ramiro said, ‘It can’t force our hand, but there could still be an accident.’

‘That’s true. But if we saw such a crater, we wouldn’t even go near it with the explosive.’ Agata would have liked to have taken comfort from the fact that there were no signs at the landing site of any future accident, but if the blast was capable of imposing its own arrow that meant nothing.

Ramiro’s hostility wavered. ‘I don’t know how to think about any of this,’ he admitted. He ran a hand over his face. ‘If the plants can’t bring their arrow to Esilio, why should a bomb do any better?’

‘The roots of a plant aren’t entirely passive,’ Azelio replied, ‘but they do rely on the state of the soil. I don’t think the bomb going off will rely on anything like that.’

‘But in Esilian time,’ Ramiro protested, ‘all the soil we’re supposedly going to make with this bomb has to mesh perfectly with a backwards explosion in such a way that it forms a solid rock. How likely is that?’

‘How likely are the alternatives?’ Agata countered. ‘How likely is it that the explosive will fail to detonate? How likely is it that we’ll allow it to explode in an existing crater instead – just to pander to Esilio’s arrow?’

‘Don’t ask me,’ Ramiro replied bitterly. ‘I only live here.’ Tarquinia reached over and squeezed his shoulder.

Agata said, ‘I can’t predict anything with certainty either, but surely it’s worth doing the experiment.’

Azelio turned to Tarquinia. ‘You think you can extract the explosive safely?’

Tarquinia phrased her reply carefully. ‘I’m as sure as I can be that Verano wouldn’t have allowed anything on the Surveyor that could kill us from a bump or a broken connection. Whether I manage to set it off anyway is another question.’

They spent three more chimes talking over the details, then Tarquinia called for a vote.

Ramiro’s gloom had given Agata pause. Even if the plan succeeded, he might well end up back on the Peerless warning his fellow anti-messagers that the crops counted for nothing when Esilio itself would rot their minds. Why should she risk her life if it would make no difference to the fate of the mountain?

Azelio said, ‘I’m for it.’

Tarquinia followed him quickly. ‘I am too.’

Ramiro was silent. Agata willed him to mutter a surly veto, sparing her the need to make a decision, but having advertised his confusion already he kept his resolve much longer than she could.

‘I’m for it,’ she said, unsure now if she had any better reason than her wish to see Azelio hopeful again.

Ramiro stared at the floor. Agata felt a twinge of sympathy for him: he’d come here with nothing but good intentions, hoping to grant both of the warring parties a chance to live exactly as they wished. It was not his fault that Esilio wasn’t so accommodating.

‘I’m for it,’ he said finally. ‘If we baulk at the risk we could still get killed by a Hurtler on the way back – but we can’t go back without trying everything. If people can survive here, they need to know.’

Tarquinia said, ‘Right.’

As she rose from her couch Ramiro added, ‘To be honest, though, there’s a better reason to do this than anything it can tell us about the crops.’

Agata was confused. ‘What’s that?’

Ramiro said, ‘The look on Greta’s face when we tell her exactly what we did with her beautiful bomb.’

Agata sat in the tent, wearing her helmet so she could hear the audio link clearly over the noise of the wind. Every chime or so the footfalls and gentle clanking echoing in the empty engine cavity gave way to the bone-shaking whine of hardstone being drilled. Tarquinia was making holes in the beam, hunting for the bomb.

Agata pictured the scene as she’d left it, with mirrors angled into the cavity to bring in as much Esilian sunlight as possible. But even the safety lights in the cabin above would be off now, leaving Tarquinia to work with nothing but the view through the time-reversed camera. Exposing the bomb to ordinary light might trigger a tamper-prevention device, but it wouldn’t have made much sense to include the means to detect time-reversed light, when any act of sabotage had been expected to take place close to the Peerless, where the only source would have been distant starlight.

The camera could amplify the faint image obtained by a periscope inserted in each inspection hole, with sunlight introduced by a second mirrored tube. But so far, all Tarquinia had been able to report was that there were dozens of baffles inside the hollow beam, blocking the view along its length, leaving her with no way to proceed but trial and error.