‘Part of the reason we’re here today,’ continued Fowler, ‘is to do with the consequences of the unique physics existing within the wormholes, and you’re going to have to forgive me if I go over some points you may already be very familiar with. Mr Kaur, Mr Fairhurst, this being your first time here, would you say you’re reasonably au fait with wormhole physics?’

‘In the very broadest details,’ Kaur replied.

Fairhurst laughed and shrugged his shoulders. ‘If I’d known there’d be a test, I’d have done some homework.’

Fowler nodded. ‘I’ll try and keep it simple, then. As you know,’ he glanced quickly around the table, ‘the colonies were founded by starships travelling at close to the speed of light, each carrying inside it one end of a wormhole linking it back here to the Moon. However, the way time flows within the wormholes means we can step through to a new star system within months of launching a starship – even though, within our own time-frame back here at home, that starship hasn’t yet arrived at its destination.’

‘I’ll have to admit I’ve never exactly been clear on just how that works,’ said Fairhurst, leaning forward.

‘The ce is in the name we use to describe the wormholes,’ said Amanda. ‘CTC means “closed timelike curve”, right?’

Fairhurst nodded.

‘Well,’ Amanda continued, ‘CTC is just a fancy word for time travel. When we send one end of a wormhole to another star, time on board the ship carrying it moves extremely slowly, relative to the outside universe. But, because of the wormhole link on board, we can walk through the wormhole and on to the deck of that ship any time we like, throughout the journey, since the flow of time within the wormhole remains contiguous with its point of origin.’

She tapped a finger on the table in front of her. ‘It essentially allows you to step decades into the future, since the time-frame on board the starship is such that anyone who remains on board throughout its journey is going to experience a transit time of only a few months. So long as the far end of the wormhole is moving at relativistic speeds, it’s a time machine as well as a shortcut across the universe.’

Fairhurst nodded uncertainly. ‘I never understood why we can’t see the wormholes from the outside. I mean, if they go all that way across space, we should be able to see them, shouldn’t we?’

Fowler barely managed to suppress a grin at the look on Amanda’s face.

‘That’s because the wormholes don’t pass through the intervening space at all,’ she explained patiently. ‘They tunnel through hyperspace instead, outside of the physical constraints of our universe.’

Fairhurst looked none the wiser. ‘Please tell me all of this has something to do with why we’re here.’

Fowler nodded to Inez. ‘If you would, Anton.’