Sarumpaet had struggled for decades to breathe life into this vision, by finding the correct laws that governed the probability of any one graph evolving into another. In the end, he’d been blessed by a lack of choices; there had only been one set of rules that could make everything work. The two grandparents of his theory, imperfect as they were, could not be very far wrong: both had yielded predictions in their respective domains that had been verified to hair’s-breadth accuracy. Doing justice to both had left no room for errors.
Livia said, “Conceptually, that argument is very appealing. But there could still be deviations from the rules — far too small to have been detected so far — that would change the outcome of your experiment completely.”
“So it’s a sensitive test,” Cass agreed. “But that’s not why I’ve proposed it.” They were talking in circles. “If the rules hold, the graph I’ve designed should be stable for almost six-trillionths of a second. That’s long enough to give us a wealth of observations of a space-time utterly different from our own. If it doesn’t last that long, I’ll be disappointed. I’m not doing this in the hope of proving Sarumpaet wrong!”
Cass turned to Darsono, seeking some hint that he might share her exasperation, but before she could gauge his mood, Livia spoke again.
“What if it lasts much longer?”
Finally, Cass understood. “This is about safety? I’ve addressed the potential risks, very thoroughly — ”
“On the basis that the Sarumpaet rules are correct.”
“Yes. What other basis should I have used?” Phoenician astrology? Californian lithomancy? Cass resisted the urge to lapse into sarcasm; there was too much at stake. “I’ve admitted that there’s no certainty that the rules hold in every last untested circumstance. But I have nothing better to put in their place.”
“Nor do I,” Livia said gently. “My point is, we mustn’t over-interpret the success of the Sarumpaet rules. General relativity and quantum field theory confessed from the start that they were just approximations: pushed to extremes, they both yielded obvious nonsense. But the fact that QGT doesn’t — the fact that there is no fundamental reason why it can’t be universally applicable — is no guarantee that it really does stretch that far.”
Cass gritted her teeth. “I concede that. But where does it leave us? Refusing to perform any experiment that hasn’t been tried before?”
Rainzi said, “Of course not. Livia is proposing a staged approach. Before attempting to construct your graph, we’d move toward it in a series of experiments, gradually bridging the gap.”
Cass fell silent. Compared to outright rejection this was a trivial obstacle, but it still stung: she’d worked for thirty years to refine her own proposal, and she resented the implication that she’d been reckless.
“How many stages?”
“Fifteen,” Livia replied. She swept a hand through the vacuum in front of her, and a sequence of target graphs appeared. Cass studied them, taking her time.
They’d been well chosen. At first one by one, then in pairs, then triples, the features that conspired to render her own target stable were introduced. If there was some undiscovered flaw in the rules that would make the final graph dangerous, there could be no more systematic way to detect it in advance.
“It’s your choice,” Rainzi said. “We’ll vote on whichever proposal you endorse.”
Cass met his eyes. The openness of his face was an act of puppetry, but that didn’t mean he was insincere. This wasn’t a threat, an attempt to bully her into agreeing. It was a mark of respect that they were letting her decide, letting her weigh up her own costs, her own fears, before they voted.
She said, “Fifteen experiments. How long would that take?”
Ilene answered, “Perhaps three years. Perhaps five.” Conditions varied, and the Quietener wasn’t perfect. Planning an experiment in QGT was like waiting for a stretch of ocean to grow sufficiently calm that a few flimsy barriers could block the waves and keep out the wildlife long enough to let you test some subtle principle of fluid dynamics. There was no equivalent of a laboratory water tank; space-time was all ocean, indivisible.
In terms of separation from her friends, five years was nothing compared to the centuries she’d already lost. Still, Cass found the prospect daunting. It must have shown on her face, because Bakim responded, “You could always return to Earth immediately, and wait for the results there.” Some of the Mimosans had trouble understanding why anyone who found life in the station arduous would feel obliged to be here in person at all.
Darsono, empathetic as ever, added quickly, “Or we could give you new quarters. There’s a suitable cavity on the other side of the station, almost twice as large; it’s just a matter of rerouting some cables.”
Cass laughed. “Thank you.” Maybe they could build her a new body, too, four whole millimeters long. Or she could abandon her scruples, melt into software, and wallow in whatever luxuries she desired. That was the hazard she’d face every day, here: not just the risk that she’d give in to temptation, but the risk that all the principles she’d chosen to define herself would come to seem like nothing but masochistic nonsense.
She lowered her gaze toward the illusory meadow, laserpainted on her retinas like everything around her, but her mind’s eye conjured up another image just as strongly from within: the Diamond Graph, as she saw it in her dreams. She could never reach it, never touch it, but she could learn to see it from a new direction, understand it in a new way. She’d come here in the hope of being changed, by that knowledge if by nothing else. To flee back to Earth out of fear that she might test her own boundaries more rigorously here, in a mere five years of consciousness, than if she’d spent the same three-quarters of a millennium at home, would be the greatest act of cowardice in her life.
“I’ll accept the staged experiments,” she declared. “I endorse Livia’s proposal.”
Rainzi said, “All in favor?”
There was silence. Cass could hear crickets chirping. No one? Not Livia herself? Not even Darsono?
She looked up.
All seven Mimosans had raised their hands.
Chapter 2
Riding her ion scooter the million kilometers to the Quietener, Cass found herself reveling in the view for the first time in years. The scooter was doing one-and-a-quarter gees, but the couch pressed against her back so gently that she might have been floating. Floating in dark water, beneath an alien sky. Even at half a light-year, Mimosa punched a dazzling violet hole in the blackness, a pinprick ten times as bright as a full moon. Away from its glare, the stars were far too plentiful to suggest constellations; any stick-figure object that she began to sketch between them was soon undermined by an equally compelling alternative, then a third, then a fourth — like a superposition of graphs, each with a different choice of edges between the same nodes. When she’d first arrived, she’d homed in on her own star, watching with a mixture of fear and exaltation as it hovered at the edge of visibility to her thousandth-scale eyes. Now, she’d forgotten all the cues she’d need to find it, and she felt no urge to ask her navigation software to remind her. The sun was no beacon of reassurance, and she’d be seeing it close-up again soon enough.