Schild’s Ladder

Tchicaya heard someone clear their throat, nervous and tentative, reluctant to break the spell. He turned away from the console, curious and slightly annoyed, wondering what anyone thought they could add to this extraordinary sight with words. But the crowd moved respectfully away from the speaker, making space as if in encouragement.

It was Umrao, a recent arrival from Nambu who Tchicaya had only met once. He looked around shyly, even more nervous now that he had everyone’s attention.

He said, "That’s not particle propagation, but it’s something I’ve seen before, in simulations. It’s persistence, and replication, and interdependence. It’s not a superposition of a billion different vacua — or if it is, that’s only one way to describe it, and I don’t believe it’s the best.

"It’s a biosphere. It’s an ecology. Right down at the Planck scale, the far side is crawling with life."

Chapter 11

Tchicaya said, "We should tell them, now! Take them all the evidence. No, no — better, teach them Yann and Branco’s method, and let them probe the far side for themselves. Then they’ll know they’re not being cheated with some kind of elaborate simulation."

Hayashi groaned. "And then what? They convince themselves that they’re now facing the Virus That Ate Space-Time. While we’ve surrendered our sole advantage."

Pacing the ship, unable to sleep, Tchicaya had run into Suljan and Hayashi. When a casual exchange of views in the corridor had come perilously close to disclosing all the latest discoveries, he’d accompanied them to the Yielders' cafeteria, which was supposedly secured against listening devices. Other people passing through had become entangled in the debate.

Rasmah said, "I agree. This isn’t going to sway anyone. Even if they’re willing to interpret this as evidence for Planck-scale biota, and even if that destroys all their preconceptions about the Mimosan vacuum…if you didn’t care that much about far-side physics, why should you care about far-side microbiology?"

Yann’s icon appeared, seated beside her. "Microbiology? These organisms are a few hundred Planck lengths wide: about ten-to-the-minus-thirty-three meters. This is vendekobiology."

Suljan picked up a mug and raised it threateningly. "What are you doing here? This is where the real people come, to metabolize in peace."

Yann said, "My mistake. I thought you might be sitting around singing the praise of everyone who helped win you a glimpse of the far side. But I can see you’re more interested in getting in some valuable belching and farting time."

Hayashi reached over and slapped Suljan on the back of the head. "You’re an oaf. Apologize."

"Ow. It was a joke!" He turned to Yann. "I apologize. I’m in awe of your accomplishments. I’m already working on an ode to your sacred memory."

Umrao looked embarrassed by all the bickering going on around him. He said, "I suppose we need more evidence if we’re going to convince the skeptics, but for what it’s worth, I’ve been doing some simulations." He summoned graphics, floating above the table. "The mix of replicators is probably not the same throughout the far side. There are other possible equilibria, other population mixtures that look more or less stable — and that’s just changing the relative numbers of the species we’ve seen, not accounting for entirely different ones." The images showed both a graph-level view of these teeming communities of organisms, and a higher-level map of a possible set of neighboring regions.

"The transition zones tend to be quite sharp, and sometimes they just advance relentlessly in one direction at a constant velocity, like the border itself. But there are other situations where an intermediate mix of species forms in a narrow layer, and it stops either side from invading the other."

Tchicaya seized on this. "A kind of internal freezing of the border?"

Umrao nodded. "I suppose you could think of it like that. Except that our side of the border is completely sterile, so it’s not really subject to the same effects."

"You don’t think we could create a layer population like these, that worked with one side unpopulated?"

Umrao thought for a while. "I couldn’t say. For a start, these are simulations, so I’m not even sure that any of this happens in reality. And we’d need to understand many things much more thoroughly before we set out to engineer a layer population with particular properties."

Suljan said, "Screw it up, and the border might just move faster."