Ian McDonald - River of Gods

“Nutes,” Lisa Durnau yelled over the sea of heads. The hydrofoil staff had sealed and barred the gate to the jetty and were lifting money from the hands thrust through the bars to permit refugees to slip aboard. She guessed they were halfway to the gate but she was tiring.

“Nutes,” Thomas Lull shouted back. “It’s a long shot, but if I’m right, it’s the missing piece.”

To what? Lisa Durnau wanted to ask but the crowd surged. The hydrofoil was filling by the second. Refugees were waist deep in the Ganga, holding babies, children up to the boat crew who pushed them ungently back with landing poles. Thomas Lull pulled Lisa Durnau close to him. They fought to the head of the line. The steel gate opened, the steel gate clanged shut. Bodies jammed against the grating.

“Got any green?”

A search of her bag threw up three hundred in traveller’s cheques. Thomas Lull waved them in the air.

“US dollars! US dollars!”

The steward beckoned him forward. His crew shoved back the clingers-on.

“How many how many?” Thomas Lull held up two fingers. “In in.”

They squeezed through the barely open gate, up the gangplank and onto the hydrofoil. Ten minutes later, grossly overloaded, it pulled away from the still-growing crowd on the ghats. To Lisa Durnau, peering through the streaky window, it looked like a blood clot.

In the overcrowded lounge she pushes the Tablet towards Thomas Lull. He thumbs through the pages of data from the Tabernacle.

“So what is it like in space, then?”

“Smelly. Tiring. You spend most of your time out of your head and you never actually get to see anything.”

“Bit like a rock festival. First thing strikes me about this, you assume it’s an artefact of an extraterrestrial civilization.”

“If the Tabernacle is seven billion years old, then why don’t we see the aliens who built it everywhere we look?”

“A variant on the Fermi Paradox—if aliens exist, then where are they? Let’s work through this: if we posit the Tabernacle builders an expansion rate of even one-tenth percent of the speed of light, in seven billion years they would have colonised all the way to the Sculptor Galaxy group.”

“There’d be nothing but them.”

“But all we find is one shitty little asteroid? I don’t think so. Subsidiary point, if it is almost twice as old as our solar system.”

“How did they know we’d be here to find it?”

“That this swirl of Stardust would one day turn into you, me, and Aj. I think we can dismiss that theory. Conjecture two: it’s a message from God.”

“Oh come on, Lull.”

“I’d lay better than evens it’s been whispered at the White House prayer breakfast. The end of the world is at hand.”

“Then that’s the end of the rational worldview. It’s back to the Age of Miracles.”

“Exactly. I like to think my life as a scientist has not been a complete waste. So I’ll stick to theories that have some nugget of rationality in them. Conjecture three, another universe.”

“That thought occurred to me,” says Lisa Durnau.

“If anyone knows what’s out there in the polyverse, it should be you. The Big Bang inflates into a set of separate universes all with slightly differing physical laws. The probability is virtually one hundred percent that there’s at least one other universe with an Aj, a Lull, and a Durnau in it.”

“Seven billion years old?”

“Different physical laws. Times runs faster.”

“Conjecture four.”

“Conjecture four: it’s all a game. Rather, it’s all a simulation. Deep down, physical reality is rules and the application of rules, those simple programmes that give rise to incalculable complexity. Computer virtual reality looks exactly the same. I’ve only been saying this all my life, L. Durnau. But here’s the rub. We’re both fakes. We’re reruns on the final computer at the Omega Point at the end of space-time. The probabilities are always going to be in favour of our reality being a rerun rather than the original.”

“And bugs are appearing in the system. Our mystery seven-billion-year-old asteroid.”

“Implying some imminent plot development for The Sims.”

“You’re not supposed to see the Great and Powerful Oz,” says Lisa Durnau. “We’re definitely not in Kansas any more.”

The chai-wallah passes, swinging his stainless steel urn, chanting his mantra: chat, kafi . Thomas Lull takes a fresh cup.

“I don’t know how you drink that stuff,” Lisa says.

“Conjecture five. For a mysterious alien artefact, it’s a bit clunky. I’ve seen more convincing SFX on Town and Country .”

“I get what you’re saying here. It looks like we built it—if we wanted to send some kind of message to ourselves.”

“One you can’t ignore—an Earth-crossing asteroid, and then make it move out of the way.” Lisa Durnau hesitates. This is beyond blue-sky. “From our future.” “There’s nothing here I don’t see us achieving in a couple of hundred years.”

“It’s a warning?”

“Why else send something back, unless you need to change history pretty damn bad? Our umpteen-great-grand-Lulls and Durnaus have run into something they can’t deal with. But if they gave themselves a couple of hundred years’ head start.”

“I can’t imagine what they’re up against if they can send objects through time and they’re still on the ropes.”

“I can,” says Thomas Lull. “It’s the final war between humans and aeais. We’d be up against Generation Tens by then—one hundred million times the capability of a Gen Three.”

“That means they would operate on the same level as the Wolfram/Friedkin codes that underly our physical reality,” Lisa Durnau says. “In which case.”

“They could directly manipulate physical reality.”

“You’re talking magic here. God, magic. Jesus, Lull. I’ve objections. One: they send it back seven billion years?”

“A gravitational anomaly stirred the dust nebula that became this solar system. A passing black hole would make a dandy anchor point for a timelike wormhole. At least they would know we would be here.”

“Very good, Lull. Try this one. Objection two: as messages go, it’s a bit obtuse. What’s wrong with a simple help we are getting fucked over by Artificial Intelligences with the powers of gods?”

“What do you think the effect of that would be? By the time we work it out, we’ll be ready for what the Tabernacle has to say to us.”

“You’re not convincing me, Lull. Even with Generation Tens and wormholes and the fact that the act of sending a warning splits us off into a universe where we get the head start but dooms them in their universe. even with all that, why the hell are you, me, and an eighteen-year-old girl who can talk to machines so important?”

Thomas Lull shrugs, that maddening, grinning, don’t-know-don’t-care gesture that had always the power to infuriate Lisa when she argued his speculations down in sessions just like this. Now Lull pulls up his stolen images of the inside of Aj’s skull.

“Your side of the deal.”

“All right. For me, this isn’t the mystery. This is the corroboration. The mystery is how she stopped those Awadhi robots. So when we rule out magic and we rule out God all we have left is technology. And that, in there, is technology; technology that could let a human brain communicate directly with a machine. She hacked them.”

“No God, no gods,” says Thomas Lull. Lisa feels a vibration run through the hull of the hydrofoil. The boat throttles back its waterjets, settling down on its foils on its approach to the crowded waters around Patna. Through the glass she makes out the cheap mass-built light industrial units and ex-urban infotech sprawl behind the Ganga’s wide, sandy reefs.