“The burn rate. The cost. The monetary cost of running the simulation. When a lot of neurons are engaged and a lot of signals are being passed over the connectome, the quantum processors at Hole in the Wall are busy, and so the system charges us more money, and draws it down from the account. I can log on and watch the balance in the account declining. Sometimes it declines fast, sometimes slow. If I draw a graph of the burn rate, it looks like this.” She peeled the top sheet off the pad to expose a new page and slashed out a long horizontal axis that presumably represented time. A shorter vertical axis was burn rate. Starting at their origin, she began to draw a line across the page, wiggling the pen randomly up and down. “At first, a lot of what looks like noise. Activity comes and goes in surges. I tried running some statistical packages against it but it’s pretty close to just chaos. But then later we start to see some periodicity emerge.” She began ticking the pen up, down, up, down, in a steady rhythm. “Like a heartbeat. Just for a little while. Then back to random.” More pen shaking. She was approaching the edge of the paper. “Just within the past week, though, it really settled down.” She slowed the pen’s progress and marked out a neat, regular series of ramps, each ramp ending with a sudden drop toward zero. The last of them went off the page. Having run out of paper, she flipped the pad around and held it up so that Enoch and C-plus could see her handiwork.

“And that’s where we are now,” she concluded. “As of an hour ago.”

“Like it’s stuck in some kind of repetitive cycle,” C-plus said. “That’s my takeaway from your graph.”

“That’s what worries me,” she said. “Or maybe it’s waking up, building to some level of activity, and then going to sleep again.”

“I would not recommend putting that kind of anthropomorphic language into your thesis,” Solly said.

“Of course.”

“A very basic question: can the connectome self-modify?” Enoch asked.

“Self-modification is a vast, separate thing from what I’m trying to do at this stage!” Sophia exclaimed. She glanced at Solly and C-plus and read in their faces that they were both as taken aback as she was by Enoch’s question. Oh, it was a fascinating topic to think about. But way out of scope for this project.

“‘Dear Mom,’” Enoch repeated.

“Okay. Okay. Mom, keep in mind there’s a huge difference between this simulation and a real brain. A real brain is a Heraclitean fire. Never the same brain twice. You can take a snapshot of the connectome at the moment of death—which is what we have done here in the case of DB—but that bears the same relationship to a real brain as a freeze-frame does to a movie. In a real brain, every single time a neuron fires, the brain rewires itself a little bit in response to that event. Frequently used connections get strengthened. Neglected ones atrophy. Neurons get repurposed. Things get remembered—or forgotten. And none of that is happening in my simulation.”