The sun went behind the ridge a little after seven and the temperature dropped 20 degrees in minutes. Vlad put on everything in his pack and sat with the tablet inside his jacket, working one-handed so the screen stayed covered.
Marcus ate, fiddled with the blister on his toe, and was asleep by seven thirty, flat on his back with his mouth open.
They had walked the last four hours in the shadow of the ridge with the solar panel strapped to the top of Marcus’s pack, facing the wrong way most of the time. Vlad had thirty-one percent in the battery and was paying too much attention to how much was left.
Samantha came over and sat down next to Vlad.
“Give me your hands.”
“They are fine.”
She took the left one and turned it over. Both heels were cut up from the scree and one of the cuts still had grit in it. She poured water over it and Vlad swore at her in Ukrainian.
“Say it in English.”
“No.”
“You do this at the office too. Somebody breaks the espresso machine and you go Slavic.”
“Marcus is asleep and cannot defend himself.”
She finished the other hand and let go of it.
“Where are you,” she said.
“Seventeen.” He brought the list up. “Two of them are the same company filed under different names. One has been down since March — they are stupid and publish their maintenance calendar. Three national labs. Four universities. Ten companies.”
“How many in the US.”
“Eleven of the seventeen.”
“Okay.”
“This one wanted you,” Vlad said.
“Kestrel.”
“Kestrel Atomics. Broomfield, Colorado. Six thousand atoms.”
“No.”
“I did not say anything.”
“You were going to.”
“I was going to say six thousand atoms.”
“It’s a good machine,” Samantha said. “It’s also a three hour drive from our lab. It’s too obvious.”
“Yes.”
“So we’re not talking about Kestrel.”
“We are not talking about Kestrel.” He moved it down the list anyway instead of off it. “But you told Marcus a few hundred. This says six thousand.”
“A few hundred logical. You spend the rest keeping those few hundred honest.”
“So six thousand is better.”
“Six thousand is longer. You can run a longer circuit before it comes apart.”
Vlad put the tablet down in the grass.
“I have a question and it is not about the list.”
“Okay.”
“I have been trying to work out who else can do what you did. I can’t figure it out. You run it ten thousand times and build the answer out of the pile. Where is the answer before you build it.”
“In the machine.”
“Where in the machine.”
Samantha paused. She looked down at her feet before answering.
“That’s a physics question.”
“You are the closest thing to a physicist anywhere close to here.”
“Nothing in there ever holds the answer,” she said. “Every run is a pile of wrong answers arranged so they cancel each other out. What doesn’t cancel is the right one.”
“That is not an answer to where.”
“No. It isn’t.”
“Deutsch asked it.”
“Deutsch asked a lot of things.”
“He asked where the factoring happened. Three hundred qubits hold more numbers at once than there are atoms in the universe.”
“That’s on a T-shirt.”
“It is also true. The work does not fit in the machine and the machine gives you the answer anyway. He said it happened somewhere.”
“Most people think that’s a bad question.”
“Do you?”
Samantha turned her head and looked at him.
“No.”
Vlad waited.
“Here’s the part that bothers me,” she said. “All I did was move a line. There’s a line between the work that has to happen in there and the work I can do out here on a laptop. People have been pushing on that line for ten years and it gives a little every year. I found out it goes much further than that.”
“A line that moves is a parameter.”
“Yes.”
“A parameter has a range.”
“That’s what I think about when I can’t sleep.”
“Say the range.”
“I can’t. I can tell you what having one means. People have argued for a hundred years about whether the other branches are real or whether they’re just how you write the arithmetic down. If they’re only arithmetic, I don’t see why the line should move that far.”
“And you moved it.”
“I can’t say they aren’t real. I used to say that in a seminar and nobody blinked.”
“Then what stops you,” Vlad said.
“Looking. The second you measure, everything that isn’t the answer is gone. You can arrange them and make them cancel in any pattern you can write down. One number comes out. Nothing else crosses.”
“How far are you from making something else cross.”
“I don’t know where to start.”
“That is not the same as far.”
“No,” Samantha said.
Vlad pulled his hands up into his sleeves.
“Is there one where I did not answer Marcus’s email?”
“If it’s real, there’s one where you didn’t.”
“What is he doing.”
“I don’t know. He never heard of any of us.”
Vlad wanted to know what that one was doing. He got up and checked the antenna, which did not need checking.
Marcus said, without opening his eyes, “Are you two talking about physics.”
“No,” Vlad said.
“Good.” He rolled onto his side.
Vlad sat back down and picked the tablet up out of the grass but did not turn it on.
“Sam.”
“Yeah.”
“I followed all of that.”
“You did.”
“You have never shown me the reduction. You have never said one line of it out loud where I could hear it.”
“No.”
“And I got there anyway.”
“You’ve been sitting six feet from it for two years.”
“Kestrel has not been sitting six feet from it.” He turned the tablet over in his hands. “When did you last publish anything.”
“Sixteen months ago. Seventeen.”
“What was in it.”
“The wrong version of the middle of it.”
“How wrong.”
“Wrong enough that it didn’t work.” She thought about it. “Right enough that I kept going.”
He should have waited until morning. He couldn’t wait, so he brought the link up.
The paper was where she had left it, with her name on it and the lab’s name under it. Underneath were the places where people repost things. He went through them and counted the copies that had gone up in the last four days.
Eleven.
He brought the link down and sat with the dead screen in his lap.
“There are eleven copies of your paper on the internet that were not there a week ago.”
Samantha did not say anything.
“Assume somebody good reads it now. They are not guessing whether it can be done. We did that part in front of them.” He put the tablet inside his jacket. “How long.”
“The math or the machine.”
“Math.”
She was quiet long enough that he thought she was not going to answer.
“Eight months. A year if they’re careful.” She pulled the bag tighter around her shoulders. “It’s a small paper with one thing taken out of it.”
“And the machine.”
“Two years. That’s what it took me.” She looked down at the water. “One person and one machine. Put sixty people on it with the same one machine and I don’t know what the number is.”
Vlad sat there shivering.
“Do not tell Marcus,” he said.
“Why.”
“Because in the morning he will want to do something.”
Samantha looked over at Marcus with his mouth open.
“He should,” she said. “You tell him.”