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Future Tense: Quantum Precog


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Quantum Precog, illustration

Credit: Alicia Kubista / Andrij Borys Associates

She mopped the beads of sweat from her brow. It was 3 A.M. but still 82 degrees in the interrogation room. Freakin' global warming. Her partner, Dan Minkowski, took over the questioning.

"Okay, Doctor Morris, you say the computer told you to kill your friend. Have you ever been diagnosed with schizophrenia?"

The accused slumped in his seat. He looked more like a singer in an 1980s punk band than a computer scientist. "No... look, I want to go back to the beginning."

She got in before Minkowski. This needed subtlety. "That's a good idea, Doctor Morris. Can I call you Piet?"

Morris nodded. "Fine, whatever. This would never have happened if Doug hadn't misused my prototype. He's... was a psychologist. Studying precognition."


"He'd used my computer to go online, to get the lottery results a week in advance."


Precognition. Working in Cambridge she'd got used to the odd preoccupations of Harvard and M.I.T. "Isn't that telling the future?"

"Kind of. Doug tested the ability of subjects to predict random events. The difficulty is assessing the statistical significance..."

"Okay, I get it," she interrupted. These academics couldn't resist lecturing.

"No, you need to know this. The experiments measure small deviations from randomness. Say you've got a computer program showing two closed curtains. It randomly chooses one or the other to open. The subjects guess ahead of time. Say they get a 52% hit rate. In the long run, that's significant. But it's easy to screw up the random stream."

"Stream?" Minkowski had his baffled face on.

"Stream of numbers," said Morris. "Give me a dozen random numbers between 1 and 10."

"You want...?"

"Humor him," she cut in, not wanting Morris to clam up. "Okay, Piet, um 1, 7, 2, 4, 9, 5, 8, 1, 10, 7, 3, 5?"

"That's terrible." Morris shook his head. "There were no sequential duplicates. And you're jumping around too much. A real random sequence would include some closer numbers."

She scratched her head. "But they use computers, right? And they can do random."

"Not really," said Morris. "They approximate with an algorithm. So Doug Hoffenmeyer checked his results to see if his subjects were just guessing. He had the idea of using my prototype quantum computer as the control. To be honest, he wanted to save money; he liked to keep his budget for his departmental outings with my wife."

She raised an eyebrow at Dan. "Quantum computer?" Wife?

Morris nodded. "It's my baby. There are hundreds of labs developing them, but mine's the first full prototype. A quantum computer uses quantum particles instead of binary bits to store information. It can work with infinitely long decimals. Transforms mathematical operations."

"Yeah, that's great, Piet," she said. "But why would it tell you to kill the guy?"

"This is where it gets messy. A week after he started using my numbers, Doug turned up complaining. Every value in the sequence was duplicated a week later in his tests. Naturally he thought somehow my computer was interfering with his. But we isolated them and still it happened. The numbers generated by the quantum computer predicted the values Doug's experiment produced a week later. Consistently. The damned computer was a precog."

A large drop of sweat had now formed on the tip of her nose. She swept it away, irritated. "You can't be serious? How?"

"We don't know for sure. Quantum theory suggests we live in a many-worlds universe, where all possible futures are played out. Maybe my quantum device was entangled with a future period. That would explain the fixed gap."

She spoke slowly. "But why the homicide?"

"Accident. I never intended to kill him. Doug was in my office talking about dropping his line of research, just concentrating on my computer. I had to leave him a couple of hours for a faculty meeting. When I got back he was in shock. He'd used my computer to go online, to get the lottery results a week in advance. So then he wanted his password for the lottery website, to buy his ticket and make millions. The password was stored on the university notes database. Only it wouldn't let him in. Because he no longer worked there. He was no longer alive. He was deceased... would be deceased. In three days time. The machine was showing his future."


He was no longer alive. He was deceased ... would be deceased. In three days time.


Minkowski shook his head. "So it said he would die. But why did you kill him, Doctor Morris?"

"We've heard the rumors." She watched him carefully. "Hoffenmeyer's affair with your wife. You killed him and thought you'd covered it up. Only we found out and now you've dreamed up this excuse."

"No," said Morris. "He was going to die anyway, but it was just an accident that I killed him. He ran out in front of my car. I couldn't stop in time."

Her head was thumping. Could it really be coincidental? Had the computer predicted the future or influenced it by prompting Morris to take revenge and pretend it was an accident? She stared at the still blank form in front of her. Her report could wait 'til morning.

Some things were better left in the future.

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Author

Brian Clegg was a senior manager in the IT department of British Airways and is now a popular science author. His most recent book on randomness and probability in life and the universe Dice World, Icon Books, London, has been featured in a variety of publications.


Copyright held by Author/Owner(s).

The Digital Library is published by the Association for Computing Machinery. Copyright © 2013 ACM, Inc.


 

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