# At Last, Quantum Mechanics Makes it to the Back Alley

A gentle touch for better control, a quantum mechanical con, and milestone PRL papers

Gaming and gambling have inspired a number of advances in science and technology, going from Babbage’s fascination with horse racing through the invention of Unix to support a game of “Space Wars” to the upward climb in personal computing capabilities driven by video game performance. The article above finally shows that people are starting to think about exploiting quantum mechanics for the purpose of rigging games and winning bets off classically-thinking suckers.

The basic gist is that, in theory, particle-sharp Alice will fleece classic physics chump Bob by allowing him to examine one of two boxes. Bob’s task is to observe a particle in the box; he notes whether he does or does not detect a particle in the box he has selected. Alice’s pitch is that the particle is in one of the boxes, and that she will try to guess whether Bob did or did not observe the particle in his choice of box. Because Bob is thinking in terms of classical physics, he thinks it is a fair game; Alice should only be able to guess at chance levels, in this case with a fifty-fifty chance of being right. With many repeated plays, the number of wins for Alice and Bob should be about the same, or so Bob thinks. However, Alice isn’t about to let Bob leave with cash left in his wallet, and actually has three boxes. The particle at issue is set up before each round to have a quantum superposition such that it could be in any of the three boxes. Alice’s third box, though, has a detector in it, so if Alice checks after Bob attempts an observation, she either detects the particle, in which case she answers the Bob didn’t observe it in his look, or she doesn’t, in which case she answers that Bob did observe it, since Bob’s observation thus collapsed the superposition and means that there is nothing for Alice’s detector to detect anymore. Alice can win every time this way.

It’s good to know that quantum mechanics has finally made it out of the dull and boring role of providing the basis for modern electronics and stuff like LASERs, and now shows theoretical promise for displacing the three-card-Monty game in the back alley near you.

With advances in quantum technology, it may someday turn out that gambling is only risky for those of us who don’t understand quantum mechanics.

Part of the reason that gambling is risky has nothing to do with understanding the game at hand and everything to do with human cognitive wiring. Gambling tends to payoff on a variable schedule, and that happens to increase the frequency of the behavior via operant conditioning even more than fixed payoff schedules.

#### Wesley R. Elsberry

Falconer. Interdisciplinary researcher: biology and computer science. Data scientist in real estate and econometrics. Blogger. Speaker. Photographer. Husband. Christian. Activist.

### One thought on “At Last, Quantum Mechanics Makes it to the Back Alley”

• 2008/05/06 at 3:05 pm