Quantum Mechanical Con Game

May 05, 2008

For the first time, physicists have come up with a scheme that would allow a quantum mechanical expert to win every time in a con game with a victim who only knows about classical physics. Prior quantum cons have typically been vulnerable to simple countermeasures.

A pair of physicists at Tel-Aviv University in Israel came up with the quantum cheat by imagining two people betting on the location of a particle hidden among a set of boxes. In the game, a quantum mechanical con artist named Alice turns away as her classical victim, Bob, is allowed to look inside one of two boxes sitting on a table to see if there is a particle inside. He then closes the box and Alice guesses whether or not Bob found anything in the box he chose. If she guesses correctly, she wins Bob's money, if not, she pays him.

Classically, there is a 50% chance of Alice getting it right. If instead she's adept at quantum mechanics, and has a third box hidden away, she can ensure that she always knows what Bob found in his box. All she has to do is prepare the particle in a state that essentially places it in all three boxes simultaneously, through a phenomenon known as quantum superposition. In effect, there is an equal chance of the particle turning up in any one of the boxes.

After Bob looks in one of the two boxes on the table, Alice measures the state of the particle in her hidden box. If she finds it empty, she knows Bob saw the particle in the box he opened. If she finds that the particle is in a superposition between two boxes, she knows that Bob opened the third box but didn't see anything inside. In either case, she always knows what Bob found, even though she has no way of knowing in advance where the particle will turn up or which box Bob chose to look in.

The authors of the paper admit that the current state of technology isn't good enough for a con artist to make money with quantum mechanics. But they believe that this is the first time anyone has shown that it's theoretically possible for someone like Alice to use quantum mechanics to win every time in a game that classical physics would only give her a fifty-fifty chance of winning. 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.

Citation: N. Aharon and L. Vaidman, Physical Review A (forthcoming)

Source: American Physical Society

Explore further: Could 'Jedi Putter' be the force golfers need?

add to favorites email to friend print save as pdf

Related Stories

Making quantum encryption practical

May 21, 2013

One of the many promising applications of quantum mechanics in the information sciences is quantum key distribution (QKD), in which the counterintuitive behavior of quantum particles guarantees that no one can eavesdrop on ...

Secure communication technology can conquer lack of trust

Jan 02, 2013

Many scenarios in business and communication require that two parties share information without either being sure if they can trust the other. Examples include secure auctions and identification at ATM machines. Exploiting ...

Quantum causal relations: A causes B causes A

Oct 02, 2012

A deeply rooted concept in everyday life is causality; the idea that events in the present are caused by events in the past and, in turn, act as causes for what happens in the future. Physicists from the ...

Recommended for you

Could 'Jedi Putter' be the force golfers need?

6 hours ago

Putting is arguably the most important skill in golf; in fact, it's been described as a game within a game. Now a team of Rice engineering students has devised a training putter that offers golfers audio, ...

Better thermal-imaging lens from waste sulfur

21 hours ago

Sulfur left over from refining fossil fuels can be transformed into cheap, lightweight, plastic lenses for infrared devices, including night-vision goggles, a University of Arizona-led international team ...

User comments : 2

Adjust slider to filter visible comments by rank

Display comments: newest first

thales
not rated yet May 05, 2008
See, quantum physicists are unethical.
nilbud
1 / 5 (1) May 05, 2008
Is this really the level of thought which these mooks are working at. They've gone from poisoning cats to embezzling money from morons.

More news stories

Could 'Jedi Putter' be the force golfers need?

Putting is arguably the most important skill in golf; in fact, it's been described as a game within a game. Now a team of Rice engineering students has devised a training putter that offers golfers audio, ...

LinkedIn membership hits 300 million

The career-focused social network LinkedIn announced Friday it has 300 million members, with more than half the total outside the United States.

Magnitude-7.2 earthquake shakes Mexican capital

A powerful magnitude-7.2 earthquake shook central and southern Mexico on Friday, sending panicked people into the streets. Some walls cracked and fell, but there were no reports of major damage or casualties.

Sun emits a mid-level solar flare

The sun emitted a mid-level solar flare, peaking at 9:03 a.m. EDT on April 18, 2014, and NASA's Solar Dynamics Observatory captured images of the event. Solar flares are powerful bursts of radiation. Harmful ...