Link between quantum physics and game theory found

Jul 12, 2013

(Phys.org) —A deep link between two seemingly unconnected areas of modern science has been discovered by researchers from the Universities of Bristol and Geneva.

While research tends to become very specialized and entire communities of scientists can work on specific topics with only a little overlap between them, physicist Dr Nicolas Brunner and mathematician Professor Noah Linden worked together to uncover a deep and unexpected connection between their two fields of expertise: and .

Dr Brunner said: "Once in a while, connections are established between topics which seem, on the face of it, to have nothing in common. Such new links have potential to trigger significant progress and open entirely new avenues for research."

Game theory—which is used today in a wide range of areas such as economics, social sciences, biology and philosophy—gives a for describing a situation of conflict or cooperation between intelligent rational players. The central goal is to predict the outcome of the process. In the early 1950s, John Nash showed that the strategies adopted by the players form an equilibrium point (so-called Nash equilibrium) for which none of the players has any incentive to change strategy.

Quantum mechanics, the theory describing the physics of small objects such as particles and atoms, predicts a vast range of astonishing and often strikingly counter-intuitive phenomena, such as quantum nonlocality. In the 1960s, John Stewart Bell demonstrated that the predictions of are incompatible with the principle of locality, that is, the fact that an object can be influenced directly only by its immediate surroundings and not by distant events. In particular, when remote observers perform measurements on a pair of entangled quantum particles, such as photons, the results of these measurements are highly correlated. In fact, these correlations are so strong that they cannot be explained by any physical theory respecting the principle of locality. Hence quantum mechanics is a nonlocal theory, and the fact that Nature is nonlocal has been confirmed in numerous experiments.

In a paper published in Nature Communications, Dr Brunner and Professor Linden showed that the two above subjects are in fact deeply connected with the same concepts appearing in both fields. For instance, the physical notion of locality appears naturally in games where players adopt a classical strategy. In fact the principle of locality sets a fundamental limit to the performance achievable by classical players (that is, bound by the rules of classical physics).

Next, by bringing quantum mechanics into the game, the researchers showed that players who can use quantum resources, such as entangled , can outperform classical players. That is, quantum players achieve better performance than any classical player ever could.

Dr Brunner said: "Such an advantage could, for instance, be useful in auctions which are well described by the type of games that we considered. Therefore, our work not only opens a bridge between two remote scientific communities, but also opens novel possible applications for quantum technologies."

Explore further: Scientists find way to maintain quantum entanglement in amplified signals

More information: Paper: 'Connection between Bell nonlocality and Bayesian game theory' by Nicolas Brunner and Noah Linden in Nature Communications. www.nature.com/ncomms/2013/130… full/ncomms3057.html

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Tektrix
1 / 5 (5) Jul 12, 2013
Non-local Bayes- entangled priors . . . yeah, I can see that having some interesting advantages- correlated game states, for instance.
clay_ferguson
2.6 / 5 (16) Jul 12, 2013
This article is totally void of any actual information. Nothing but fluff. Do they mean if I can affect something on the other side of a wall, I have a better chance of winning a game? Is that the concept. They aren't even clear on that. Which aspect of Game theory are they referring to??? Not one single important detail is in this article.
hemitite
2.6 / 5 (5) Jul 12, 2013
So is what's behind door #2 could entangled with the contents of the envelope?
antialias_physorg
1 / 5 (2) Jul 12, 2013
Do they mean if I can affect something on the other side of a wall, I have a better chance of winning a game?

They mean that by not being confined to locality (e.g. via entangled entities) the individual agent can react to information from a larger region, and thereby make a more informed (read: better) choice.
vacuum-mechanics
1 / 5 (14) Jul 12, 2013
Quantum mechanics, the theory describing the physics of small objects such as particles and atoms, predicts a vast range of astonishing and often strikingly counter-intuitive phenomena, such as quantum nonlocality.


Okay, but quantum mechanics is still being 'physics' it is not a magic!

In the 1960s, John Stewart Bell demonstrated that the predictions of quantum mechanics are incompatible with the principle of locality, that is, the fact that an object can be influenced directly only by its immediate surroundings and not by distant events.


This seems like a magic, anyway even in the real world of magic there is 'physics' behind! Maybe there is a misinterpretation. Here is an interpretation based on 'physics' which is understandable…
http://www.vacuum...17〈=en
antialias_physorg
5 / 5 (1) Jul 12, 2013
This seems like a magic

Just because you don't understand it doesn't make it 'magic'.

To quote Arthur C. Clarke:
Any sufficiently advanced technology is indistinguishable from magic.


And QM seems to be sufficiently out of your league.

Science does not have to conform to what you think is 'common sense'. Common sense is something that developed through evolution based on observations of macroscopic environments. QM deals with microscopic environments.
Hence, why would you even expect your 'common sense' to map to that to any great degree?
Shoehorning observable/measurable facts into a 'vaccuum mechanics theory' that doesn't explain them and is internally inconsistent doesn't help.
dan42day
1 / 5 (9) Jul 12, 2013
In other news, the Euro-Millions lottery produced two winning tickets today, one sold in Bristol, U.K and the other in Geneva Switzerland. So far no one has stepped forward to claim their share of the prize.
visionabler
1 / 5 (1) Jul 13, 2013
This article is totally void of any actual information.


Obviously, any applications of quantum theory to game theory that were discovered by researchers are real game changers, and giving them away for free might not make sense. (Two puns included).
Urgelt
5 / 5 (3) Jul 13, 2013
I'm with Clay. The article doesn't make the case advertised in the lede. It fails to make it clear how quantum physics applies to game theory, and it makes no case at all for the reverse, game theory applying to quantum physics - which you'd expect if the disciplines were 'linked.'

If this is just about showing a gaming advantage of non-locality - possessing better information than those who are relying on merely local information - I don't see what the fuss is about.
dedereu
1 / 5 (9) Jul 13, 2013
Quite evident basically, for example, in chess playing, exploring in parallel coherently, at the same time, all the many parrallel microworld of quantum mechanics corresponding to all tjhe possible future moves, gives a formidable advantage over classical mechanic, exploring only one possibility at one time, so that it is nearly impossible to explore up to the end of the party, all the possibility, that quantum mechanis is able to explore in this one time !!
Our real world with quantummechanics is quite more powerful than the classical world that seems valid at the macroscopic level, with only one world amount the many parallel separated world appearing at each micro time, which is the only way to explain, without adhoc unproven hypothesis, why at the microscopic level it is possible to be delocalized at many place at the same moment and after decoherence at the macroscopic level, this possibility disappears, being at only one place and not working and on holiday at the same time.
ValeriaT
1 / 5 (10) Jul 13, 2013
This article is totally void of any actual information. Nothing but fluff. Do they mean if I can affect something on the other side of a wall, I have a better chance of winning a game? Is that the concept.
This article was written with person, who probably doesn't understand the stuff well. The quantum mechanics can be described with Bayesan probabilities, which don't involve no just atemporal observable states, but the states observable in the past or future too. The Nash equilibrium is one of applications of quantum bayesianism.
ValeriaT
1 / 5 (9) Jul 13, 2013
For example let's say a red and a black dice are thrown and there are two gamblers. Due to a brief slip by the croupier, one gambler knows that one of the dice is a six (but not which one) and the dice are fair, the other simply knows the dice are fair. The probability that the red dice was a six for the first gambler is 6/11, but for the second gambler the probability is 1/6.

QB similarly says that the probabilities as to the outcome of the same experiment may not be the same for two different observers, as for example one observer may've conducted a previous experiment which alters their knowledge of the system. As each probability distribution is associated with a quantum state, this makes the quantum state subjective too. It may seem like solipsism, but a proponent of QB would argue that quantum theory is an observer centric - which from a subjectivist Bayesian POV could be interpreted as the strength of belief of the observer.
kochevnik
1.4 / 5 (9) Jul 13, 2013
To me this seems an application of game theory to a particular problem. Declaring it tantamount to unifying the forces of nature or E=mc^2 is pure puffery
julianpenrod
1 / 5 (9) Jul 13, 2013
Among other things, "game theory" is just a scam. A collection of terms and phrases and concepts, but, in the end, the "winning strategy" is always given as ignoring what the mathematics say and choosing at random. "Economic" "expert" after "economics" "expert" get "Nobel Prizes" for applying "game theory" to "economics" to "explain" a situation, but not one of them ever succeeded in predicting anything like the U.S. economy crashing after 2007! It can be said that that's because "game theory" is like epicycles, it can be twisted and fit to conform to what happened, but predictions are never accurate! And note how they say Brunner and Linden "worked together to uncover a deep connection". How did they know it was there? It can't have been obvious if they had to "work at it". If it wasn't obviously there, how did they know what path to take? In fact, they just labored to concoct a misinterpretation of the situation that invalidly incorporates ideas from both.
ValeriaT
1 / 5 (8) Jul 13, 2013
not one of them ever succeeded in predicting anything like the U.S. economy crashing after 2007
You're right, but IMO it's not failure of theory. Every influential economist knows, that the stock market is in state of metastable equilibrium and that the fear mongering is the best way, how to introduce the panic at stock markets and the actual crisis. So that their primary rule is to keep denying the actual situation. Especially when every influential economist is practicing the stock markets too.
Shah Khan
1 / 5 (3) Jul 15, 2013
The title of this story suggests that the work of these authors is a ground breaking first. This is not the case. Links between game theory and quantum mechanics were first explored back in 1999-2000 by David Meyer and Jens Eisert et al, and since then have been further developed under the name of quantum game theory. It is always unfortunate when sensationalism triumphs over factual accuracy in science news.
jon cloke
1 / 5 (4) Jul 15, 2013
I'm horrified beyond words that you appear to think that Game Theory is actually science! It is "the study of mathematical models of conflict and cooperation between intelligent rational decision-makers"; in other words, it is an empirically unproven theory based on debatable pre-suppositions made by mathematicians about what constitutes 'intelligent' and 'rational' in human behaviour that have absolutely nothing to do with real human behaviour.

Game Theory works mathematically because it is pre-designed to do so in the mistaken assumptions it makes, rather than because it establishes any fundamental characteristics of human behaviour. It is beloved of orthodox economist for the same reason, that it permits post hoc rationalizations of capitalism, i.e. capitalism exists therefore let us assume that it is both logical and functional (through equilibrium-based modelling, rational preference assumptions, etc.).

Odd to see a physics blog making this kind of fundamental mistake!
Higgsbengaliboson
1 / 5 (6) Jul 15, 2013
Oh what an awesome connection.I took the course in artificial intelligence during my Engineering and I came in contact with game theory.John Nash ,"The beautiful mind" developed this field and now find it's connection with quantum Physics...both are skinny,intellectual field but game theory is more creative than probabilistic nature of Quantum Physics.

Those who are good chess player might understand that game theory gives the same pleasure as playing a game of chess against powerful computer.

But quantum theory...In world's of Feynman "bizarre".
JSCC
not rated yet Jul 24, 2013
it permits ... rationalizations of capitalism


Methinks this is your problem with game theory [excepting obvious inexperience], and that it has nothing to do with 'an empirically unproven theory based on debatable pre-suppositions made by mathematicians'. If that was the case, it wouldn't be capable of mathematizing natural selection. It is and has. This can then be translated into non-evolutionary game theory notation and provide equivalent results involving "conflict and cooperation between intelligent rational decision-makers".

So please drop the human behavior anti-intellectualism and be honest: you just don't like the possible implications, which is entirely unscientific because that's different than the method itself.