Science is one step closer to proving ‘quantum pseudopathology’ (and Spain has done its part)

Quantum entanglement is one of the most curious phenomena in nature. As we’ve heard many times (every time someone points to Schrödinger’s famous cat) particles can exist in two states at the same time. As soon as we notice them, these particles begin to “collapse” or bend, that is, they decide one state or another. Quantum entanglement occurs when two particles are linked in such a way that the “collapsed” state of one gives us information about the state of the other.

pseudopathology.
Schrödinger’s thought experiment is working to give us an idea at the macroscopic level of this quantum phenomenon, but it still thought experiment. Quantum game theory, for its part, proposes cooperative games, similar to John Nash’s famous prisoner’s dilemma, as a way to show that entangled particles can cooperate. The goal of this game is to demonstrate pseudo-quantum telepathy, the phenomenon by which these entangled (hence “pseudo”) particles appear to communicate and agree on strategies.

A team of researchers in China used one of these quantum games in an attempt to prove this quantum false telepathy and the results, Published in the magazine physical review messagesthey are positive.

The magic square.
The experiment is based on a proposal made by the Spanish physicist Adán Cabello, which in turn is based on the game designed by David Mermin and Asher Peres, from which it derives its name (Mermin-Peres). The game dynamics are simple: Alice and Bob (the names are file reference To another research on this topic) You must fill in the nine squares (3 x 3) with one of two values, 1 or -1.

Alice must fill her box so that the result is always 1, multiplied by the cells of her rows (i.e. 1,1,1 is a valid option plus -1,1-1 and variations of this last group). Bob must fill in his square taking into account his columns, the result of multiplying squares in the columns should always be -1 (ie -1, -1, -1 or 1, -1, 1 and similar combinations).

Rule It will take a row and a column of player chests. Bob and Alice win the game if, without calling each other, they fill in the common square in Alice’s row and Bob’s column with the same number.

Win the game.
If Alice and Bob were humans, they could design a strategy that would lead them to win eight games out of nine, and be able to build nearly identical squares, but they should always be different on at least one square. This is where Jia-Min Xu and colleagues’ work comes into play: Using pseudo-quantum telepathy Alice and Bob can exceed your expectations. Almost as if they were communicating in real telepathy.

The key in the principle is derived from the quantum: Nothing to be noticed. The squares that Alice and Bob fill in only appear when they are evaluated by the judge, and the values ​​that appear in the row and column are linked. There aren’t even Alice and Bob chests left, because they’ve gone unnoticed.

A step towards quantum computing.
This experience can open doors for Quantitative Statistics. For Anne Broadbent, of the University of Ottawa (who was not part of the team that conducted the study), for example, this experiment can be used to create software that allows checking the correct functioning of quantum computer.

For his part, Xi-Lin Wang stressed that the work would serve to “demonstrate the potential of our team’s favorite technology: entangled photons in polarization and angular momentum”. Part of the team’s success was based on creating a double bond for the same pair of photons (instead of making a simple bond for two pairs of photons).

Without a lens that tells us the future.
Putting such experiments into practice is not an easy task, Capello admitted himself. Quantum computing and related technologies such as Quantum cipher It makes headlines thanks to the speed with which new discoveries are being produced. Anyway, as usual, only time will tell The speed and direction they take us These are promising technologies.

picture | IBMAnd the CC BY-ND 2.0.1 Update