In their work, say the researchers, they have shown that the weird, quantum effects of entanglement could theoretically give blackjack players even more of an edge than " card counting " techniques where players at a table work as a team to keep track of and covertly communicate amongst each other the cards they have been dealt. With that knowledge, the players can then estimate the cards still in the deck, and those most likely to be dealt out next - all to help each player decide how to place their bets, and as a team, gain an advantage over the dealer.
The card counting strategy was made famous by the MIT Blackjack Team , a group of students from MIT, Harvard University, and Caltech, who for several decades starting in 1979, optimized card counting and other techniques to successfully beat casinos at blackjack around the world — a story that later inspired the book “Bringing Down the House.”
The edge achieved from card counting can be increased, say the researchers, in a theoretical scenario in which two players, playing cooperatively against the dealer, can better coordinate their strategies using a quantumly entangled pair of systems. Such systems exist now in the laboratory, although not currently in forms convenient for any practical use in casinos.
In their study, the researchers found that such quantum communication would give the players a slight advantage compared to classical card-counting strategies, though in limited situations where the number of cards left in the dealer's deck is low.
"It's pretty small in terms of the actual magnitude of the expected quantum advantage," says Joseph Lin, a former graduate student at MIT and first author of the paper on the study. "But if you imagine the players are extremely rich, and the deck is really low in number, so that every card counts, these small advantages can be big. The exciting result is that there's some