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Diaconis and magic in the shuffling of cards

Diaconis y la magia en el barajeo de cartas Diaconis and magic in the shuffling of cards

Diaconis and magic in the shuffling of cards. This incredible feat is associated with Persi Diaconis, an American mathematician who was able to guess ten consecutive cards in an electronic deck. A gang of casino users recorded shuffling of cards in a casino and managed to hack it. The losses were in the millions and those responsible for the casino decided to go to Diaconis and her partner Susan Holmes to solve it.

In Spain, the patriarch and thinking head of the Pelayos clan discovered that no machine is perfect. The Madrid family realized that casino roulette wheels had imperfections that made it possible to know which numbers were more likely to come out than others. A fact that shocked the industry. Although he has not been the only one.

Diaconis and magic in the shuffling of cards

You have to be in the United States. A gang of regular casino users discovered a fatal flaw in the machine that randomly shuffled the cards on a table. This fact allowed them to know in advance which cards had the best chance of coming out. And it is that the failure of this machine allowed to double or triple the advantage to know the next card. It is not legal to count the cards, but they did it and caused the businessmen enormous harm.

There were two victims, the casino itself and the company in charge of manufacturing the machine for shuffling cards. The casino went virtually bankrupt. And it is that the feat of this group of players allowed them to unseat the bank itself. And on the other hand, the machine company was questioned, since their machines were not perfect and anyone could expose them. If some players had achieved it, others could also achieve it.

Magic and statistics united to solve a mystery

Diaconis and magic in the shuffling of cards. Finally the company decided to contact Persi Diaconis to solve the mystery and that is that the company sold its machines to casinos in Las Vegas and other casinos around the world. In addition, said company was listed on the New York Stock Exchange. The catastrophe was huge and it is that the hacking into one of their machines led to millions in losses and endless headaches for a while.

The solution was to call the American Persi Diaconis. A mathematical genius who had the invaluable help of a colleague, Susan Holmes, a statesman also from Stanford University. They had in their hands to solve one of the most important mysteries that happened in Las Vegas.

The error of this shuffling machine made it possible to know the next card. A fact that multiplied by two or three the advantage to know which card could come next. This fact went unnoticed by ordinary mortals, but not by any good card counter.

Recordings: million-dollar gains and losses

How did they manage to discover the failure of the machine and discover that they could know the next number? With a video camera. Yes, something as simple as recording the shuffling of cards and carefully analyzing it afterwards.

A plan thinking to the millimeter that allowed this gang to win significant sums of money and the casino to lose them. According to what they say, they made a recording inside the casino itself that they could see from outside in a van. There some experts analyzed the way of shuffling and discovered the error. Once discovered, they had to put their theory into practice and find out if it really worked.

And of course it worked. The casino lost millions of dollars until it discovered what was happening. These types of actions put any company in check and the money lost does not return.

Launch of the new machine

Some time later the company released an impassable shuffling machine. The managers of the companies were aware that they needed to create a machine inaccessible to third parties and, above all, to recover the lost prestige. The first thing they did was to seal the machine so that no intruder could see how it was shuffling and could not hack it. And they also improved the randomness of the shuffle.

Was the new machine perfect? Diaconis and the magic in the shuffling of cards had it in their hands to test the new prototype before anyone else. Although again Persi Diaconis did not investigate alone, but she did it with her university classmate Susan Holmes.


Checkmate. That was the result of the research of these two geniuses. Diaconis and Holmes discovered a flaw in the mechanical action of the new prototype card shuffling machine.

The problem was in the ascending and descending sequences. What did it mean? That the machine was still imperfect and that it was possible to make predictions and determine the order of the cards.

Those responsible could not believe it and put their hands to their heads. His imperfect machine allowed errors and to determine the order of the cards. And that could only mean one thing, millions in losses again.

The couple of American mathematicians demonstrated to those responsible that they could guess a total of nine or ten cards in a row. This made it possible to multiply by two or three the possibilities of counting by a professional accountant. A dramatic fact that they did not want to believe. Finally they withdrew the machine and drew a thick veil (as they say.)

Who is Persi Diaconis?

A genius of mathematics, magic and cards. He possibly he is the genius of randomness of all time. Diaconis and the magic in the shuffling of cards, an explosive combination, which he continues to surprise years later. He manages to simplify any problem through the shuffling of cards.

It all started when he was a preteen at Tannen’s Magic Emporium in Times Square (New York). There he met Alex Elmsley, a Scottish magician and scientist, who is known for mastering the perfect shuffle.

For his part, Diaconis (1945) is capable of dividing a deck into two equal parts and inserting them by placing a card from each hand in less than ten seconds. Although it may seem like a simple fact, it is not, and few people are capable of achieving it. Obviously, Diaconis is one of them. This type of shuffling is not random, although it may appear to be. If done eight times in a row the deck is restored and returns to its original form.

From there, Diaconis’ life is history. History of magic and illusions.

Card counting

Card counting is something that has been around forever. There are expert card counters who, thanks to this ability, are able to predict the card that happens next. They start with an advantage that ordinary mortals do not. Currently this practice is illegal and in the event that a player is discovered doing so, they are immediately expelled and not allowed to play again.

An example is that of the American actor Ben Affleck who was discovered counting cards playing blackjack and was immediately expelled from the casino. The use of technology in the count is also not allowed.

Eva Arroyo

Author: Eva A. T.

Degree in journalism. Expert in casinos and sports betting for almost a decade.

I explore the world of games of chance with a critical and analytical look. I reveal the untold enigmas of the game. Each game is a new opportunity.