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Oh the games twins can play.

When Israeli computer prodigies Alexander and Michael Bronstein found out that only Alexander had been accepted to an honors program at Haifa’s Technion Institute, they quickly hatched a plan.

A plan that allowed them to both attend.

“My brother and I decided to do what is, technically speaking, ‘time sharing,'” said Michael with a sly giggle.

“He’d go to half the lectures and I’d go to half the lectures. This lasted about four years, and only when we graduated did we decide to admit what we’d done to the head of the program.

“Luckily, he was not angry.”

While school officials or most anyone else can’t tell the tall, rail-thin and bearded 23-year-old brothers apart, future mischievous twins may not be able to pull the same scam — thanks to the Bronstein brothers themselves.

The twins have developed facial recognition technology exact enough to discern Alexander from Michael. In addition to curtailing the Russian-born Bronsteins’ shenanigans, the twins’ device may one day keep terrorists off airplanes or even replace ATM cards.

Michael, who spent the summer in Silicon Valley toiling at a high-tech company via a Technion internship program, explained the ins and outs of facial recognition at a recent American Technion Society event in San Francisco.

Though initially shy to speak with j. about his work (his grandmother once angrily called him after watching a news report that he and his brother were working on a weapon designed to blind enemy soldiers) Michael went on to explain — in basic terms — how his device works.

The brothers’ invention began with a challenge from their electrical engineering professor, Ron Kimmel. He promised them an A in his class if they could develop a facial recognition scanner fine enough to tell them apart.

Guess what grade the Bronsteins got?

Starting with the algorithms of Kimmel and a former student, Asi Elad, the brothers constructed a 3-D scanner that allowed them to bypass many of the pitfalls of two-dimensional facial recognition — which can often be foiled by simply having a bad hair day and not looking like your photo. As impressive as the scanner was, however, the sum was more than the parts: Legos and a laser pointer.

A more-advanced “second-generation” scanner was built in a marathon, two-day session prior to a Jerusalem science fair. Michael admits his brother did most of the actual assembling, but joked that the value of his loud and frequent exhortations to “Come on, already!” and “Do it!” cannot be undervalued. In a step up, the second-generation scanner was constructed mostly out of household electronics.

Finally, cooperating with laboratory engineer Eyal Gordon, the Bronstein twins constructed their current, “third-generation” scanner, which can scan an entire face in less than a second with a depth resolution of 1 millimeter.

But once a face has been scanned, how can you tell it from another? The process is exceedingly difficult, and draws largely upon the works of John Nash, perhaps America’s best-known mathematician after the runaway success of “A Beautiful Mind.”

But, skipping all the complex mathematics, during the fraction of a second that one’s visage is scanned, the distance between thousands of different points on the face is measured. Even if one contorts his or her face into a strange expression, the distance between these points remains the same.

So far, according to Michael, the device has been tested with several hundred faces and has a success ratio of greater than 99 percent.

While Michael is optimistic about the future of his facial recognition technology — the brothers and Kimmel have applied for a joint patent — he’s not sure how soon it will be able to deal with “some bad guy in the airport” intentionally trying to outfox it.

“Basically, facial recognition can be divided into two classes: one to many or one to one,” he explained.

Airport security, the attempt to find one villain among a crowd of many, could be years away. Plastic surgery, aging or prosthetic devices could still throw off the scanner.

However, he’s more optimistic that the technology can be applied to office security situations or at the ATM machine—where most would want to be recognized—in a timely fashion.

The twins’ breakthrough has not gone unnoticed, as dozens of news sites in myriad languages have picked up the story. Michael has even found articles about himself in Chinese. Yet, as the Bronsteins’ grandmother can attest, the newfound fame is not always a benefit.

Sometimes, however, it can be. After undergoing their “time-sharing” arrangement for years, Michael was invited to deliver a speech before the very same lecture series he once could only attend illicitly.

And, as he readied himself to speak, the head of the program turned to the audience and introduced him — as Alexander Bronstein.