Pi Versus Information Theory

The mathematical constant pi is packed with meanings—or it’s meaningless

3 min read
Pi Versus Information Theory
Illustration: Jesse Lefkowitz

Many years ago, while having dinner with an eminent mathematician, I mentioned a scene regarding the number pi in Carl Sagan’s novel, Contact. A scientist from Earth (Jodie Foster in the movie) visits a distant planet and learns that the aliens there have calculated pi out to many places. Very far out in the number’s expansion the decimal digits turn to a very long string of ones and zeros—a message embedded in pi.

“How can you hide a message inside pi?” asks Foster’s character. “It’s built into the fabric of the universe. And what does the message say?”

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Asad Madni and the Life-Saving Sensor

His pivot from defense helped a tiny tuning-fork prevent SUV rollovers and plane crashes

11 min read
Asad Madni and the Life-Saving Sensor

In 1992, Asad M. Madni sat at the helm of BEI Sensors and Controls, overseeing a product line that included a variety of sensor and inertial-navigation devices, but its customers were less varied—mainly, the aerospace and defense electronics industries.

And he had a problem.

The Cold War had ended, crashing the U.S. defense industry. And business wasn’t going to come back anytime soon. BEI needed to identify and capture new customers—and quickly.

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