Math students hear about secret codes at UC Davis

More than 500 teens and their parents packed into one of the largest lecture halls at UC Davis on Wednesday to hear Dr. David Perry, a U.S. Department of Defense cryptologist, decipher the world of encryption and break down the story of the notorious Enigma machine.

Perry’s lecture was the centerpiece of Math Fest 2009, an effort by the UC Davis mathematics department to get youths interested in the world of numbers. This year was the third annual Math Fest.

“We’re hoping to convey that mathematics is at once beautiful, powerful, fun and useful,” said math professor Monica Vazirani. “Getting a degree in math unlocks so many doors and prepares you for a wide variety of careers.”

The UC Davis effort to excite younger kids about math and science also encompasses the COSMOS (California State Summer School for Mathematics and Science) program. COSMOS is a four-week residential program for older students that allows them to focus on a topic such as chemistry, robotics, earth science or math.

Perry said cryptology and the study of ciphers dates back as far as Julius Caesar. Caesar used encryption to ensure secure communications with his troops on the front lines in Gaul.

Cryptology is a mainstay in modern militaries, but it’s now so common it touches most people today in the form of online commerce.

“It’s in software bundled up in your Internet browser,” Perry said.

When something is ordered from a Web site, computers encrypt credit card information so that even if it’s intercepted by a hacker, it’s extremely difficult to read the critical numbers.

Perry teaches a summer cryptology course for teens at the Center for Talented Youth program at Johns Hopkins University in Baltimore. He tries to engage students in math in a variety of ways.

“You absolutely have to mix up what you do – a little bit of lectures, working in groups, and activities,” Perry said.

One of the activities he coaches is building part of the Enigma machine out of card stock – which is then used to simulate encoding and decoding mechanisms that were used in the machine.

The Engima machine was a device used by the German military in World War II to communicate encrypted messages. The Germans thought the ciphers it produced would be unbreakable by the allies. They were wrong.

Perry’s course teaches students to understand not only the history of the Enigma machine, but also decisions that went into its design – the mathematical foundations – and more importantly, why the Germans thought it was so secure.