Behind Dick Lipton’s ready smile, his brain is working, ever on the lookout for problems to tackle.
“I’ve always been willing to be a problem solver, even to solve everyday problems,” Lipton says. “I really appreciate the joy of discovering something that no one else has seen or discovered, or maybe even noticed. It’s one of the things I’m known for.”
Professor Richard J. “Dick” Lipton is known for many things: his work in complexity theory, program testing and software engineering, cryptography, and DNA computing—of which he is generally acknowledged to be a pioneer.
It is with good reason that he was elected to the National Academy of Engineering in 1999 and selected as both an ACM and a Guggenheim Fellow, and that the Association for Computing Machinery refers to Lipton’s work over the last 30 years as “the most influential work in the field.”
But not only does Lipton come up with solutions to hard problems, he also explains them in a way that even non-computer-scientists can understand. With the ease of a good storyteller, Lipton can make a groundbreaking theory about planar separators sound downright obvious.
It’s a talent that has not been lost on his students. Lipton tells a story about one semester at Princeton, where he was teaching an introductory computer science class. It was standing room only on the first day, but he assumed many of the students were just shopping around and wouldn’t actually enroll. They would find it too “hard,” maybe. Too complicated.
“Some of the students came up to me right after class and said they hadn’t planned to sign up,” Lipton says. “But after they heard my first lecture, they realized they could actually take a computer science class.”
Lipton’s important contributions to computer science extend into many fields and many topics. He developed the planar separator theory with R. Tarjan that leads to elegant recursive algorithms for planar graphs, and he advanced complexity theory with his proof of the Karp-Lipton theorem while at Berkeley in 1980.
He has done prominent work in the field of cryptography, where he cracked “Mental Poker,” which led others to state precisely the notion of semantic security.
And along with Len Adleman, Lipton did seminal work in the field of DNA computing, a combination of molecular biology and computer science that shows that DNA molecules can be used to solve complex combinatorial problems.
This variety in his work gives him great satisfaction, he says, and the variety in his colleagues’ work at CoC is one of the best things about being here.
“I just get excited about working on such interesting problems. I love the people, and how broad we are,” he says. “I’ve taught computer science at other universities, and it’s not quite the same. We are a real College of Computing.”
Lipton taught at Yale, U.C. Berkeley and Princeton before joining the faculty at the Georgia Institute of Technology in 2000. He is currently associate dean of research, professor, and the Frederick G. Storey Chair in Computing at CoC.
In addition to his academic work, Lipton was founding director of a computer science research laboratory for the Panasonic Corporation and is now a chief consulting scientist at Telcordia (formerly known as Bellcore).
“Computers cannot do certain things, and there are problems that cannot be solved. Those are conjectures, the conventional wisdom. Of course, there’s a danger in these beliefs,” Lipton says. “One thing that would cause a big upheaval is if someone came along and showed that one of these conjectures is wrong. That would be a really big deal.”