### Israel Gelfand, Sept. 2nd 1913 – Oct. 5th 2009

#### Posted by John Baez

Israel Gelfand died yesterday, at the age of 96.

He played a preeminent role in Russian mathematics for many years. His legendary seminar in Moscow ran for 50 years, and set the pattern for many others, including Sullivan’s seminar at CUNY and Drinfeld’s at Chicago. His name is attached to many mathematical achievements, including:

- the Gelfand representation of a Banach algebra,
- an important special case, the Gelfand–Naimark theorem describing commutative C*-algebras,
- the Gelfand–Naimark–Segal construction describing general C*-algebras,
- the Gelfand–Fuks cohomology of a foliation,
- the Gelfand–Kirillov dimension of an associative algebra,
- the Bernstein–Gelfand–Gelfand resolution for representations of simple Lie groups.

But this are just the tip of the iceberg! For example, seeing these you might never guess that he helped write a 5-volume work on distribution theory.

Here’s a bit more about Israel Gelfand, taken from a New York Times article written by Marilyn Kochman in 2003:

On the eve of his 90th birthday, Israel M. Gelfand reflected on the essence of mathematical achievement. ”It is not only about aptitude,” he said, sitting in his cozy office on the Busch campus of Rutgers University in Piscataway. ”It is about appetite.”

Dr. Gelfand, a distinguished visiting professor of mathematics at Rutgers, and widely considered to be among the greatest mathematicians of the 20th century, has demonstrated a voracious appetite for mathematics and more.

For more than 70 years, he has conducted pioneering research in every branch of mathematics, collaborated with colleagues around the world, guided the doctoral theses of countless students, and established correspondence schools in the Soviet Union and in the United States.

In addition, he founded a mathematics seminar at Moscow State University that met weekly for nearly 50 years and has become a legend among mathematicians.

”Gelfand bridges mathematics in the first half of the 20th century with the 21st century,” said Prof. Alexandre Borovik, who teaches mathematics at the University of Manchester Institute of Science and Technology in England. ”Most mathematicians define themselves according to their specialty, for example, a topologist, an algebraist, or a number theorist. But Gelfand has the ability to understand and to speak almost every mathematical language–and there are nearly as many of those as there are human languages.”

Dr. Gelfand, who lives in Highland Park, has made an indelible impact in such areas as functional analysis, representation theory, geometry and integrable systems.

His studies on Banach algebras and infinite-dimensional representations of Lie groups have become standard fare in advanced textbooks, and essential background for further advances in the fields.

Dr. Gelfand, who is 5 feet 6 and has piercing blue eyes, continues to work at an astonishing pace. In the past several years, he has written more than a dozen papers, two scientific texts, and two high school texts.

”I think I am able to work as well as I could 40 or 50 years ago,” said Dr. Gelfand, who attributes this productivity, in part, to a strict vegetarian diet, which he adopted, along with his wife Tatiana, a decade ago.

Dr. Gelfand’s achievements and published work extend beyond mathematics.

In 1958, when he was 45, he became interested in cell biology and neurophysiology. Dr. Gelfand’s entire body of published work encompasses more than 600 papers and books.

”Hiring Gelfand in 1990 was my greatest accomplishment,” said Prof. Felix Browder, who teaches mathematics at Rutgers. He championed Dr. Gelfand’s appointment when he was the vice president of research for Rutgers. (Professor Browder is also a noted mathematician whom President Clinton named a 1999 recipient of the National Medal of Science, the nation’s highest science and engineering honor.)

By the late 1980’s, the Soviet government relaxed its restrictions on emigration, and Dr. Gelfand, along with myriad others, was able to leave the country. His children also live in the United States: Sergei, a mathematician; Vladimir, a biologist; and Tatiana, a student of psychology and art.

And here’s a bit about his seminar in Moscow, from the same article:

In 1943, Dr. Gelfand established the legendary Mathematics Seminar, which operated independently of the university and was open to everyone. It would produce several generations of talented mathematicians.

”The seminar, held each Monday night on the 14th floor of the grand Moscow University building, was a remarkable and unique phenomenon,” said Prof. Edward Frenkel, who teaches mathematics at the University of California at Berkeley.

He attended Dr. Gelfand’s seminar while a graduate student in Moscow.

”Each week, about 100 mathematicians would attend,” Professor Frenkel said. ”The seminar started at seven and people often stayed until after midnight, without a break. They came to hear what Gelfand had to say. He was sort of an oracle who had a keen ear for the beauty of mathematics. He could see its most interesting and promising directions, and help you feel the unity of mathematics.”

If Dr. Gelfand sensed that seminar participants were not following the presentation, he would intervene.

”As soon as a topic became fashionable, I changed it,” Dr. Gelfand said, explaining that he did not want the students to blindly follow him and his ideas.

”It was during the era of totalitarianism,” he said. ”I hated leadership and didn’t want to be a leader, myself.”

## Re: Israel Gelfand, Sept. 2nd 1913 – Oct. 5th 2009

Here are some remarks that Todd Trimble posted on another thread: