Leon Lederman, explorer (and explainer) of the subatomic world, dies at 96

NEW YORK — Leon Lederman, whose ingenious experiments with particle accelerators deepened science’s understanding of the subatomic world, died early Wednesday in Rexburg, Idaho. He was 96.

His wife, Ellen Carr Lederman, confirmed the death, at a care facility. She and Dr. Lederman, who had long directed the Fermi National Accelerator Laboratory outside Chicago, had retired to eastern Idaho.

Early in his career Leon Lederman and two colleagues demonstrated that there are at least two kinds of particles called neutrinos (there are now known to be three), a discovery that was honored in 1988 with a Nobel Prize in physics. He went on to lead a team at the Fermi laboratory, in Batavia, Ill., that found the bottom quark, another fundamental constituent of matter.


For those baffled by such esoterica, Dr. Lederman was quick to sympathize.

“ ‘The Two Neutrinos’ sounds like an Italian dance team,” he remarked in his Nobel banquet speech. But he was determined to spread the word about the importance of the science he loved:

“How can we have our colleagues in chemistry, medicine, and especially in literature share with us, not the cleverness of our research, but the beauty of the intellectual edifice, of which our experiment is but one brick?”

He used his share of the prize money (physicists Jack Steinberger and Melvin Schwartz were also awarded the Nobel in 1988) to buy a log house in Idaho, in the Teton Valley, where he would later retire. By that time he was known as a preeminent figure in both discovering new physics and explaining it to the rest of the world.

“We’re teaching high school science in the wrong order — biology, chemistry, and then, for 20 percent of the students, eventually physics,” he told Claudia Dreifus in an interview with the Times in 1998.


“The subjects are unrelated, to be learned and forgotten — in the order taken,” Dr. Lederman lamented. Much better, he said, would be to begin with physics, including a basic understanding of atoms. That would lay the groundwork for chemistry, in which atoms join to form molecules, and then biology, where the interaction of molecules gives rise to life.

A curriculum like that, called Physics First, would reprise the history of the universe, Dr. Lederman said: “Atoms formed molecules, and the molecules formed things that crawled out of the ocean. And here we are, worrying about the whole thing!”

Joseph D. Lykken, a theoretical physicist at Fermilab, said he considered Dr. Lederman “the best ambassador of physics to the general public since Einstein.”

“Instead of intimidating people with fancy jargon and mathematical equations, Leon had the ability to convey the genuine joy and fun of doing science,” Lykken said in an interview. “He used his inexhaustible grab bag of jokes to burst the bubble of the scientist as dignified brainiac and bring modern science back to the human scale.”

Reaching for ways to make physics go down easier, he nicknamed the Higgs boson “the God particle,” to the consternation of some colleagues. That was also the name of his book — a popularization of physics published in 1993 — written with journalist Dick Teresi.

“The publisher wouldn’t let us call it the Goddamn particle,” they wrote, noting how successfully the Higgs was eluding capture in particle accelerator experiments. Its existence was not established until 2012. (The Higgs boson, which interacts with other particles to give them mass, was named after the British theoretical physicist Peter Higgs.)


The source of his humor, Dr. Lederman said in the Times interview, came “from a terror of taking myself seriously.”

Leon Max Lederman was born on July 15, 1922, in Manhattan, where his parents, Morris and Minna (Rosenberg) Lederman, Jewish immigrants from Russia, ran a laundry business. Leon grew up in the Bronx and graduated from James Monroe High School in 1939 and from City College of New York in 1943. His bachelor’s degree was in chemistry, but by then he was already finding himself drawn to physics.

After serving in France during World War II with the Army Signal Corps, he entered the graduate school of physics at Columbia University, where he received his PhD in 1951. He was soon working at the school’s new particle accelerator at the Nevis Laboratories in Irvington, N.Y.

In 1962, his experiment at Brookhaven National Laboratory on Long Island with Schwartz and Steinberger demonstrated the existence of two kinds of neutrinos. One is associated with the electron and another with its heavier cousin, the muon. Later on, physicists found an even heftier version of the electron called the tau, which is accompanied by a tau-neutrino.

These discoveries ultimately helped form the scaffolding for the Standard Model, a crowning achievement of 20th century physics. Everything is made from three families of subatomic particles, each of which also includes a pair of quarks.


It was one of these — the bottom quark — that Dr. Lederman and his Fermilab team discovered in 1977. (Quarks called up, down, strange, and charm had already been confirmed by other scientists, and in 1995 the top quark was found, also at Fermilab.)

After leaving Columbia University, Dr. Lederman became director of Fermilab in 1979. There he oversaw the construction of the Tevatron, the most powerful accelerator of its day, capable of colliding particles at energies up to 1 trillion electron-volts. Probing deeper into the pieces of matter would require even more firepower, and throughout the 1980s Dr. Lederman was an avid promoter of government funding for the Superconducting Super Collider, which would have been the most powerful machine on the planet, to be built in Texas. The dream was dashed when Congress canceled funding in 1993.

In 1993, Dr. Lederman retired from Fermilab to become a professor of physics at the University of Chicago. In 1992 he served as president of the American Association for the Advancement of Science.

He and his wife, Ellen, moved to their place in Idaho, in Driggs, just before his 90th birthday. Found to have dementia, he was advised by his doctors to live in peaceful surroundings.

“I sit on my deck and look at the mountains,” he told the Associated Press in 2015.

Dr. Lederman’s first wife, Florence Gordon Lederman, died in 1990. He married Ellen Carr in 1981. In addition to her, he leaves two daughters, Rena Lederman, a professor of anthropology at Princeton, and Rachel Lederman, a civil rights lawyer; a son, Jess, a writer; and five grandchildren.