His death was confirmed by the Max Planck Institute for Biophysical Research, which Eigen founded in 1971.
Eigen was a young scientist at the University of Göttingen in the early 1950s when, while studying extremely rapid chemical reactions — sometimes faster than a billionth of a second — he decided to figure out a way to time them. He had been inspired, and vexed, by a line in a textbook that described certain chemical reactions as “immeasurably fast.”
“I was then at the age when one accepts practically nothing unquestioned, and so I started to reflect on just how fast an ‘immeasurably fast’ reaction might be,” Eigen recalled in his Nobel lecture.
He realized the best way to calculate the infinitesimal time it took for a reaction to occur was to start with a chemical system in a state of equilibrium and then perturb the system with a quick burst of energy, like high-frequency sound. The chemical system would soon relax back into stability, and he reasoned that scientists could measure details like the reactions’ speed by observing the energy the system absorbed as it returned to equilibrium.
The process was called chemical relaxation, and its development earned Eigen a share of the 1967 Nobel with Ronald G.W. Norrish and George Porter, who devised a technique to set off and study chemical reactions using flashes of light.
Eigen’s research helped chemists gain a much greater understanding of enzymes, biologically critical substances that catalyze specific chemical reactions, among other things.
After Eigen won the prize, he advocated an interdisciplinary approach to scientific inquiry, which he pursued by combining two Max Planck institutes, one devoted to physical chemistry and the other to spectroscopy, to create the Institute for Biophysical Chemistry near the central city of Göttingen, then in West Germany.
The institute’s integration of different specialties and techniques has since become commonplace in the life sciences, and it informed much of Eigen’s later work. In recent decades he focused on the chemical origins of life, studying topics like the perplexing biological nature of viruses, the self-organization of matter and the applicability of Darwinian ideas about evolution to the molecular level. His ideas helped create evolutionary biotechnology, a new branch of the field.
Manfred Eigen was born on May 9, 1927, in Bochum, in western Germany, to Hedwig and Ernst Eigen. His father was a cellist in the Bochum symphony orchestra, and Manfred began studying piano in the hope of becoming a concert pianist.
When his enthusiasm for the piano waned, his father insisted he use the time he would have spent practicing to develop another skill, so Manfred began experimenting in a small, and occasionally explosive, home chemistry laboratory. He took up the piano again before he finished high school.
As a teenager during World War II, he served in the German air force auxiliary in an anti-aircraft unit. After the war he made his way to the University of Göttingen, where he studied chemistry under Werner Heisenberg, a Nobel laureate, and Wolfgang Paul, who became one.
Eigen completed his doctorate when he was 24 and moved to the Max Planck Institute for Physical Chemistry in 1953. He presented his relaxation-measurement method to the Faraday Society, a group of physical chemists, in London the next year.
In 1971 Eigen was named to lead the department of chemical kinetics at the Institute for Biophysical Chemistry. He held that position until he retired in 1995.
Eigen presented his ideas in books like “Laws of the Game: How the Principles of Nature Cover Chance” (1981), which he wrote with a research partner, Ruthild Winkler (later known as Ruthild Winkler-Oswatitsch).
Jeremy Bernstein, an author of books on science, wrote in a review in The New York Times that “Laws of the Game” was “not the kind of reading that many of us like to do.” But he added, “It is a remarkable, fascinating and very profound” book, “a sort of intellectual garden salad to be savored slowly and digested carefully.”
Bernstein also praised the writers’ tone in the book, saying it made them seem as if they “are good friends, and that this book originated in conversations on hikes and ski tours and over bottles of wine.”
In time they became more than friends; they married. Now known as Ruthild Oswatitsch Eigen, she survives him. Eigen’s survivors also include a son, Gerald, and a daughter, Angela Eigen, both from an earlier marriage, to Elfriede Müller.
This article originally appeared in The New York Times.