Albert G. Petschek died suddenly 8 July 2004. He enjoyed good health and was very active professionally and personally until his death. He was highly respected, particularly in theoretical physics, for his deep, broad-ranging analytical powers, which resulted in contributions to nuclear physics, astrophysics, atmospheric physics, quantum mechanics, and quantum computing.
Albert was born in Prague, Czechoslovakia in 1928. His extended family left Czechoslovakia when its sovereignty was threatened by Germany in 1938 and settled throughout the Western Hemisphere. Albert's father, a banker, settled in Scarsdale, near New York City. Albert graduated from White Plains High School and obtained his BS from MIT in a program accelerated during World War II. While getting his masters degree at the University of Michigan, Albert met his wife, Marilyn, also a physics masters student. In 1953, Albert obtained his PhD from the University of Rochester working with Robert Marshak on aspects of nuclear theory, and joined Los Alamos National Laboratory (LANL), then Los Alamos Scientific Laboratory. Soon thereafter, Albert's younger brother, Harry, also became a PhD physicist. Harry is now well known in plasma physics for reconnection theory.
At Los Alamos, Albert worked closely with Carson Mark, Marshall Rosenbluth, and Conrad Longmire designing the first thermonuclear weapons. His derivation of several radiation diffusion solutions, later published as LAMS 2421, remains a classic in its field, as does work on nuclear theory done with Baird Brandow and Hans Bethe during a sabbatical at Cornell in 1961. Bethe was a frequent visitor to Los Alamos and a close friend. A devoted family man, Albert also valued Los Alamos as a safe, stimulating environment for raising an active family. Like many of the scientists at Los Alamos, Albert enjoyed its ready access to outdoor activities such as hiking and skiing. Albert often combined his passions for intellectual activity and the outdoors - discussing Lie groups around a camp fire or the controversies concerning the origin of lightning in electrical storms while hiking through a high mountain pass, watching a thundercloud form. Albert's son Rolfe was inspired in part by such outings to become a professional physicist.
For more than a decade following his PhD, Albert's primary scientific work was secret, contributing to the security of his adopted country, and he published little in the open literature. However, by the time of his death, Albert's broad interests and scientific rigor had resulted in 69 cited papers on such diverse topics as nuclear theory, plasma physics, radiation, numerical hydrodynamics and plastic flow, astrophysics (supernovae, quasars, gamma-ray bursts), chemical kinetics, atmospheric physics (plumes, electrification), geotectonics, nuclear weapons effects, inertial fusion and quantum computing. Even this list understates Albert's intellectual breadth: while his scientific publications are all in physics, he was also very knowledgeable in some aspects of biology and finance, and his broad-ranging analytical powers were appreciated by practitioners of many professions. In an increasingly specialized world, Albert's broad interests, wide knowledge, and willingness to think deeply about many problems are inspiring.
In 1966 Albert joined the faculty of New Mexico Institute of Mining and Technology (New Mexico Tech) in Socorro, New Mexico, as a full professor. In 1968 he left Tech to spend three years at Science, Systems and Software, a scientific consulting firm in San Diego California, and then returned to New Mexico Tech. Albert's intellectual leadership, the courses he taught in theoretical physics, and his frequent, insightful questions at seminars will long be remembered by those with whom he interacted at New Mexico Tech. Of his 69 published works, 39 were published in collaboration with Stirling Colgate. Colgate, at that time New Mexico Tech's president, had helped recruit Albert there. Albert's PhD students at New Mexico Tech keenly remember his patience, kindness and availability. His office door was always open, and he was eager to lead them through difficulties in their research.
Albert maintained his connection to LANL while at New Mexico Tech, consulting at LANL during many holidays and summers. In 1981 he became one of the first Fellows of Los Alamos National Laboratories. Albert also enjoyed service to the science community, editing a book on supernovae (1990), routinely judging local and regional science fairs, and advising LANL on the recipients of the Los Alamos prize. In 1987, Albert retired from New Mexico Tech and returned full time to Los Alamos in the Physics division. Although he subsequently retired from LANL in 1994, he remained very active at LANL until his death, spending three to four days there most weeks as an emeritus fellow, consultant, and frequent attendee of, and questioner at, seminars and colloquia. During this period his published scientific contributions were primarily to quantum computing and numerical hydrodynamics.
While he was retired Albert's part time status allowed him to spend yet more time with his family and he explored many parts of the world with them. Albert was an avid hiker, cross country skier, mushroom gatherer, gardener, and bicyclist. He commuted by bicycle between his home in La Senda and the Lab, an elevation change of 200 meters, in almost any weather, until his death. He is survived by Marilyn, his wife of 55 years, his brother Harry, his four children, Evelyn, Rolfe, Elaine, and Mark and three grandchildren.