Obituary of Edward R. (Ted) Harrison

Cosmologist Edward R. (Ted) Harrison, emeritus Distinguished University Professor of Physics and Astronomy at the University of Massachusetts Amherst, died on 29 January 2007 in his retirement city of Tucson, Arizona, where he was adjunct professor at the Steward Observatory, University of Arizona. Perhaps best known for his work on the growth of fluctuations in the expanding universe and his books on cosmology for the dedicated layperson, Ted had extremely broad interests, and he published more than 200 papers in space sciences, plasma physics, high energy physics, physical chemistry, and, principally, many aspects of astrophysics. He was a Fellow of the American Physical Society, the American Association for the Advancement of Science, the Royal Astronomical Society, and the Institute of Physics (UK).

Ted Harrison was born 8 January 1919 in London, England. His education at Sir John Cass College at London University was interrupted by the Second World War, during which he served for 6 years with the British Army in various campaigns, ultimately acting as Radar Adviser to the Northern Area of the Egyptian Army.

Following the War Ted became a British Civil Servant, at first with the Atomic Energy Research Establishment in Harwell and then at the Rutherford High Energy Laboratory. During this period he acquired the equivalent of university degrees, becoming a graduate, then an Associate, and finally a Fellow of the Institute of Physics. His somewhat unorthodox education may have contributed to his broad interests and his very intuitive and physical approach to scientific problems. The latter became the bane of generations of graduate students, who might find themselves asked on their physics qualifying exams to calculate the length of a wild goose chase (how far do YOU think a goose can fly on a meal?) or the inductance of a wedding ring .

Ted came to the US in 1965 as a NAS-NRC Senior Research Associate at NASA’s Goddard Space Flight Center. In 1966 he became one of the three founders of the Astronomy Program within the Department of Physics and Astronomy at the University of Massachusetts. Over the next 30 years he was also instrumental in the revival of the Five College Astronomy Department, which links the University to Amherst, Hampshire, Smith and Mount Holyoke Colleges, and he played a key role in the growth of the corresponding astronomy graduate program to international recognition.

Ted’s research in cosmology included a series of papers discussing the physics of the early universe and the evolution of galaxies from primordial fluctuations, His work led to what came to be called the Harrison-Zeldovich spectrum for density fluctuations. But Ted turned his hand to any physical problem that caught his interest, from thermonuclear power, to the origin of galactic magnetic fields, to the acceleration of pulsars, to the diffusion of dust in molecular clouds. He even managed to combine cosmology and astrobiology, suggesting that if there exist a multitude of universes, those like our own with intelligent life may be the result of natural selection.

Ted was a wonderful writer, whose books frequently illustrate points of physics or cosmology with references to poetry or to classical history and philosophy. He was fascinated with Olber’s Paradox, the question of why the sky is dark at night if the universe is filled with bright stars and galaxies. His book, Darkness at Night, points out that this is not primarily because the universe is expanding, but rather because the stars and galaxies have had only about 15 billion years to radiate and do not have enough energy to keep radiating for much longer. He points out that this conclusion was anticipated in the writings of Edgar Allan Poe! Again typical of his command of the history of science, Ted’s monograph, Cosmology: The Science of the Universe describes the problem of the cosmic edge of the universe by quoting fifth century BCE soldier-philosopher Archytas, who asked what happens to a spear that is hurled across the outer boundary of the universe?

But to many of us, Ted’s most intriguing book is Masks of the Universe (second edition published just 3 years ago). Is our present cosmology, with ordinary matter, dark matter, and dark energy, but another mask obscuring a Universe which will remain perforce forever unknown? Will the LCDM model be looked upon some day in the same way that we now view the medieval, the geometric, or the mythic universes of earlier eras? Read the book and form your own opinion!