Ralph Asher Alpher, noted cosmologist, physicist, and educator, died on August 12, 2007, in Austin, Texas. Alpher developed the first model for primordial nucleosynthesis in the hot early Universe and, with Robert Herman, first predicted the cosmic microwave background radiation. During his long and productive career, he published over one-hundred papers, a book translation, chapters in a number of books (primarily in cosmology), and The Genesis of the Big Bang, a book about his life in cosmology, co-authored with Robert Herman. Ralph's work has been cited by the American Physical Society News as one of the Top Ten Astronomical Triumphs of the Millennium.Born in Washington, D.C., on February 3, 1921, Ralph was the youngest of four children of building contractor Samuel and Rose Maleson Alpher, immigrants from Russia and Latvia. He attended Roosevelt High School in Washington, graduating at the age of sixteen. A scholarship was offered by the Massachusetts Institute of Technology, but then suddenly withdrawn after a meeting with an alumnus. (Ralph would wonder all his life whether the withdrawal was due to his Jewish background.) Instead, he attended evening classes at George Washington University while working full time, earning his B.S. in 1943, his M.S. in 1945, and his Ph.D. in 1948. Ralph's master's thesis on the sources of energy in stars was completed with mentor George Gamow. Gamow then accepted him to work on a Ph.D. dissertation on the formation of galaxies, studying the growth of condensations in a relativistic homogeneous and isotropic expanding medium. Ralph found that such condensations would not grow, but before he finished writing, E. M. Lifshitz independently published similar results in 1946. Ralph started anew, this time modeling the buildup of elements by neutron capture in the hot, early phase of the Universe. Despite the approximations necessary in the pre-computer age, he found consistency with observed abundances of hydrogen and helium. The results were published in the famous Alpher-Bethe-Gamow paper in the Physical Review of April 1, 1948. Gamow, known for his sense of humor, added Bethe's name to the paper, resulting in the abbreviation αβγ. The physics-based approach to a non-static cosmological model of the Universe was viewed with excitement and over three-hundred people attended Ralph's dissertation defense. The story was picked up by the press, with the Washington Post headlining that the "World Began in 5 Minutes, New Theory" based on Ralph's answer to a question about how long primordial nucleosynthesis would have taken. At the same time that he was working on his revolutionary cosmological results, Ralph was hard at work during the day at the Department of Terrestrial Magnetism (1938-1940), the Naval Ordnance Laboratory (1940-1944), and the Johns Hopkins Applied Physics Laboratory (1944-1955). As a physicist contracted to the Navy, he made significant contributions to the development of technology to protect ships against magnetic mines and to magnetically detect submarines from the air. At the Applied Physics Laboratory, he developed a magnetic gradiometer proximity exploder for air-launched torpedoes and worked in programs to develop ground-launched antiaircraft guided missiles. After the war, he worked on supersonic gas dynamics and later cosmic radiation in a group headed by James A. Van Allen. In 1945, Ralph received the Naval Ordnance Development Award in recognition of his work. It was at the Applied Physics Laboratory in 1944 that Alpher met his longtime collaborator and friend Robert Herman, a specialist in molecular spectroscopy, with whom he would collaborate until Herman's death in 1997. Together Alpher and Herman reevaluated the nucleosynthesis calculations and further probed the physics of an early, hot Universe, publishing numerous papers between 1948-1955. The final paper, published in 1953 with James Follin, Jr., established the methodology used for dealing with physical conditions in the early Universe prior to nucleosynthesis. Early on, Alpher and Herman realized that if the expanding Universe began in a hot phase, relic radiation from the era when radiation and matter decoupled should fill the Universe. They published this result in Nature in 1948, predicting that the current temperature should be 5K. In talk after talk, and in a series of papers, they publicized their work and urged observers to start looking for this radiation, but without result. At the time, the model of the hot, expanding Universe, scornfully christened "Big Bang" by Fred Hoyle in 1950, was far from accepted by the cosmology community, especially since the measured value of the Hubble constant produced a very small evolutionary age. Even if the Big Bang model was correct, the consensus was that the relic radiation would be much too faint to detect. Dismayed by the lack of interest in their results, both Alpher and Herman decided in 1955 to give up academia, turning down positions offered at the University of Iowa with James van Allen, and instead accepting jobs at General Electric (GE) and General Motors. Both had families by that time. Ralph had met his wife, Louise Ellen Simons, in 1940. They married January 28, 1942, and had two children, Harriet and Victor. Ralph worked for 32 years at GE Research and Development Center in Niskayuna, New York, on a variety of projects including high-speed aerodynamics, theoretical problems involving the physics of television projection systems, magnetohydrodynamic methods, and, eventually, strategic planning and technology forecasting. The papers about the relic radiation languished in the literature, but Alpher and Herman kept up with developments in cosmology. One can imagine their excitement and gratification when they learned of the serendipitous detection of the cosmic microwave background by Arno Penzias and Robert Wilson in 1965 and found that their model temperature (with updated values of cosmological parameters) was in agreement with the 3K measurement. Their excitement soon turned to dismay as a flurry of resulting publications, most notably those of Robert Dicke, P. James Peebles, and collaborators at Princeton, reproduced their results but neglected to mention Alpher & Herman (1948). For much of the rest of their lives they waited for proper recognition of their prediction. The Nobel Prize of 1978 went to Penzias and Wilson, but Penzias cited Alpher and Herman in his acceptance speech. Gradually recognition came, although Gamow was often credited equally with Alpher and Herman, even though Gamow had not participated in the original calculations and had published independent calculations later shown to be incorrect. Ralph retired from GE in 1987. He taught from 1986 to 2004 at Union College as distinguished research professor, retiring in 2004. Students and faculty remember him fondly for his contributions to Union and his kind nature. Ralph was a member of the board of directors of Dudley Observatory and was its Administrator from 1987 to 2000. He was generous in donating his time to the community, serving on the board of the local public television station WMHT-- including a two-year term as its president--and as mentor to the Boy Scouts. (He was an Eagle Scout himself at age twelve). Among the awards Ralph earned are the Magellanic Premium of the American Philosophical Society, the George Vanderlinden Prize of the Belgium Royal Academy of Sciences Letters and Fine Arts, the George Wetherill Medal of the Franklin Institute, and the Mathematics Prize of the New York Academy of Sciences. In 1993, Alpher and Herman were awarded the Henry Draper Medal of the National Academy of Sciences for their early work on the Big Bang model, nucleosynthesis, and the prediction of the cosmic microwave background radiation. Steven Weinberg wrote in his 1993 book, The First Three Minutes, that Alpher carried out "the first thoroughly modern analysis of the early history of the Universe." Most recently, Ralph was awarded the 2005 National Medal of Science "for his unprecedented work in the areas of nucleosynthesis, for the prediction that universe expansion leaves behind background radiation, and for providing the model for the Big Bang theory."
Bulletin of the American Astronomical Society
- Pub Date:
- December 2007