Walter M. Elsasser
|Walter Maurice Elsasser|
Elsasser in 1989
20 March 1904|
Mannheim, German Empire
14 October 1991 (aged 87)|
Baltimore, United States
Complex system biology
National Medal of Science (1987)|
William Bowie Medal (1959)
Arthur L. Day Medal (1979)
Walter Maurice Elsasser (March 20, 1904 – October 14, 1991) was a German-born American physicist considered a "father" of the presently accepted dynamo theory as an explanation of the Earth's magnetism. He proposed that this magnetic field resulted from electric currents induced in the fluid outer core of the Earth. He revealed the history of the Earth's magnetic field through pioneering the study of the magnetic orientation of minerals in rocks.
The Olin Hall at the Johns Hopkins University has a Walter Elsasser Memorial in the lobby.
Elsasser was born in 1904 in Mannheim, Germany. Before he became known for his geodynamo theory, while in Göttingen in the 1920s, he had suggested the experiment to test the wave aspect of electrons. This suggestion of Elsasser was later communicated by his senior colleague from Göttingen (Nobel Prize recipient Max Born) to physicists in England. This explained the results of the Davisson-Germer and Thomson experiments later awarded with the Nobel Prize in Physics. In 1935, while working in Paris, Elsasser calculated the binding energies of protons and neutrons in heavy radioactive nuclei. Wigner, Jensen and Goeppert-Mayer received the Nobel in 1963 for work developing out of Elsasser's initial formulation. Elsasser therefore came quite close to a Nobel prize on two occasions.
Over 1946–47, Elsasser published papers describing the first mathematical model for the origin of the Earth's magnetic field. He conjectured that it could be a self-sustaining dynamo, powered by convection in the liquid outer core, and outlined a feedback mechanism between flows having two different geometries, toroidal and poloidal (indeed, coining the terms). This had been developed from around 1941 onwards, partly in his spare time during his scientific war service with the U.S. Army Signal Corps.
In his later years, Elsasser became interested in what is now called systems biology and contributed a series of articles to Journal of Theoretical Biology. The final version of his thoughts on this subject can be found in his book Reflections on a Theory of Organisms, published in 1987 and again posthumously with a new foreword by Harry Rubin in 1998.
Some, but not all, of Elsasser's theoretical biology work is still quite controversial, and in fact may disagree with several of the basic tenets of current systems biology that he may have helped to develop. Central to Elsasser's biological thought is the notion of the astronomical complexity of the cell. Elsasser deduced from this that any investigation of a causative chain of events in a biological system will reach a "terminal point", where the number of possible inputs into the chain will overwhelm the capacity of the scientist to make predictions, even with the most powerful computers. This might seem like a counsel of despair, but in fact Elsasser was not calling for the abandonment of biology as a worthwhile research arena, but rather for a different kind of biology where molecular causal chains are no longer the main focus of study. Correlation between supra-molecular events would become the main data source. Moreover, the heterogeneity of logical classes encompassed by all biological organisms without exception is an important part of Elsasser's legacy to both Complex systems biology and Relational Biology.
- The Physical Foundation of Biology. An Analytical Study, (1958), Pergamon Press, London
- Atom and Organism. A New Approach to Theoretical Biology, (1966) Princeton University Press
- The Chief Abstractions of Biology, (1975), North Holland, Amsterdam.
- Memoirs of a Physicist in the Atomic Age, (1978)
- The role of individuality in biological theory, (1970) in Towards a Theoretical Biology vol.3 Edinburgh University Press
- Reflections on a Theory of Organisms. Holism in Biology, (1998) Johns Hopkins University Press (JHU).
Elsasser was elected to the National Academy of Sciences in 1957. From the American Geophysical Union he received the William Bowie Medal, its highest honor, in 1959; and the John Adam Fleming Medal (for contributions to geomagnetism) in 1971. He received the Penrose Medal from the Geological Society of America in 1979 and the Gauss Medal from Germany in 1977. In 1987, he was awarded the National Medal of Science "for his fundamental and lasting contributions to physics, meteorology, and geophysics in establishing quantum mechanics, atmospheric radiation transfer, planetary magnetism and plate tectonics.".
- March 20 - Today in Science History - Scientists born on March 20th, died, and events
- Beyler, Richard H.; Gatherer, Derek (2008). "Elsasser, Walter Maurice". Complete Dictionary of Scientific Biography. 20. Charles Scribner's Sons. pp. 378–381.
- Elsasser, WM (1983). "Biological application of the statistical concepts used in the Second Law". Journal of Theoretical Biology. 105 (1): 103–16. doi:10.1016/0022-5193(83)90427-7. PMID 6656269.
- Elsasser, WM (1982). "The other side of molecular biology". Journal of Theoretical Biology. 96 (1): 67–76. doi:10.1016/0022-5193(82)90156-4. PMID 7109657.
- Elsasser, WM (1981). "Principles of a new biological theory: a summary". Journal of Theoretical Biology. 89 (1): 131–50. doi:10.1016/0022-5193(81)90182-X. PMID 7278305.
- Elsasser, WM (1972). "A model of biological indeterminacy". Journal of Theoretical Biology. 36 (3): 627–33. doi:10.1016/0022-5193(72)90013-6. PMID 5080452.
- Elsasser, WM (1969). "The mathematical expression of generalized complementarity". Journal of Theoretical Biology. 25 (2): 276–96. doi:10.1016/S0022-5193(69)80064-0. PMID 5383506.
- Elsasser, WM (1964). "Synopsis of organismic theory". Journal of Theoretical Biology. 7 (1): 53–67. doi:10.1016/0022-5193(64)90040-2. PMID 5875342.
- Elsasser, WM (1963). "Note on evolution in organismic theory". Journal of Theoretical Biology. 4 (2): 166–74. doi:10.1016/0022-5193(63)90025-0. PMID 5875158.
- Pais, A. (1967). "Symmetries and Reflections. Scientific Essays. Eugene P. Wigner. Indiana University Press, Bloomington, 1967. 288 pp., illus.". Science. 157 (3791): 911. Bibcode:1967Sci...157..911W. doi:10.1126/science.157.3791.911.
- Baianu, I. C.; Brown, R.; Georgescu, G.; Glazebrook, J. F. (2006). "Complex Non-linear Biodynamics in Categories, Higher Dimensional Algebra and Łukasiewicz–Moisil Topos: Transformations of Neuronal, Genetic and Neoplastic Networks". Axiomathes. 16: 65. doi:10.1007/s10516-005-3973-8.
- Łukasiewicz-Topos Models of Neural Networks, Cell Genome and Interactome Nonlinear Dynamic Models http://en.scientificcommons.org/23394472
- Darwin, Charles; Wallace, Alfred Russel (1858). "On the Tendency of Species to form Varieties; and on the Perpetuation of Varieties and Species by Natural Means of Selection". Journal of the Proceedings of the Linnean Society of London. Zoology 3: 46–50.
- Darwin, Charles (1859). On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life (1st ed.). London: John Murray. ISBN 1-4353-9386-4. Retrieved 2008-10-24.
- Gatherer D: Finite universe of discourse. The systems biology of Walter Elsasser. The Open Biology Journal 2 4-15
- Baianu, I.C. 2006. "Robert Rosen's work and complex systems biology", Axiomathes, Vol. 16: 25-34; ISSN 1122-1151 http://www.springerlink.com/content/n8gw445012267381/
- "1959 William Bowie Medal Winner – Walter M. Elsasser". Medals, Awards & Prizes. American Geophysical Union.
- "1971 John Adam Fleming Medal Winner – Walter M. Elsasser". Medals, Awards & Prizes. American Geophysical Union.
- "Penrose Medalists". Past Award & Medaul Recipients. Geological Society of America. Retrieved 24 October 2011.
- "The President's National Medal of Science: Recipient details – Walter Elsasser". National Science Foundation. 28 May 2009. Retrieved 24 October 2011.
- Rubin, Harry (1995). Walter M. Elsasser: 1904–1991 (pdf). The National Academies Press. Retrieved 6 March 2013.
- Gatherer, D (2008). Finite universe of discourse: The systems biology of Walter Elsasser (1904-1991) (pdf). The Open Biology Journal. 1. pp. 9–20. Retrieved 6 March 2013.
- Beyler R & Gatherer D (2007) Walter Elsasser (biography). In: Dictionary of Scientific Biography, new ed. New York: Charles Scribner's Sons Inc.
- Oral History interview transcript with Walter Elsasser 29 May 1962, American Institute of Physics, Niels Bohr Library and Archives
- Elsasser's photo