Dennis William Sciama

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Dennis Sciama
Dennis William Siahou Sciama (1926-1999)
Dennis William Siahou Sciama (1926-1999)
Born November 18, 1926(1926-11-18)
Cairo, Egypt
Died December 18, 1999 (aged 73)
Oxford, UK
Residence UK, Italy
Nationality British
Fields Physicist
Institutions University of Oxford
University of Cambridge
Cornell
Harvard
King's College London
University of Texas at Austin
Scuola Internazionale Superiore di Studi Avanzati
Alma mater University of Cambridge
Doctoral advisor Paul Dirac
Doctoral students John D. Barrow
Adrian Melott
George Ellis
Gary Gibbons
Stephen Hawking
Martin Rees
David Deutsch
Brandon Carter
Known for Astrophysics and cosmology
Religious stance Jewish

Dennis William Siahou Sciama FRS (November 18, 1926–December 18, 1999) was a British physicist who, through his own work and that of his students, played a major role in developing British physics after the Second World War.

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[edit] Life

Sciama earned his Ph.D. in 1953 at Cambridge University under the supervision of Paul Dirac, with a dissertation on Mach's principle and inertia. His work later influenced the formulation of scalar-tensor theories of gravity.

He taught at Cornell, King's College London, Harvard and the University of Texas at Austin, but spent most of his career at Cambridge (1950s and 60s) and the University of Oxford (1970s and early 80s). In 1983, he moved from Oxford to Trieste, becoming Professor of Astrophysics at the International School of Advanced Studies (SISSA), and a consultant with the International Centre for Theoretical Physics. During the nineties he divided his time between Trieste (and a residence in nearby Venice) and Oxford, where he was a visiting professor until the end of his life. His main home remained in his house in Park Town, Oxford.

Sciama drew on his broad knowledge of physics to make fruitful connections among many topics in astronomy and astrophysics. He wrote on radio astronomy, X-ray astronomy, quasars, the anisotropies of the cosmic microwave radiation, the interstellar and intergalactic medium, astroparticle physics and the nature of dark matter. Most significant was his work in general relativity, with and without quantum theory, and black holes. He helped revitalize the classical relativistic alternative to general relativity known as Einstein-Cartan gravity.

Early in his career, he supported Fred Hoyle's steady state cosmology, and interacted with Hoyle, Hermann Bondi, and Thomas Gold. When evidence against the steady state theory, e.g., the cosmic microwave radiation, mounted in the 1960s, Sciama abandoned it.

During his retirement, Sciama pursued a theory of dark matter that consists almost entirely of a heavy neutrino, now disfavored.

A number of the leading astrophysicists and cosmologists of our time completed their doctorates under Sciama's supervision, notably:

Sciama also strongly influenced Roger Penrose, who dedicated his The Road to Reality to Sciama's memory. The 1960s group he led in Cambridge (which included Ellis, Hawking, Rees, and Carter), has proved of lasting influence.

Sciama was elected a Fellow of the Royal Society in 1982. He was also an honorary member of the American Academy of Arts and Sciences, the American Philosophical Society and the Academia Lincei of Rome. He served as president of the International Society of General Relativity and Gravitation, 1980-84.

In 1959 he married Lidia Dina, a social anthropologist, who survived him, along with their two daughters.

[edit] Books by Sciama

  • 1959. The Unity of the Universe. London: Faber & Faber.
  • 1969. The Physical Foundations of General Relativity. New York: Doubleday. Science study series. Short (104 pages) and clearly written non-mathematical book on the physical and conceptual foundations of General Relativity. Could be read with profit by physics students before immersing themselves in more technical studies of General Relativity.
  • 1971. Modern Cosmology. Cambridge University Press.
  • 1993. Modern Cosmology and the Dark Matter Problem. Cambridge University Press.

[edit] References

  • The Renaissance of General Relativity and Cosmology, eds. G. F. R. Ellis et al, Cambridge Univ. Press, 1993. (Contains a Sciama Festschrift with Sciama's complete scientific genealogy).
  • G. F. R. Ellis, "Obituary Dennis Sciama (1926–99)," Nature, 403, p. 722, 2000.

[edit] External links

  • Short bio, the source for much of this entry.
  • Dennis Sciama. Mathematics Genealogy Project. American Mathematical Society. Retrieved on August 15, 2005.


Persondata
NAME Sciama, Dennis William
ALTERNATIVE NAMES
SHORT DESCRIPTION British physicist
DATE OF BIRTH November 18, 1926
PLACE OF BIRTH Cairo, Egypt
DATE OF DEATH December 18, 1999
PLACE OF DEATH Oxford, UK