Alar Toomre
Alar Toomre ( born February 5, 1937 in Rakvere ) is a native of Estonia astronomer and mathematician who immigrated to the United States in 1949. He is a professor of applied mathematics at the Massachusetts Institute of Technology. He conducts research especially in the field of the dynamics of galaxies.
Life
Toomre comes from Estonia and emigrated in 1949 from Germany to the United States. He studied aeronautical engineering and physics at MIT. He gained a topic in fluid dynamics at the University of Manchester in England, where he studied with a Marshall Scholarship doctoral degrees. He then went to MIT for two years in the Mathematics Department. After a year at Princeton University, he returned to MIT, where he was Associate Professor of Mathematics in 1965.
Work
Toomre important theoretical contribution to the dynamics of galaxies. In 1964 he developed the Toomre criterion that describes the conditions under which a differentially rotating disk of stars in a galaxy is stable.
In 1972 he published with his brother Yuri a job in the building was shown on previous work of other astronomers first comprehensive how can form by tidal effects long arms or bridges in the interaction of two galaxies. Thus, the appearance of interacting galaxies systems like the Antennae galaxies has been explained. Because of the limited computing power at that time he simulated relatively few stars and modeled their movement to simplified assumptions referred to in the restricted three-body problem under the influence of the core areas of the galaxies, to explain the formation of tidal tails but this is sufficient.
In 1977, he suggested that elliptical galaxies form by mergers of spiral galaxies, and that the current abundance of elliptical galaxies and the present fusion frequency of spiral galaxies fit to ensure that all elliptical galaxies may have originated in this way about the age of the universe of time. While this estimate is now considered too simplistic description of the course of galaxy evolution, the development of merging spiral galaxies to elliptical galaxies is accepted. Toomre illustrated his ideas with the Toomre sequence, which contains samples of galaxies at various stages of the merger process.
Publications (selection)
- Alar Toomre: On the gravitational stability of a disk of stars. In: Astrophysical Journal. Volume 139, 1964, p 1217
- Alar Toomre and J. Toomre: Galactic bridges and tails. In: Astrophysical Journal. Volume 178, 1972, p 623
- Alar Toomre: Mergers and some Consequences. In: BM Tinsley and RB Larson ( eds.): The Evolution of Galaxies and Stellar Populations. Yale University Press, New Haven 1977, p 401