Donald Lynden-Bell

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Donald Lynden-Bell (born Dover, England April 5, 1935) is a British astrophysicist, best known for his theories that galaxies contain massive black holes at their centre, and that such black holes are the principal source of energy in quasars. Lynden-Bell has been the president of the Royal Astronomical Society. He currently works at the Institute of Astronomy in Cambridge; he was the Institute's first director. Educated at the University of Cambridge, in 1962 he published research with Olin Eggen and Allan Sandage arguing that our galaxy originated through the dynamic collapse of a single large gas cloud. In 1969 he published his theory that quasars are powered by massive black holes accreting material. From counting dead quasars, he deduced that most massive galaxies have black holes at their centres.

He was also a member of a group of astronomers known as the Seven Samurai which postulated the existence of the Great Attractor, a huge, diffuse region of material around 250 million light-years away that results in the observed motion of our local galaxies.

[edit] Chronology

• 53-56: (undergrads) Mach's Principle; Relativity; Quantum mechanics; Statistical mechanics
• 57-60: MHD X type neutral points, Radio astronomy ; Integrals of motion in stellar dynamics & mechanics, separable systems ; Accretion disks, energy principle in axial symmetry; Spiral structure, galaxies
• 1960s: Formation of the Galaxy, its chemical evolution (ELS); Violent relaxation, negative specific heat, gravothermal catastrophe; Io and radio emission of Jupiter; Black holes in Galactic Nuclei; Magnetic accretion disks; Quasars.
• 1970s: Quasar luminosity and density function, the C- method in statistics; Accretion disks around TTauri stars; Relativistic self gravitating Mestel disks; self similar evolution of globular cluster core collapse
• 1980s: Energy principles in fluid mechanics; Isocirculational systems and Kelvin's theorem; Magellanic Stream and local group dynamics; Dark matter: large scale streaming motions and the galaxy distribution
• 1990s: Dipole in extragalactic light; Relativistic exact solutions; Mach's principle in general relativity; Newtonian mechanics without absolute space; Exact self similar solution in MHD; Negative specific heat in astronomy physics and chemistry; Exact N body solution in classical and Quantum mechanics; Ghosty streams in the Milky Way
• 2000s: Separability of motion in electromagnetic fields; Exact optics without coma or spherical aberration; The relativistic rotating charged disk and sphere; MHD jets from accretion disks

His current research mainly focuses on astrophysical jets and general relativity.

[edit] Honors

Awards

• Eddington Medal (1984)
• Gold Medal of the Royal Astronomical Society (1993)
• Dirk Brouwer Award of the American Astronomical Society, Division for Dynamical Astronomy (1991)
• Karl Schwarzschild Medal (1983)
• National Academy of Sciences, John J. Carty Award for the Advancement of Science (2000)
• Bruce Medal (1998)
• Henry Norris Russell Lectureship (2000)

Named after him

• Asteroid 18235 Lynden-Bell