Julian Krolik
University of Maryland, department of Astronomy (Baltimore, Etats-Unis d'Amérique)
Amphithéâtre Henri Mineur, Institut d'Astrophysique de Paris
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| « The Last Gasp: Dynamics of Accretion onto Black Holes » |
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Julian Krolik |
| Accreting black holes in aggregate produce as much as a few tens of percent of all the light in the Universe (excluding the cosmic microwave background). After many years of guesswork about how accretion takes place (onto black holes or any other central object), we now know its fundamental dynamical mechanism: magneto-rotational instability leads to large amplitude MHD turbulence and outward transport of angular momentum (the "Balbus-Hawley mechanism"). With this firm basis in well-understood physics, we can now employ large-scale numerical simulations in full general relativity to study what happens when matter falls onto black holes. These simulations show that decades-old simple models fail in several important respects and reveal a number of ways in which black hole spin can qualitatively alter the accretion process. |
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vendredi 18 juin 2004 - 11:00 Amphithéâtre Henri Mineur, Institut d'Astrophysique de Paris |
| Page web du séminaire / Seminar's webpage |