Energy extraction from accreting black holes

Date

Dec 17, 2019

Time

4:40 PM - 6:10 PM

Speaker

Prof. Dr. Karl Mannheim

Affiliation

Lehrstuhl für Astronomie und Astrophysik Fakultät für Physik und Astronomie Julius-Maximilians-Universität Würzburg

Language

en

Main Topic

Informatik

Description

Interstellar space is crowded with black holes, objects so compact that not even light
can escape from them. Recent detections of gravitational waves from mergers of black
holes or the picture of a shadow imprinted by the supermassive black hole in the giant
elliptical galaxy Messier 87 onto the glow of surrounding gas are celebrated as
breathtaking confirmations of general relativity. Now, the flickering of gamma rays from
remote extragalactic objects adds another window to witness the physical realm of
Einstein’s legacy: Lightning flashes at TeV energies lasting only a few minutes driven by
particle acceleration close the ergosphere of supermassive black holes confirm energy
extraction from the spinning black holes by electrodynamical processes predicted by
Penrose (1969) and by Blandford and Znajek (1977). The association of gamma-ray
flares with high-energy neutrinos indicates that proton acceleration plays a key role,
possibly solving the century-old question about where the highest energy cosmic ray
nuclei in nature originate from.

1983-1989 Physics studies in Heidelberg and Bonn (Dipl.-phys.).
1989-1992 PhD at MPI für Radioastronomie in Bonn 1989-1992 (Dr. rer. nat.),
advisor: Peter Biermann
1992-1993 Postdoc at MPIfR
1993-1999 Akademischer Rat a.Z., Universitäts-Sternwarte Göttingen
1995 ITP UC Santa Barbara, Ludwig-Biermann-Award (Astronomische Gesellschaft)
1997 Habilitation in Physics
1999-2001 Heisenberg Fellow
Since 2001 Chair of Astronomy and Astrophysics, JMU Würzburg

Key research areas: High-energy radiation processes, extragalactic jets, compact objects,
metagalactic background radiation, indirect dark matter detection

Last modified: Jan 24, 2020, 12:08:47 AM