Seminars
Our seminars take place in the lecture room of the building at
Praha–Sporilov.
Next seminar:
13.12.2016 14:00
Jean-Marck Hure
University of Bordeaux, The Laboratory of Astrophysics, CNRS, France
Methods for gravity: from soft to hyper-potentials
Abstract
Jean-Marck Hure
Methods for gravity: from soft to hyper-potentials
Gravitation plays a key-role in structuring most structures in the Universe (stars, planets, galaxies, etc). Unfortunately, the computation of the Newtonian potential and forces, needed in many simulations, remains tricky inside matter and challenging (both numerically and analytically). We will first remind a few basic properties of the gravitational potential, and discuss current point mass singularity-avoidance methods, including gravity ``softening''. We will then discuss the possibility of deriving optimal (i.e. better Newtonian-preserving) prescriptions for the softening parameter. A possible alternative to common techniques (multipole expansions, softening, etc.) is the use of hyper-potentials, which will be outlined in brief.
Previous seminar:
22.11.2016 14:00
Jason Dexter
Max Planck Institute for Extraterrestrial Physics, Garching, Germany
Resolving the event horizon of the black hole in the Galactic Center
Abstract
Jason Dexter
Resolving the event horizon of the black hole in the Galactic Center
Interferometric sub-mm and infrared observations of the Galactic center black hole, Sgr A*, are now resolving angular scales comparable to the expected size of its event horizon. I will discuss how these observations could probe strong field general relativity, focusing especially on the expected appearance of the black hole shadow in emission models of Sgr A*.
If you would like to give a seminar in our group, please contact Vladimir Karas.
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