Lecture

Stability of Stellar Systems

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In course

PHYS-401: Astrophysics IV : stellar and galactic dynamics

The aim of this course is to acquire the basic knowledge on specific dynamical phenomena related to the origin, equilibrium, and evolution of star clusters, galaxies, and galaxy clusters. ...

Description

This lecture explores the stability of stellar systems at equilibrium, focusing on perturbation theory and linear response theory. Topics include the principle of maximum entropy, linearized equations for self-gravitating systems, and the Jeans instability. The instructor discusses the response of homogeneous fluids and stellar systems to weak perturbations, emphasizing stability conditions and dispersion relations.

Instructor

Yves Revaz

Yves Revaz is a scientist at LASTRO/EPFL. After successful studies in physics at EPFL, he accomplished his PhD entitled: "Dynamics of external regions of spiral galaxies and constraints on the dark matter", at the Geneva Observatory in the galactic dynamics group of Prof. D. Pfenniger. He then moved to the Paris Observatory to work at the LERMA (Laboratory for Studies of Radiation and Matter in Astrophysics) under the supervision of Prof. F. Combes on the understanding of cooling flows in galaxy clusters. He joined LASTRO at EPFL in 2007, where, in collaboration with Pascale Jablonka, he developed a new TreePM/SPH chemo-dynamical code called GEAR, designed to study the chemical evolution of galaxies. His current main research focus on the evolution of dwarf spheroidal galaxies and their link with the cosmology. Yves Revaz is also the author of pNbody, a parallelized python toolbox designed to manipulate large N-body systems.

Official source

Ontological neighbourhood

Physics

Relativity: General relativity

Thermodynamics: Statistical mechanics

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