Unstable Galaxy Models
Astrophysics of Galaxies
2013-03-13 v1
Abstract
The dynamics of collisionless galaxy can be described by the Vlasov-Poisson system. By the Jean's theorem, all the spherically symmetric steady galaxy models are given by a distribution of {\Phi}(E,L), where E is the particle energy and L the angular momentum. In a celebrated Doremus-Feix-Baumann Theorem, the galaxy model {\Phi}(E,L) is stable if the distribution {\Phi} is monotonically decreasing with respect to the particle energy E. On the other hand, the stability of {\Phi}(E,L) remains largely open otherwise. Based on a recent abstract instability criterion of Guo-Lin, we constuct examples of unstable galaxy models of f(E,L) and f(E) in which f fails to be monotone in E.
Cite
@article{arxiv.1303.2988,
title = {Unstable Galaxy Models},
author = {Zhiyu Wang and Yan Guo and Zhiwu Lin and Pingwen Zhang},
journal= {arXiv preprint arXiv:1303.2988},
year = {2013}
}