Global Continuation of a Vlasov Model of Rotating Galaxies

Walter A. Strauss; Yilun Wu

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arXiv · 2203.01454

Global Continuation of a Vlasov Model of Rotating Galaxies

Walter A. Strauss·Yilun Wu

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Abstract

A typical galaxy consists of a huge number of stars attracted to each other by gravity. For instance, the Milky Way has about $10^{11}$ stars. Thus it is typically modeled by the Vlasov-Poisson system. We prove an existence theorem for axisymmetric steady states of galaxies that may rotate rapidly. Such states are given in terms of a fairly general function $\phi$ of the particle energy and angular momentum. The set $\mathcal K$ of such states form a connected set in an appropriate function space. Along the set $\mathcal K$, we prove under some conditions that either (a) the supports of the galaxies become unbounded or (b) both the rotation speeds and the densities somewhere within the galaxy become unbounded.

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Walter A. Strauss, Yilun Wu. 2022-03-02. Global Continuation of a Vlasov Model of Rotating Galaxies. https://arxiv.org/abs/2203.01454

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