## Title data

Hadžić, Mahir ; Rein, Gerhard ; Straub, Christopher:

**On the Existence of Linearly Oscillating Galaxies.**

*In:* Archive for Rational Mechanics and Analysis.
Vol. 243
(2022)
.
- pp. 611-696.

ISSN 1432-0673

DOI: https://doi.org/10.1007/s00205-021-01734-4

## Abstract in another language

We consider two classes of steady states of the three-dimensional, gravitational

Vlasov-Poisson system: the spherically symmetric Antonov-stable steady states

(including the polytropes and the King model) and their plane symmetric analogues. We completely describe the essential spectrum of the self-adjoint operator

governing the linearized dynamics in the neighborhood of these steady states. We also show that for the steady states under consideration, there exists a gap in the

spectrum. We then use a version of the Birman-Schwinger principle first used by

Mathur to derive a general criterion for the existence of an eigenvalue inside the first gap of the essential spectrum, which corresponds to linear oscillations about the

steady state. It follows in particular that no linear Landau damping can occur in the

neighborhood of steady states satisfying our criterion. Verification of this criterion requires a good understanding of the so-called period function associated with each

steady state. In the plane symmetric case we verify the criterion rigorously, while

in the spherically symmetric case we do so under a natural monotonicity assumption for the associated period function. Our results explain the pulsating behavior

triggered by perturbing such steady states, which has been observed numerically.

## Further data

Item Type: | Article in a journal |
---|---|

Refereed: | Yes |

Institutions of the University: | Faculties > Faculty of Mathematics, Physics und Computer Science Faculties > Faculty of Mathematics, Physics und Computer Science > Department of Mathematics Faculties > Faculty of Mathematics, Physics und Computer Science > Department of Mathematics > Professorship Applied Mathematics Faculties > Faculty of Mathematics, Physics und Computer Science > Department of Mathematics > Professorship Applied Mathematics > Professor Applied Mathematics - Univ.-Prof. Dr. Gerhard Rein Profile Fields > Advanced Fields > Nonlinear Dynamics Faculties Profile Fields Profile Fields > Advanced Fields |

Result of work at the UBT: | Yes |

DDC Subjects: | 500 Science > 510 Mathematics |

Date Deposited: | 10 Jan 2022 08:18 |

Last Modified: | 24 Jun 2022 09:55 |

URI: | https://eref.uni-bayreuth.de/id/eprint/68247 |