A classical flow instability and its connection to gaseous galactic disk hydrodynamics

Georgios H. Vatistas

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A classical flow instability and its connection to gaseous galactic disk hydrodynamics

Georgios H. Vatistas

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Abstract

Water vortices are known to develop polygon structures inside their cores. The apexes of the polygonal manifestations are the result of satellite vortices attached to the parent vortex. Exploiting the analogy between the shallow water hydraulics and the two-dimensional compressible gas flows we arrive to the following line of reasoning concerning the spiral galactic structure. The backward free surface fore ripples of the advancing pressure disturbance in the hydraulic system should appear as high-density spirals in the gaseous galactic disk. Since the number of galactic arms is equal to the number of satellite eddies in the parent vortex, spiral galaxies with say two arms will possess two nuclei. The last appears to be in complete agreement with the latest observations regarding M 31 and Mrk 315 galaxies. If the present hypothesis is accurate then a closer look at the central regions of multi-tentacle spiral galaxies should also reveal that these have multiple nuclei.

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Georgios H. Vatistas. 2007-01-02. A classical flow instability and its connection to gaseous galactic disk hydrodynamics. https://arxiv.org/abs/astro-ph/0701036

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