On the Minimum Energy Configuration of a Rotating Barotropic Fluid
Astrophysics
2007-05-23 v1
Abstract
In a recent paper (astro-ph/0207561, posted on July 25, 2002), Fromang & Balbus state that ``a uniformly rotating barotropic fluid in an external potential attains a true energy minimum if and only if the rotation profile is everywhere subsonic. If regions of supersonic rotation are present, fluid variations exist that could take the system to states of lower energy.'' We present a simple counter-example which demonstrates that the stablity criterion presented by Fromang & Balbus is incorrect.
Cite
@article{arxiv.astro-ph/0208161,
title = {On the Minimum Energy Configuration of a Rotating Barotropic Fluid},
author = {Ramesh Narayan and James E. Pringle},
journal= {arXiv preprint arXiv:astro-ph/0208161},
year = {2007}
}
Comments
4 pages; not submitted to any journal