Stability of general relativistic Miyamoto-Nagai galaxies
نویسندگان
چکیده
The stability of a recently proposed general relativistic model of galaxies is studied in some detail. This model is a general relativistic version of the well known MiyamotoNagai model that represents well a thick galactic disk. The stability of the disk is investigated under a general first order perturbation keeping the spacetime metric frozen (no gravitational radiation is taken into account). We find that the stability is associated with the thickness of the disk. We have that flat galaxies have more not-stable modes than the thick ones i.e., flat galaxies have a tendency to form more complex structures like rings, bars and spiral arms.
منابع مشابه
Relativistic Models of Galaxies
ABSTRACT A special form of the isotropic metric in cylindrical coordinates is used to construct what may be interpreted as the General Relativistic versions of some well known potential-density pairs used in Newtonian gravity to model three-dimensional distributions of matter in galaxies. The components of the energy-momentum tensor are calculated for the first two Miyamoto-Nagai potentials and...
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