Is Dark Matter Needed in Galaxies?
Arguments indicating that galaxies and galaxy clusters should be considered open, forming systems are presented. Galaxies interact with the intergalactic medium, and are not in virial equilibrium (determined by gravitation and rotation). The usual interpretation of the rotation curves of the outer regions of galaxies beyond the visible stellar disk—that they imply the presence of a massive dark-matter halo— could be erroneous in this case: if the intergalactic medium is being accreted in these regions, the orbital speeds of clouds of neutral hydrogen will not be determined purely by the gravitation of the mass inside their orbits. Galaxy clusters accrete matter (intergalactic gas and galaxies) from the filaments of the large-scale structure at whose intersections they are located. Only their inner regions can approach virial equilibrium. Therefore, the high speeds of galaxies and the high temperature of the intergalactic gas in clusters does not necessarily imply the presence of a high mass of dark matter in galaxy clusters.
Unable to display preview. Download preview PDF.
- 8.I. K. Rozgacheva, in Abstracts of Award Winning and Honorable Mention Essay for 1989 (Gravity Research Foundation, Wellesley Hills, MA, 1989), Abstract No. 25.Google Scholar
- 9.I. K. Rozgacheva, in Proceedings of the 5th Marcel Grossmann Meeting on Recent Developments in Theoretical and Experimental General Relativity, Gravitation and Relativistic Field Theories, Ed. by D. G. Blair and M. J. Buckingham (1989), p. 1113.Google Scholar
- 11.S. Raghunathan, F. Bianchini, and C. L. Reichardt, arXiv:1710. 09770 [astro-ph. CO] (2017).Google Scholar
- 15.M. A. Lara-López, J. Cepa, A. Bongiovanni, A. M. Pérez García, et al., Astron. Astrophys. 521, L53 (2010).Google Scholar
- 34.L. D. Landau and E. M. Lifshitz, Course of Theoretical Physics, Vol. 2: The Classical Theory of Fields (Nauka, Moscow, 1988; Pergamon, Oxford, 1975).Google Scholar